PACS Essay Example | Topics and Well Written Essays - 1000 words

PACS - Essay Example A PACS consists of at least one or more image acquisition devices (like Computed Tomography Scanners, Ultrasound Scanners, MRI), communication network, a long term storage device and an image review and/or post processing workstation, in other words PACS is used to run medical digital images. All these components enable following processes: image acquisition, image  communication, image storage, image display and image processing. All these processes act as pathways for PACS to improve the quality of diagnosis, extend the reach of services of an expert radiologist, higher efficiency and cost savings (Reiner and Siegel, 2002, 3). Since healthcare is a safety as well as security intense domain, these parameters cannot be compromised. Hence saving and archiving medical images without loosing quality (or information) has been a compelling need of the users of various users dealing with medical images. This concern of the clinicians have been appropriately addressed by a universal standard pertaining to digital medical imaging, this standard is termed as Digital Imaging and Communications in Medicine (popularly called DICOM). DICOM provides all the tools required for diagnostically correct processing and presentation of medical imaging data (Pianykh). DICOM takes care of data transfer, storage and display protocol that contains sets of standards. DICOM incorporates the following processes: Information Management System  Storage, Query/Retrieve,   Study Component, Query/Retrieve, Results Management, Print Management, Media Exchange. The DICOM Standard takes care of levels of the ISO OSI network model and enables the exchange of information on interchange media. DICOM currently defines an upper layer protocol (ULP) that is used over TCP/IP (independent of the physical network), messages, services, information objects and an association negotiation mechanism. These definitions ensure that any two implementations of a compatible set of services and

Culture and Education Essay Example for Free

Culture and Education Essay The institutions of education which are shaping the minds of todays youth do not all teach the same facts and curriculum. Throughout the world there are differing opinions on what, when, and how certain facts, theories, and concepts should be taught. Not all children are taught the same truths; this statement might sound unfair, or maybe incomprehensible. How, one may ask, could accepted truths not be taught as such; and what decides whether they will be or not? Cultural constructs such as norms, morals, and shared religious beliefs play a role in what education consists of and looks like for different groups of children all over the world. Let’s take a look at the common History class. When taking a History class in the United States you will most likely be learning U. S. History, and even if you take a World History class it will still focus on the U. S. and how it interacted with and impacted other countries. In Japan you would be learning Japanese History. However if you were to read through certain Japanese history text books you might be alarmed to find that Japan is portrayed not only as a victim instead of an aggressor in the context of WWII and that there is a lack of general information regarding their participation in the war all together. Largely in debate is the Nanking Massacre in which the Japanese allegedly systematically kill 300,000 people including both civilians and soldiers. There are two schools of thought, The Massacre Denial and The Massacre Affirmative. Japan’s culture is one of honor which makes it difficult for them to acknowledge their mistakes, and thus largely try to ignore the Nanking incident in a sort of sweep it under the rug fashion. In Japanese Universities many teachers will teach that while the event did happen the numbers were closer to 10,000 and included only soldiers while some classes do not cover the topic at all. In China they teach that it did in fact happen and claim the body count reached 300,000 or more. The effect of this difference in truths being taught is that in Japan younger generations do not view Japan as having been an aggressor in the war, and younger Chinese generations continue to view the Japanese as horrible people. Then there is Human Growth and Development / Sex Ed. While many believe it is a necessary section of what children learn in Health classes, some find it to go against their culture. In certain groups simply discussing opening a woman’s menstrual cycle or how a baby is made can be taboo. Not to mention once you start getting into discussions about birth control options and how to properly put on a condom all hell can break lose. To those whose culture forbids them from having premarital sex, these classes can seem obscene and worrisome in the sense that perhaps these classes will cause their children to commit these sins after acquiring knowledge about it. Then there are also cultures who simply think that school is not a place for these things to be covered, and that it is the parents’ responsibility to teach their children about them themselves. Another main concern is also when these things will be taught. I myself remember being taught about the changes that would happen to my body once I hit puberty starting around 4th grade in Human Growth and Development classes. It wasnt until high school that anyone really talked about sex, and ways to make it safe. Some people think that due to rates of teen pregnancy and the way these teen parents seem to be getting younger and younger, that it may be necessary to begin bringing up safe sex much earlier on. However, many people believe this would be overstepping many cultural boundaries. Either way schools almost always allow parents to remove children from these classes as they understand that these matters are viewed differently by different cultures. The way in which the Theory of Evolution is taught throughout the U. S. s another prime example of how cultural beliefs try and sometimes succeed in shaping educational curriculum. While throughout the science community the Theory of Evolution is greatly accepted as the reason behind animals and humans being the way they are today, the fashion in which it is taught to students throughout the United States varies from state to state. A map published in a 2002 issue of Scientific American which was based on data collected by Lawrence S. Lerner of California State University the map depicts the quality of coverage given to the Theory of Evolution in each states Science Standards. It shows that while in a little over half of the states the teaching of the theory is considered very good to satisfactory, a number of states, particularly several in the Bible Belt, an area of the Southern United States where the culture reflects the strongly conservative and Evangelical population which boasts higher church attendance than the countries average; there is â€Å"unsatisfactory, useless, or absent† coverage of the theory. The battle to allow for another theory to be taught instead of, or alongside Evolution is ongoing but has been approved in Kentucky as well as Tennessee. These states now teach Creationism/Creation Science, â€Å"A literal belief in the biblical account of Creation as it appears in the Book of Genesis. Creationists believe that the creation of the world and all its creatures took place in six calendar days; they therefore deny the theory of evolution. †() In areas of the U. S. where religion is not a large part of culture it is not likely for Creationism to be seen as something which should be taught in science classes, however is areas where the religious roots of a culture run deep the attempts such as these to control education are apparent. If one were to make a list of all things which are agreed upon by their culture to be truths and compared it to that of another’s there would undoubtedly be differences. While one would hope the majority of facts matched there will always be variations. This is reflected through the words of teachers and the knowledge of their students. Ones’ culture defines what education consists of and looks like for them, perhaps it seems unfair, but it is undeniably true. Not all children are taught the same truths.

Voice over Internet Protocol (VoIP) Technology

Voice over Internet Protocol (VoIP) Technology ABSTRACT: Voice over Internet Protocol (VoIP) technology which attract extra attention and awareness to the world wide business. IP telephonys system will affect the sending voice transmission in the form of packet over the IP network in the VoIP applications. Now a days many industries will use the VoIP technologies to provide the Security. In this project, I provided a variety of VoIP safety intimidation and probable approach to handle the intimidation in VoIP application. VoIP is naturally susceptible to networks attack, like hateful codes (i.e., worms, viruses, Trojans), denial-of-service (DoS), distributed DoS (DDoS), pharming, and (though non malicious) sparkle were crowded. These attacks also spoil grimy system by overriding assets, distracting valid user, compromise private informations, or by demeaning code and records. This break affect the contaminated system, it also destroy the unaffected (or even non-vulnerable) ones. All system associated to the Internet are responsive to hateful code which try to contaminate as much as hosts is probable, cause overcrowding on the network communications. The QoS which is provide to the end user is of highest significance and it is the main issue to implement the VoIP system, since if the exchange is indecipherable then there is no position in giving the service. The major factor which distresses the superiority of services is Latency, Jitter and Packet loss. CHAPTER-1 1.0 Introduction The voice enterprises continuously providing voice conversation services on over broad band by discovering the current market issues and network issues from past 20 years, the voice transition industry undergone various security and network issues to produce better quality voice service to transit on over broad band. The current voice market has been step up into the new level of voice protocols for providing VoIP services during low bandwidth, high level of data and voice transmission provisions. The VOIP technologies allow sharing the resource of WAN for supporting data and voice for saving the cost for transmission process [1]. The VoIP provides many advantages to the enterprises, the migration of voice and telephone application form TDM switch network to IP packet switched network provides many advantages to enterprises during the migration of voice into IP application the enterprises need to provide security to the data applications [2]. However the enterprises need to identify the security issues and employee new techniques to protect against attacks. Security and QoS is a main aspect of VOIP system, the data on voice networks have been attacked by viruses, worms, DOS attacks and other unknown authentication users [3]. The VOIP architecture is a complete network hierarchical structure which is compound with many of the networking devices, the design structure have to ensure that whether the components will cope the unwanted attacks. The protocol structure in a VOIP system is a more sensible factor due to the poor ambitious. Here we introduce the attacks on over VoIP system. VOIP Overview VoIP stands for Voice over Internet Protocol which is the mainly used in the transmission of voice communications through IP network like internet, public switched networks [4]. The concept of VoIP mainly targets of the transmission of voice based messages and applications by using different protocols and is transmitted via the internet. The basic steps involved in the transmission of voice signals through the internet are:  · Conversion of voice to analog and digital signal.  · Compression and conversion of the signal into Internet Protocol Packets to broadcast over Internet. VoIP systems adopt different session control protocols for commanding over the set-up, tear-down of calls and also different audio codecs which allow for encoding the voice signal and allow the transmission. These audio codecs may vary form system to system where some of them are based on the narrow band and some on the compressed speech where some other system may use high fidelity audio codecs. Technologies used to implement VoIP:  · H.323 [12]  · IP Multimedia Subsystem (IMS)  · Session initiation Protocol (SIP) [5]  · Real-time Transport Protocol (RTP) [5] 1.1 Problem Definition In the past days the VoIP security is a not a big concern the people were mainly concerned with the functionalities, cost and the usage, but the VOIP communication trend has been encouraged; the VOIP communication system widely accepted by the people; due to the high acceptance of VOIP system the security issues are main concern. However the VoIP services are rapidly growing in the current voice communication system, many unauthenticated users and hackers are stealing the VoIP services and hacking the services from the service providers and re routing to their personal usage. Some of the security standards are not credential they only supports to authentication over calls, but the problem with the service theft. The security concerns will affect on quality of the system, due to the security tools and security solutions will conflict on quality of service. The system will accept the security tools those tools shouldnt decrease the quality. The basic issue of the quality is firewall. The firewall will blocks the calls for security constrains it will not process the signaling which are allocated to the UDP ports. Due to the security issues on VoIP devices will consumes extra time for packet delivery and which consumes extra time during the call; so it may delay the packet delivery, due to the encryption and decryption mechanism will conflict the call time. 1.2 Objectives of the study The basic objective of this is to detect source of attacked packet on over network Ø To formally define the network security problems and unauthorized access incidents Ø To define the most accredited security techniques and security methods Ø To evaluate the prototype system and packet feature mechanism Ø Email and other internet message are easily integrated with the voice applications Ø To support the multimedia applications, which provides less cost effective services for video conference, gaming Ø To supports a low cost, flat rate pricing on the voice communication over the Public Internet and Intranet services. Ø Sends the call signaling messages over the IP-based data Network with a suitable quality of service and much superior cost benefit. Ø Present offline message passing between the users by selecting a user from predefined offline user list Ø Present textual communication 1.3 Research Method Ø Provide authentication to the end users for accessing the VoIP services Ø Design secure VoIP Configuration system Ø Attempt to separate VoIP traffic from normal data traffic using either VLANs or a completely separate physical network. Ø Enable authentication on SIP accounts.Internal Firewalls/ACLs should be cond to block telnet and http traffic from reaching voice VLANs or subnets. 1.4 SCOPE These researches analyze the security and performance issues, it has to research on different security levels and represent various security challenges to modern VoIP system. Ø This research enhance security methods by analyzing the modern security challenges Ø To present various security methods; this security methods are explained in chapter -3 to analyze and investigate the security threats and define the solution for obtaining better performance Ø Balance VoIP security and performance by measuring the services and network traffic Ø To present VoIP protocols for secure data transmission 1,5 Thesis Organization Chatper-1: Introduction: General Introduction of VoIP, problem definition and Research methods Chapter -2: Literature Review: Review of VoIP deployment and review of security issues and performance and VoIP security background and security challenges Chapter -3: Security process: VoIP security process, managing of VoIP security and security process and define the security solutions Chapter -4: VOIP security and performance: Demonstrate VoIP performance , balancing of security and performance of VoIP Chapter -5: Analysis Report: security and performance analysis and investigation reports of VoIP security and performance and complete project report scenario Chapter -6: Conclusion, Future Enhancement, References and Appendices. CHAPTER -2 2.0 LITERATURE REVIEW Background VoIP is a IP telephony which is used to deliver a voice on over internet; which stands for Voice over Internet Protocol which converts a voice signals to digital voice packets and transmit these packets on over network; for transmitting which uses Internet protocol for coordinating voice packets. VoIP can be deployed in dissimilar kind of IP enabled network like Internet, wireless networks, Ethernet. VoIP is a telephony system which takes voice as a analog signals and which converts it into digital format and transmit on over network by using Intern protocol. VoIP service Types VoIP provides different types of voice service according to the communication media infrastructure; the most common services are as follows Ø Computer to computer based services Ø PC to phone and phone to PC based services Ø Phone to phone based VoIP services [6] Computer to computer: A voice exchange in between system to system is one type of communication provides free VoIPs services which it requires related software applications such as gtalk[8], skype[7], messengers. In this services the users need to install same softwares in their respective PCs and exchange their voices same as Peer to Peer services. PC to phone and phone to PC: It is a combination of Internet and circuit switched telephone system. The VoIP application software receives the voice and hand over to the Internet protocol to communicate on over telephone network. VoIP services provide a services to communicate with phone s by establishing VoIP network; an applications such as Skype, messengers are communicate to the phones by converting respective receiving and transmitting formats. In the Phone to PC services the user can communicate from phones to PCs; user can dial to PCs by calling like normal phones; in this services the PC IP address contains a phone number. The user can dial from phone to assigned PC IP address phone number; Skype is a best example for this kind of services, which allows users to purchase a VoIP services to communicate from phone to PC [7]. The most common devices in these services are Ø VoIP service providers Ø Modem Ø Internet services Ø ATA: Analog Terminal Adaptor, this convert analog signals to voice signals voice signals to analogs singles Phone to phone based VoIP services [6]: Now a days this type of services are using in long distance calls; many communication service provide companies offering long distance calls in very abnormal price by utilizing the PSTN services. VoIP System A Fig- 1 shows a typical VoIP network topology which is a combination of given equipments; the following equipments are 1) Gatekeeper 2) VoIP Gateway 3) VoIP Clients Gatekeeper: A VoIP gatekeeper is a routing manager and central manager in a H 323 IP telephony surroundings. This is an option in a VoIP system which manages end points of a sector. VoIP gatekeeper is useful for managing calls, terminals and gateways. VoIP gatekeeper presents access control, bandwidth control and address translation. VoIP gateway: The VoIP entry convert a voice calls into genuine instant in between Public switch Telephone Network (PSTN) and IP networks. The basic functionalities of VoIP entry are compression, decompression; signal controlling, packetization and call routing. VoIP clients: This equipment represents phones, multimedia PCs 2.1 Security Issues. VoIP Phishing How To prevent VoIP Phishing and avoided getting Trapped You can do prevent VoIP Phishing at home and in your corporation and to avoid yourself and your associates from being keen as a Phishing victim. What is VoIP Phishing and hoe it work VoIP Phishing is a type of assault that lures the user into given personal data like phone number, credit card numbers, and password over a web site. Phishing over VoIP is become uncontrolled as VoIP makes Phishing easers for attacker. Security thread in VoIP While VoIP has become a one of the conventional communication technologies, VoIP user face a serious of security threads lets see this security issues. Firewall A firewall is software is planned to protect a personal networks from illegal access. Firewalls usually block the worthless passage from the outside to the inside of the networks and so on. Over look security You must not look at only at the light side of VoIP. While it is revolutionizing voice and data communication, it does not symbolize some problematic security issues that need that need to be deal with accurately. Quality of Service Issues (Qos) Qos [9] is a basic process of VoIP; if it delivers a good quality of services to the users which are more advantage to the users for saving money; rather than spending much money on other communication services. The Quality is an importance factor for VoIP services providers industries. In Certain level the security issues implementation can degrade the QoS. The security procedures such as firewalls and encryption techniques block the calls and delay the packet delivery. The main QoS issues are Ø Latency Ø Jitter Ø Packet loss Ø Bandwidth problem Latency: Latency represents a delivery time for voice transmission from source to destination. The ITU-T advice that G.114 [10] establish a many time of constraints on one-way latency .To achieve Quality of Service the VoIP calls must be achieve in a limited bound time. The basic issues in latency are Ø Time spent on routers and long network distance Ø Security measures Ø Voice data encoding Ø Queuing Ø Packetization Ø Composition and decomposition Ø Decoding Jitter: The non-uniform packets make a packet delivery delay; which it is caused by insufficient bandwidth. The packets are in out of sequence order, for transmitting voice media it uses RTP protocol; this protocol are based on UDP so that it makes the packet in out of order sequence which degrades the QoS by not resembling the protocols at protocol level. Packet Loss: The packet loss increase the latency and jitter; where group of packets are arrived late will be discarded and allow new packets. The packet loss is associated with data network; due to the low bandwidth and high traffic which delays the packet delivery. Bandwidth: The low bandwidth delays a packet delivery which degrades the QoS by increasing the latency and jitter. The data on over network have to distribute into various nodes; the data have to transmit from one node to another node during this transmission if it encounter any problem which it can delays the packet. The entire network design includes routers, firewall and other security measures. Certain time in the network path some of the nodes are unavailable at that time it doesnt deliver the packets to an end users. 2.2 VoIP protocols There are numbers and numbers of network that can be working in organize to offer for VoIP communiquà © service .In this part we will center no which the general to the best part of device deploy. Almost each machine in the globe use a standardization called real time protocol (RTP) for transmit of audio and video packet between the networks. IETF is the founder of RPT. The consignment layout of numbers CODE are define in RFC 3551 (The section â€Å"RTP profiles and pay load format specification† of RCF. These sections address items.). Though pay load format section are define in document also published by the ITU (International telecommunication union) and in others IETF RFCs. The RTP mostly deal with issue like packets order and give mechanism to help the address wait. The H.323 [7] standard uses the Internet Engineering Task Force (IETF) RTP protocol to transport media between endpoints. Because of this, H.323 has the same issues as SIP when dealing with network topologies involving NAT. The easiest method is to simply forward the appropriate ports through your NAT device to the internal client. To receive calls, you will always need to forward TCP port 1720 to the client. In addition, you will need to forward the UDP ports for the RTP media and RTCP con-trol streams (see the manual for your device for the port range it requires). Older cli-ents, such as MS Netmeeting, will also require TCP ports forwarded for H.245tunneling (again, see your clients manual for the port number range). If you have a number of clients behind the NAT device, you will need to use a gate-keeper running in proxy mode. The gatekeeper will require an interface attached to the private IP subnet and the public Internet. Your H.323 client on the private IP subnet will then re gister to the gatekeeper, which will proxy calls on the clients behalf. Note that any external clients that wish to call you will also be required to register with the proxy server. At this time, Asterisk cant act as an H.323 gatekeeper. Youll have to use a separate application, such as the open source OpenH323 Gatekeeper H.323 and SIP Have their origins in 1995 as researchers looked to solve the problem of how to computers can indicate communication in order to exchange audio video files.H.323[12] enjoy the first commercial success due to this fact those who are working on the protocol in ITU[12] worked quickly to publish the first standard in the year 1996. While support of the two protocols on a single gateway is critical, another integral part of dual-protocol deployment is the ability for H.323 gatekeepers and SIP proxies to interwork and share routing capabilities. One method that was introduced to support time-to-market requirements uses routing interaction between a Cisco SIP Proxy Server and an H.323 gatekeeper. The business model for some carriers using the Cisco Global Long Distance Solution is to provide origination and termination of voice-over-IP (VoIP) minutes for several other service providers. This business model has been very successful with deployment of H.323-based services, but these Cisco customers would also like to attract additional SIP-based service providers. Ideally, these customers would like to use their existing voice-gateway infrastructure to support additional SIP-based offerings. Cisco has provided these carriers with a way to add new SIP services by adding capabilities to the Cisco SIP Proxy Server to allow it to â€Å"handshake† with an H.323 gatekeeper using the H.323 RAS protocol. By enabling a SIP proxy server to communicate with an H.323 gatekeeper using RAS location request, location confirmation, and location reject messages and responses, a Cisco SIP Proxy Server can obtain optimized routing information from VoIP gateways that have been deployed in the service providers network. The Cisco architecture allows for protocol exibility and enables, one call-by-call basis, use of a particular session protocol. This exibility allows customers to deploy SIP networks on proven packet telephony infrastructures, while still maintaining core H.323 functionality within their networks. With the ability to support the connection of customers and carriers using either rotocol, service providers can offer a variety of application hosting and sharing services, and be more aggressive in pursuing wholesale opportunities via new services. Some principles for coexistence that are critical for successful multiprotocol deployments are transport capabilities across time-division multiplexing (TDM) interfaces, dual tone multifrequency (DTMF) processing capabilities and fax relay support. In deployments where both protocols are used, it is important that there are no performance limitations related to the call mix between SIP and H.323 calls, and that there is no significant deviation in calls-per-second measurements compared to a homogeneous SIP or H.323 network. Cisco gateways provide support for coexistence of SIP and H.323 calls beginning with Cisco IOS Software Release 12.2(2)XB. Above illustrates packet voice architectures for wholesale call transport and 2 illustrates termination services for application service providers (ASPs) where SIP and H.323 are used simultaneously for signaling. Reasons for VoIP Deployment When you are using PSTN line, you typically pay for time used to a PSTN line manager company: more time you stay at phone and more youll pay. In addition you couldnt talk with other that one person at a time. In opposite with VoIP mechanism you can talk all the time with every person you want (the needed is that other person is also connected to Internet at the same time), as far as you want (money independent) and, in addition, you can talk with many people at the same time. If youre still not persuaded you can consider that, at the same time, you can exchange data with people are you talking with, sending images, graphs and videos. There are two main reasons to use VoIP: lower cost than traditional landline telephone and diverse value-added services. Low Cost Higher multimedia application: Traditional telephone system requires highly trained technicians to install and custom configuration. Companies find the need to call the service of specialist to implement, simple tasks like moving adding a phone. Modules such as ‘voicemail and the additional lines are the part of perpetual cycle of upgrades and modifications that make telephony support a very profitable business. The methodology use to implement PSTN business phone system is well understood and the industry is very mature. Hence company can make a purchase with the confidence that if they are installing a traditional system it will function and include an excellent supported infrastructure. IDC reports the number of VoIP ports shipped in 2005 will be equal to traditional analogues deployment. Non to be taken lightly, the average lifespan of a voice system range from 5-10 years. In 5 to 10 years, an analogues telephone system will be the exception as opposed to the telephone standards. Qualified technicians, whom are required to work on propriety system, will be difficult to come by. In addition, the prospect of telephone manufacture going out of business or the technology simply being repulsed by a more agile and less costly alternative, are both risks that must be taken into account in well informed decision. Fortunately a company can take few preventive to protect them from outdated system. One such step is use of standards technologies that are back by a number of company and possibly trade group as opposed to a single entity. In VoIP space a good example is session Initiation Protocols, SIP. SIP is supported by the large majority of vendors and is considered the industry standard protocol for VoIP. Beyond analogue lines that terminate from an ISP, The traditional telephony market does not have much interoperability. For example it is not be integrate an Avaya PBX with a Nortel PBX. Hidden cost can be substantial in any technology deployment. The downtime experienced with buggy or poorly implemented technology, in addition to the cost of qualified consultants to remedy such as Challenges of VoIP: Though VoIP is becoming more and more popular, there are still some challenging problems with VoIP: Bandwidth: Network which available is an important anxiety in network. A network can be busted down into many nodes, associations and produce a big quantity of traffic flow, therefore, the availability of each node and link where we only focus on the bandwidth of the VoIP system. An in a data network, bandwidth overcrowding can cause QoS problems, when network overcrowding occur, packets need to be queued which cause latency as well as jitter. Thus, bandwidth must be accurately reserved and billed to ensure VoIP quality. Because data and voice share the same network bandwidth in a VOIP system, the necessary bandwidth condition and allocation become more complex. In a LAN surroundings, switches usually running at 100 Mbps (or 1000 Mbps), upgrading routers and switches can be the effective ways to address the bandwidth bottleneck inside the LAN. Power Failure and Backup Systems: Traditional telephones work on 48 volts which is supplied by the telephone line itself without outside power supply. Thus, traditional telephones can still continue to work even when a power breakdown occurs. However, a backup power system is also required with VOIP so that they can continue to operate during a power breakdown. An organization usually has an uninterruptible power system (UPS) for its network to overcome power failure, [14] Security: As VoIP becomes too popular, the issues related to VoIP network are also very progressively and more arising [15]. W. Chou [16] has investigation the different security of VoIP investigation the different and also given some optional strategies for these issues. In reference [17], the authors also outline the challenges of securing VoIP, and provide guidelines for adopting VoIP technology. Soft phone: Soft phones are installed on system thus should not be used where the security is an anxiety. In todays world, worms, viruses, Trojan houses, spy wares and etc are everywhere on the internet and very complex to defend. A computer could be attacked even if a user does not open the email attachment, or a user does nothing but only visit a compromise web site. Thus use of soft phones could bring high risks for vulnerabilities. Emergency calls: Each traditional telephone link is joined to a physical location, thus emergency tune-up providers can easily track callers locality to the emergency send out office. But dissimilar traditional telephone lines, VoIP technology allows an exacting number could be from anywhere; this made emergency services more problematical, because these emergency call centers cannot get the callers location or it may not be possible to send out emergency services to that location. Although the VoIP providers provide some solutions for emergency calls, there is at rest need of manufacturing principles in VOIP surroundings. Physical security: The most significant issue in VoIP network is Physical security. An attacker can do traffic psychoanalysis once actually they access to VoIP. In between server and gateway, like to determine which parties are communicating. So the physical security policy and some controls are needed to control the VoIP network access mechanism. Otherwise, risks such as insertion of snuffer software by attackers could cause data and all voice connections being intercept. Wireless Security: Connection in wireless network nodes were integrated with VoIP network which receives more and more popular and accepted [18]. The wireless networks are very feeble as compared to Wired Equivalent Privacy (WEP). The algorithm for 802.11 is week because WEP can be cracked with public available software. This is the major project in wireless network for example the more common and popular WiFi protected Access (WPF and WPA 20) which administrated by Wi-Fi Alliance are providing more significant security in improvement, the WPA protected is also integrated with wireless technology in VoIP. CHAPTER -3 Related Work 3.0 Security Studies Voice of Internet Protocol is the next generation telecommunications method. It allows to phone calls to be route over a data network thus saving money and offering increased features and productivity. All these benefits come at a price, vulnerability. It is easier to attack and exploit a voice and data network. VoIP will need extra security measures beyond the standard security that is typically implement for a computer network. Many issues need to be addressed such as type of attacks, security, quality of service and VoIP protocols. Voice over IP (VoIP) is a one of the most challenging technology in todays market. The importance of VoIP is rapidly growing, many vendors introducing VoIP services with advanced technologies for improving quality of services and security. In this chapter I am discussing about security models and security process. 3.1 VoIP Security Process: There are many VoIP protocols in the market. Some are proprietary while others are open standards. The two most popular open protocols are H.323 and SIP. They were designed by two different organizations and operate slightly differently. They both have problems with the use of random ports problems with NAT translations and firewalls. Security for VoIP devices and VoIP network is a complex process, securing of VoIP protocols and data streaming invokes at many stages. The most common VoIP vulnerabilities are as follows Ø Software Related: Ø Device related Ø Protocol related Ø System Configuration related Ø Application level attacks 3.1.2 Software Related Vulnerabilities: The basic flaws in software vulnerable are operating services and functions problems and quality, operating system interface and administrations [19]. Software application interfaces, software application logic Ø Software applications Ø Application interfaces 3.1.3 Device Related Vulnerabilities: One of the most common security threats effects on VoIP hardware devices. In early days the most of the VoIP systems are designed with limited energy power, computing power. Due to the heavy competition in the market many vendors are keeping low cost, they are designing with low cast VoIP hardware devices but due to the changes of software applications, other system infrastructure the system need to regularly updates the device. The most common hardware devices in VoIP are Ø PCs Ø Telephone adaptors Ø Modems Ø VoIP phones 3.1.4 Protocol Vulnerability: The main protocols in VoIP are H.323 [12] and SIP (Session initiation protocol), these two protocols are commonly used in VoIP hardware system [19]. These protocols overwhelmed with security issues. SIP protocol is a complex protocol which maintains the security in SIP RFC. In SIP the network address translation crack security and which doesnt examine firewalls. H.323 is an International Telecommunication Union standard for audio and video communication across a packet network (National Institute of Standards and Technology 2005). There are four types of devices under H.324: terminals, Gateways, Gatekeepers and Multi-Point Conference Units. The terminals are phones and computers. Gateway provides an exit to other networks. The Gatekeeper handles addressing and call routing while the MCU provided conference call support. H.323 uses other protocols to perform other vital tasks. UDP packets using the Real-Time Transport Protocol transport all data. H.225 handles registration, admissions status, and call signaling. H.235 also handles all security and has four different schemes call Annexes. â€Å"H.323 is a complicated protocol†. SIP Vulnerabilities Overview The below shows a SIP call flow using SIP and UDP protocols, user can send a voice call through proxy server, the p Voice over Internet Protocol (VoIP) Technology Voice over Internet Protocol (VoIP) Technology ABSTRACT: Voice over Internet Protocol (VoIP) technology which attract extra attention and awareness to the world wide business. IP telephonys system will affect the sending voice transmission in the form of packet over the IP network in the VoIP applications. Now a days many industries will use the VoIP technologies to provide the Security. In this project, I provided a variety of VoIP safety intimidation and probable approach to handle the intimidation in VoIP application. VoIP is naturally susceptible to networks attack, like hateful codes (i.e., worms, viruses, Trojans), denial-of-service (DoS), distributed DoS (DDoS), pharming, and (though non malicious) sparkle were crowded. These attacks also spoil grimy system by overriding assets, distracting valid user, compromise private informations, or by demeaning code and records. This break affect the contaminated system, it also destroy the unaffected (or even non-vulnerable) ones. All system associated to the Internet are responsive to hateful code which try to contaminate as much as hosts is probable, cause overcrowding on the network communications. The QoS which is provide to the end user is of highest significance and it is the main issue to implement the VoIP system, since if the exchange is indecipherable then there is no position in giving the service. The major factor which distresses the superiority of services is Latency, Jitter and Packet loss. CHAPTER-1 1.0 Introduction The voice enterprises continuously providing voice conversation services on over broad band by discovering the current market issues and network issues from past 20 years, the voice transition industry undergone various security and network issues to produce better quality voice service to transit on over broad band. The current voice market has been step up into the new level of voice protocols for providing VoIP services during low bandwidth, high level of data and voice transmission provisions. The VOIP technologies allow sharing the resource of WAN for supporting data and voice for saving the cost for transmission process [1]. The VoIP provides many advantages to the enterprises, the migration of voice and telephone application form TDM switch network to IP packet switched network provides many advantages to enterprises during the migration of voice into IP application the enterprises need to provide security to the data applications [2]. However the enterprises need to identify the security issues and employee new techniques to protect against attacks. Security and QoS is a main aspect of VOIP system, the data on voice networks have been attacked by viruses, worms, DOS attacks and other unknown authentication users [3]. The VOIP architecture is a complete network hierarchical structure which is compound with many of the networking devices, the design structure have to ensure that whether the components will cope the unwanted attacks. The protocol structure in a VOIP system is a more sensible factor due to the poor ambitious. Here we introduce the attacks on over VoIP system. VOIP Overview VoIP stands for Voice over Internet Protocol which is the mainly used in the transmission of voice communications through IP network like internet, public switched networks [4]. The concept of VoIP mainly targets of the transmission of voice based messages and applications by using different protocols and is transmitted via the internet. The basic steps involved in the transmission of voice signals through the internet are:  · Conversion of voice to analog and digital signal.  · Compression and conversion of the signal into Internet Protocol Packets to broadcast over Internet. VoIP systems adopt different session control protocols for commanding over the set-up, tear-down of calls and also different audio codecs which allow for encoding the voice signal and allow the transmission. These audio codecs may vary form system to system where some of them are based on the narrow band and some on the compressed speech where some other system may use high fidelity audio codecs. Technologies used to implement VoIP:  · H.323 [12]  · IP Multimedia Subsystem (IMS)  · Session initiation Protocol (SIP) [5]  · Real-time Transport Protocol (RTP) [5] 1.1 Problem Definition In the past days the VoIP security is a not a big concern the people were mainly concerned with the functionalities, cost and the usage, but the VOIP communication trend has been encouraged; the VOIP communication system widely accepted by the people; due to the high acceptance of VOIP system the security issues are main concern. However the VoIP services are rapidly growing in the current voice communication system, many unauthenticated users and hackers are stealing the VoIP services and hacking the services from the service providers and re routing to their personal usage. Some of the security standards are not credential they only supports to authentication over calls, but the problem with the service theft. The security concerns will affect on quality of the system, due to the security tools and security solutions will conflict on quality of service. The system will accept the security tools those tools shouldnt decrease the quality. The basic issue of the quality is firewall. The firewall will blocks the calls for security constrains it will not process the signaling which are allocated to the UDP ports. Due to the security issues on VoIP devices will consumes extra time for packet delivery and which consumes extra time during the call; so it may delay the packet delivery, due to the encryption and decryption mechanism will conflict the call time. 1.2 Objectives of the study The basic objective of this is to detect source of attacked packet on over network Ø To formally define the network security problems and unauthorized access incidents Ø To define the most accredited security techniques and security methods Ø To evaluate the prototype system and packet feature mechanism Ø Email and other internet message are easily integrated with the voice applications Ø To support the multimedia applications, which provides less cost effective services for video conference, gaming Ø To supports a low cost, flat rate pricing on the voice communication over the Public Internet and Intranet services. Ø Sends the call signaling messages over the IP-based data Network with a suitable quality of service and much superior cost benefit. Ø Present offline message passing between the users by selecting a user from predefined offline user list Ø Present textual communication 1.3 Research Method Ø Provide authentication to the end users for accessing the VoIP services Ø Design secure VoIP Configuration system Ø Attempt to separate VoIP traffic from normal data traffic using either VLANs or a completely separate physical network. Ø Enable authentication on SIP accounts.Internal Firewalls/ACLs should be cond to block telnet and http traffic from reaching voice VLANs or subnets. 1.4 SCOPE These researches analyze the security and performance issues, it has to research on different security levels and represent various security challenges to modern VoIP system. Ø This research enhance security methods by analyzing the modern security challenges Ø To present various security methods; this security methods are explained in chapter -3 to analyze and investigate the security threats and define the solution for obtaining better performance Ø Balance VoIP security and performance by measuring the services and network traffic Ø To present VoIP protocols for secure data transmission 1,5 Thesis Organization Chatper-1: Introduction: General Introduction of VoIP, problem definition and Research methods Chapter -2: Literature Review: Review of VoIP deployment and review of security issues and performance and VoIP security background and security challenges Chapter -3: Security process: VoIP security process, managing of VoIP security and security process and define the security solutions Chapter -4: VOIP security and performance: Demonstrate VoIP performance , balancing of security and performance of VoIP Chapter -5: Analysis Report: security and performance analysis and investigation reports of VoIP security and performance and complete project report scenario Chapter -6: Conclusion, Future Enhancement, References and Appendices. CHAPTER -2 2.0 LITERATURE REVIEW Background VoIP is a IP telephony which is used to deliver a voice on over internet; which stands for Voice over Internet Protocol which converts a voice signals to digital voice packets and transmit these packets on over network; for transmitting which uses Internet protocol for coordinating voice packets. VoIP can be deployed in dissimilar kind of IP enabled network like Internet, wireless networks, Ethernet. VoIP is a telephony system which takes voice as a analog signals and which converts it into digital format and transmit on over network by using Intern protocol. VoIP service Types VoIP provides different types of voice service according to the communication media infrastructure; the most common services are as follows Ø Computer to computer based services Ø PC to phone and phone to PC based services Ø Phone to phone based VoIP services [6] Computer to computer: A voice exchange in between system to system is one type of communication provides free VoIPs services which it requires related software applications such as gtalk[8], skype[7], messengers. In this services the users need to install same softwares in their respective PCs and exchange their voices same as Peer to Peer services. PC to phone and phone to PC: It is a combination of Internet and circuit switched telephone system. The VoIP application software receives the voice and hand over to the Internet protocol to communicate on over telephone network. VoIP services provide a services to communicate with phone s by establishing VoIP network; an applications such as Skype, messengers are communicate to the phones by converting respective receiving and transmitting formats. In the Phone to PC services the user can communicate from phones to PCs; user can dial to PCs by calling like normal phones; in this services the PC IP address contains a phone number. The user can dial from phone to assigned PC IP address phone number; Skype is a best example for this kind of services, which allows users to purchase a VoIP services to communicate from phone to PC [7]. The most common devices in these services are Ø VoIP service providers Ø Modem Ø Internet services Ø ATA: Analog Terminal Adaptor, this convert analog signals to voice signals voice signals to analogs singles Phone to phone based VoIP services [6]: Now a days this type of services are using in long distance calls; many communication service provide companies offering long distance calls in very abnormal price by utilizing the PSTN services. VoIP System A Fig- 1 shows a typical VoIP network topology which is a combination of given equipments; the following equipments are 1) Gatekeeper 2) VoIP Gateway 3) VoIP Clients Gatekeeper: A VoIP gatekeeper is a routing manager and central manager in a H 323 IP telephony surroundings. This is an option in a VoIP system which manages end points of a sector. VoIP gatekeeper is useful for managing calls, terminals and gateways. VoIP gatekeeper presents access control, bandwidth control and address translation. VoIP gateway: The VoIP entry convert a voice calls into genuine instant in between Public switch Telephone Network (PSTN) and IP networks. The basic functionalities of VoIP entry are compression, decompression; signal controlling, packetization and call routing. VoIP clients: This equipment represents phones, multimedia PCs 2.1 Security Issues. VoIP Phishing How To prevent VoIP Phishing and avoided getting Trapped You can do prevent VoIP Phishing at home and in your corporation and to avoid yourself and your associates from being keen as a Phishing victim. What is VoIP Phishing and hoe it work VoIP Phishing is a type of assault that lures the user into given personal data like phone number, credit card numbers, and password over a web site. Phishing over VoIP is become uncontrolled as VoIP makes Phishing easers for attacker. Security thread in VoIP While VoIP has become a one of the conventional communication technologies, VoIP user face a serious of security threads lets see this security issues. Firewall A firewall is software is planned to protect a personal networks from illegal access. Firewalls usually block the worthless passage from the outside to the inside of the networks and so on. Over look security You must not look at only at the light side of VoIP. While it is revolutionizing voice and data communication, it does not symbolize some problematic security issues that need that need to be deal with accurately. Quality of Service Issues (Qos) Qos [9] is a basic process of VoIP; if it delivers a good quality of services to the users which are more advantage to the users for saving money; rather than spending much money on other communication services. The Quality is an importance factor for VoIP services providers industries. In Certain level the security issues implementation can degrade the QoS. The security procedures such as firewalls and encryption techniques block the calls and delay the packet delivery. The main QoS issues are Ø Latency Ø Jitter Ø Packet loss Ø Bandwidth problem Latency: Latency represents a delivery time for voice transmission from source to destination. The ITU-T advice that G.114 [10] establish a many time of constraints on one-way latency .To achieve Quality of Service the VoIP calls must be achieve in a limited bound time. The basic issues in latency are Ø Time spent on routers and long network distance Ø Security measures Ø Voice data encoding Ø Queuing Ø Packetization Ø Composition and decomposition Ø Decoding Jitter: The non-uniform packets make a packet delivery delay; which it is caused by insufficient bandwidth. The packets are in out of sequence order, for transmitting voice media it uses RTP protocol; this protocol are based on UDP so that it makes the packet in out of order sequence which degrades the QoS by not resembling the protocols at protocol level. Packet Loss: The packet loss increase the latency and jitter; where group of packets are arrived late will be discarded and allow new packets. The packet loss is associated with data network; due to the low bandwidth and high traffic which delays the packet delivery. Bandwidth: The low bandwidth delays a packet delivery which degrades the QoS by increasing the latency and jitter. The data on over network have to distribute into various nodes; the data have to transmit from one node to another node during this transmission if it encounter any problem which it can delays the packet. The entire network design includes routers, firewall and other security measures. Certain time in the network path some of the nodes are unavailable at that time it doesnt deliver the packets to an end users. 2.2 VoIP protocols There are numbers and numbers of network that can be working in organize to offer for VoIP communiquà © service .In this part we will center no which the general to the best part of device deploy. Almost each machine in the globe use a standardization called real time protocol (RTP) for transmit of audio and video packet between the networks. IETF is the founder of RPT. The consignment layout of numbers CODE are define in RFC 3551 (The section â€Å"RTP profiles and pay load format specification† of RCF. These sections address items.). Though pay load format section are define in document also published by the ITU (International telecommunication union) and in others IETF RFCs. The RTP mostly deal with issue like packets order and give mechanism to help the address wait. The H.323 [7] standard uses the Internet Engineering Task Force (IETF) RTP protocol to transport media between endpoints. Because of this, H.323 has the same issues as SIP when dealing with network topologies involving NAT. The easiest method is to simply forward the appropriate ports through your NAT device to the internal client. To receive calls, you will always need to forward TCP port 1720 to the client. In addition, you will need to forward the UDP ports for the RTP media and RTCP con-trol streams (see the manual for your device for the port range it requires). Older cli-ents, such as MS Netmeeting, will also require TCP ports forwarded for H.245tunneling (again, see your clients manual for the port number range). If you have a number of clients behind the NAT device, you will need to use a gate-keeper running in proxy mode. The gatekeeper will require an interface attached to the private IP subnet and the public Internet. Your H.323 client on the private IP subnet will then re gister to the gatekeeper, which will proxy calls on the clients behalf. Note that any external clients that wish to call you will also be required to register with the proxy server. At this time, Asterisk cant act as an H.323 gatekeeper. Youll have to use a separate application, such as the open source OpenH323 Gatekeeper H.323 and SIP Have their origins in 1995 as researchers looked to solve the problem of how to computers can indicate communication in order to exchange audio video files.H.323[12] enjoy the first commercial success due to this fact those who are working on the protocol in ITU[12] worked quickly to publish the first standard in the year 1996. While support of the two protocols on a single gateway is critical, another integral part of dual-protocol deployment is the ability for H.323 gatekeepers and SIP proxies to interwork and share routing capabilities. One method that was introduced to support time-to-market requirements uses routing interaction between a Cisco SIP Proxy Server and an H.323 gatekeeper. The business model for some carriers using the Cisco Global Long Distance Solution is to provide origination and termination of voice-over-IP (VoIP) minutes for several other service providers. This business model has been very successful with deployment of H.323-based services, but these Cisco customers would also like to attract additional SIP-based service providers. Ideally, these customers would like to use their existing voice-gateway infrastructure to support additional SIP-based offerings. Cisco has provided these carriers with a way to add new SIP services by adding capabilities to the Cisco SIP Proxy Server to allow it to â€Å"handshake† with an H.323 gatekeeper using the H.323 RAS protocol. By enabling a SIP proxy server to communicate with an H.323 gatekeeper using RAS location request, location confirmation, and location reject messages and responses, a Cisco SIP Proxy Server can obtain optimized routing information from VoIP gateways that have been deployed in the service providers network. The Cisco architecture allows for protocol exibility and enables, one call-by-call basis, use of a particular session protocol. This exibility allows customers to deploy SIP networks on proven packet telephony infrastructures, while still maintaining core H.323 functionality within their networks. With the ability to support the connection of customers and carriers using either rotocol, service providers can offer a variety of application hosting and sharing services, and be more aggressive in pursuing wholesale opportunities via new services. Some principles for coexistence that are critical for successful multiprotocol deployments are transport capabilities across time-division multiplexing (TDM) interfaces, dual tone multifrequency (DTMF) processing capabilities and fax relay support. In deployments where both protocols are used, it is important that there are no performance limitations related to the call mix between SIP and H.323 calls, and that there is no significant deviation in calls-per-second measurements compared to a homogeneous SIP or H.323 network. Cisco gateways provide support for coexistence of SIP and H.323 calls beginning with Cisco IOS Software Release 12.2(2)XB. Above illustrates packet voice architectures for wholesale call transport and 2 illustrates termination services for application service providers (ASPs) where SIP and H.323 are used simultaneously for signaling. Reasons for VoIP Deployment When you are using PSTN line, you typically pay for time used to a PSTN line manager company: more time you stay at phone and more youll pay. In addition you couldnt talk with other that one person at a time. In opposite with VoIP mechanism you can talk all the time with every person you want (the needed is that other person is also connected to Internet at the same time), as far as you want (money independent) and, in addition, you can talk with many people at the same time. If youre still not persuaded you can consider that, at the same time, you can exchange data with people are you talking with, sending images, graphs and videos. There are two main reasons to use VoIP: lower cost than traditional landline telephone and diverse value-added services. Low Cost Higher multimedia application: Traditional telephone system requires highly trained technicians to install and custom configuration. Companies find the need to call the service of specialist to implement, simple tasks like moving adding a phone. Modules such as ‘voicemail and the additional lines are the part of perpetual cycle of upgrades and modifications that make telephony support a very profitable business. The methodology use to implement PSTN business phone system is well understood and the industry is very mature. Hence company can make a purchase with the confidence that if they are installing a traditional system it will function and include an excellent supported infrastructure. IDC reports the number of VoIP ports shipped in 2005 will be equal to traditional analogues deployment. Non to be taken lightly, the average lifespan of a voice system range from 5-10 years. In 5 to 10 years, an analogues telephone system will be the exception as opposed to the telephone standards. Qualified technicians, whom are required to work on propriety system, will be difficult to come by. In addition, the prospect of telephone manufacture going out of business or the technology simply being repulsed by a more agile and less costly alternative, are both risks that must be taken into account in well informed decision. Fortunately a company can take few preventive to protect them from outdated system. One such step is use of standards technologies that are back by a number of company and possibly trade group as opposed to a single entity. In VoIP space a good example is session Initiation Protocols, SIP. SIP is supported by the large majority of vendors and is considered the industry standard protocol for VoIP. Beyond analogue lines that terminate from an ISP, The traditional telephony market does not have much interoperability. For example it is not be integrate an Avaya PBX with a Nortel PBX. Hidden cost can be substantial in any technology deployment. The downtime experienced with buggy or poorly implemented technology, in addition to the cost of qualified consultants to remedy such as Challenges of VoIP: Though VoIP is becoming more and more popular, there are still some challenging problems with VoIP: Bandwidth: Network which available is an important anxiety in network. A network can be busted down into many nodes, associations and produce a big quantity of traffic flow, therefore, the availability of each node and link where we only focus on the bandwidth of the VoIP system. An in a data network, bandwidth overcrowding can cause QoS problems, when network overcrowding occur, packets need to be queued which cause latency as well as jitter. Thus, bandwidth must be accurately reserved and billed to ensure VoIP quality. Because data and voice share the same network bandwidth in a VOIP system, the necessary bandwidth condition and allocation become more complex. In a LAN surroundings, switches usually running at 100 Mbps (or 1000 Mbps), upgrading routers and switches can be the effective ways to address the bandwidth bottleneck inside the LAN. Power Failure and Backup Systems: Traditional telephones work on 48 volts which is supplied by the telephone line itself without outside power supply. Thus, traditional telephones can still continue to work even when a power breakdown occurs. However, a backup power system is also required with VOIP so that they can continue to operate during a power breakdown. An organization usually has an uninterruptible power system (UPS) for its network to overcome power failure, [14] Security: As VoIP becomes too popular, the issues related to VoIP network are also very progressively and more arising [15]. W. Chou [16] has investigation the different security of VoIP investigation the different and also given some optional strategies for these issues. In reference [17], the authors also outline the challenges of securing VoIP, and provide guidelines for adopting VoIP technology. Soft phone: Soft phones are installed on system thus should not be used where the security is an anxiety. In todays world, worms, viruses, Trojan houses, spy wares and etc are everywhere on the internet and very complex to defend. A computer could be attacked even if a user does not open the email attachment, or a user does nothing but only visit a compromise web site. Thus use of soft phones could bring high risks for vulnerabilities. Emergency calls: Each traditional telephone link is joined to a physical location, thus emergency tune-up providers can easily track callers locality to the emergency send out office. But dissimilar traditional telephone lines, VoIP technology allows an exacting number could be from anywhere; this made emergency services more problematical, because these emergency call centers cannot get the callers location or it may not be possible to send out emergency services to that location. Although the VoIP providers provide some solutions for emergency calls, there is at rest need of manufacturing principles in VOIP surroundings. Physical security: The most significant issue in VoIP network is Physical security. An attacker can do traffic psychoanalysis once actually they access to VoIP. In between server and gateway, like to determine which parties are communicating. So the physical security policy and some controls are needed to control the VoIP network access mechanism. Otherwise, risks such as insertion of snuffer software by attackers could cause data and all voice connections being intercept. Wireless Security: Connection in wireless network nodes were integrated with VoIP network which receives more and more popular and accepted [18]. The wireless networks are very feeble as compared to Wired Equivalent Privacy (WEP). The algorithm for 802.11 is week because WEP can be cracked with public available software. This is the major project in wireless network for example the more common and popular WiFi protected Access (WPF and WPA 20) which administrated by Wi-Fi Alliance are providing more significant security in improvement, the WPA protected is also integrated with wireless technology in VoIP. CHAPTER -3 Related Work 3.0 Security Studies Voice of Internet Protocol is the next generation telecommunications method. It allows to phone calls to be route over a data network thus saving money and offering increased features and productivity. All these benefits come at a price, vulnerability. It is easier to attack and exploit a voice and data network. VoIP will need extra security measures beyond the standard security that is typically implement for a computer network. Many issues need to be addressed such as type of attacks, security, quality of service and VoIP protocols. Voice over IP (VoIP) is a one of the most challenging technology in todays market. The importance of VoIP is rapidly growing, many vendors introducing VoIP services with advanced technologies for improving quality of services and security. In this chapter I am discussing about security models and security process. 3.1 VoIP Security Process: There are many VoIP protocols in the market. Some are proprietary while others are open standards. The two most popular open protocols are H.323 and SIP. They were designed by two different organizations and operate slightly differently. They both have problems with the use of random ports problems with NAT translations and firewalls. Security for VoIP devices and VoIP network is a complex process, securing of VoIP protocols and data streaming invokes at many stages. The most common VoIP vulnerabilities are as follows Ø Software Related: Ø Device related Ø Protocol related Ø System Configuration related Ø Application level attacks 3.1.2 Software Related Vulnerabilities: The basic flaws in software vulnerable are operating services and functions problems and quality, operating system interface and administrations [19]. Software application interfaces, software application logic Ø Software applications Ø Application interfaces 3.1.3 Device Related Vulnerabilities: One of the most common security threats effects on VoIP hardware devices. In early days the most of the VoIP systems are designed with limited energy power, computing power. Due to the heavy competition in the market many vendors are keeping low cost, they are designing with low cast VoIP hardware devices but due to the changes of software applications, other system infrastructure the system need to regularly updates the device. The most common hardware devices in VoIP are Ø PCs Ø Telephone adaptors Ø Modems Ø VoIP phones 3.1.4 Protocol Vulnerability: The main protocols in VoIP are H.323 [12] and SIP (Session initiation protocol), these two protocols are commonly used in VoIP hardware system [19]. These protocols overwhelmed with security issues. SIP protocol is a complex protocol which maintains the security in SIP RFC. In SIP the network address translation crack security and which doesnt examine firewalls. H.323 is an International Telecommunication Union standard for audio and video communication across a packet network (National Institute of Standards and Technology 2005). There are four types of devices under H.324: terminals, Gateways, Gatekeepers and Multi-Point Conference Units. The terminals are phones and computers. Gateway provides an exit to other networks. The Gatekeeper handles addressing and call routing while the MCU provided conference call support. H.323 uses other protocols to perform other vital tasks. UDP packets using the Real-Time Transport Protocol transport all data. H.225 handles registration, admissions status, and call signaling. H.235 also handles all security and has four different schemes call Annexes. â€Å"H.323 is a complicated protocol†. SIP Vulnerabilities Overview The below shows a SIP call flow using SIP and UDP protocols, user can send a voice call through proxy server, the p

If There Were a Draft :: essays research papers

If There Were a Draft   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  It is complicated not to intelligently discuss the future of our military involvement with Iraq without the notion of a draft to arise. Although our presidential candidates and other government officials shun the issue of a draft and avidly display their negativity towards the idea, it is a feasible inquiry to ponder. What if there is indeed a draft? I, being a 16 year old student, know that if there ever is such a military draft, my particular age range would be in target for a good thirteen or fourteen years. I have contemplated the hypothetical scenario of myself, many years from now, being a mere 19-year old boy, opening a letter that summons me to take part in duty for my country; what would I do?   Ã‚  Ã‚  Ã‚  Ã‚  I can imagine myself opening that letter, and the feel of my young heart sinking into my chest. I am not made for war. I am not even made for football. I am not political and I certainly am not pro-war. I would see this call to arms as a call for the worst. Our country has finally had to fall upon scooping those who did not enlist out of there homes and into the arms of the great American machine of violence and destruction. Ultimately, I believe, there would be nothing for me to do. I would go. What are my other options? I would never leave or hide away. Whether it was legal or not, I would not run from a draft. Although I would never enlist, if my country asked me to go overseas, I believe that I would. I would go because there is a great deal of respect earned in becoming part of the military. In the long run, it would be much more beneficial to take part in it rather to run from it. To run, I feel, would be cowardly. Although I would be terrified, I would still go.

Children and the Effects of Television Essay

Television programs were created for children to learn everyday skills, but it can come to start affecting children today because they watch too much they start lacking in physical activity and some can become distant and violent. Studies have shown that children can become obese, violent and even dependent on television if watched too much television. Television can influence children in many different ways like becoming obese, become dependent on it too much; change school habits and even can become violent with watching different types of shows. It is time for parents to start standing up and take control over what and just how much their children watch television. It is said that children watch too much television even though some studies have proven that different types of children’s television shows tend to effect children in different ways also they learn new things faster. Shows like Blue’s Clues, Chuggington, Dinosaur Train, Mickey Mouse Club House, and Team Umizoomi are all filled with educational values that help children develop skills that they need. Blue’s Clues is a much liked show by children ages 2-4. According to â€Å"Common Sense Media† (2012), â€Å"In fact, Blue’s Clues does a very fine job of treating its young viewers as the multifaceted individuals that they are.† T his is very important to young children because it makes them feel as they are a part of something special when they watch shows like this. With these types of shows teach children how to have different types of important social skills, teamwork, science, alphabet, numbers, math problems and even have physical fitness in them which are some of the things that a child needs to know. With these types of show is just what children need to help them expand their brains. According to PEDÃÅ"K (2012) â€Å"Whichever program it may be, it has behavioral, mental and emotional effects.† (p.224).On the other hand more children are watching more television shows for an entertainment purpose which has no educational vales in them. Shows like Sponge Bob Square Pants, The Simpsons, Batman, and The Teenage Mutant Ninja Turtles which consist of having violence, rudeness, and poor role models for children are the ones that are shaping our children in this day of age. It is up to the parent to make sure that their children are getting the correct balance of fun, education, and physical activity to help them grow. Studies have shown that cartoons have the most major impacts on children because in the cartoons to children it is something done every day and ok to act out likes the character on television. According to â€Å"Kids Health from Nemours† (1995-2012),† Kids who view violent acts are more likely to show aggressive behavior† which has become an issue to many different children around the world today. Children are like little sponges soaking up everything they can because every little boy and girl wants to be like their favorite cartoon hero or character. How much time a child watches television is a major factor in children’s behavior and their physical health. Whenever parents allow their children to sit in front of the television and watch more than four hours a day then parents could be running a risk of their child to become more dependent on television to keep them entertained, and this can become very harmful to a child’s health, or to their mental state as well. It can be hard on a parent try to clean house, cook a meal, and even do school work with children becoming bored, and parents just do not have the time to spend with them and then so it seem to be a helpful tool to be able to help at the time for them to watch television. One of the things that you can do to make sure when the appropriate times and what is the appropriate show’s to watch according to â€Å"Kids Health from Nemours† (1995-2012),† Come up with a family TV schedule that you all agree upon each week. Then, post the schedule in a visible area (e.g., on the refrigerator) so that everyone knows which programs are OK to watch and when. And make sure to turn off the TV when the â€Å"scheduled† program is over instead of channel surfing.† Instead of giving your children television time when they experience boredom some suggestion to them is to go outside and make believe that they are the characters in their favorite learning television show. Another thing is get them some flash cards with math, spelling or any type of learning cards. If you distract children from television with something better then you will have a child that cares less about the television and more about playing with their learning games. Common assumption say that violent television shows can mold a child to be either violent when they get older or they develop a fear of being hurt. Children take what they see and apply it to what they do, kind of like the saying â€Å"Monkey see monkey do† type of thing. According to Willson (2008) â€Å"Wilson also shows that children’s susceptibility to media influence can vary according to their gender, their age, how realistic they perceive the media to be, and how much they identify with characters and people on the screen.† † (p. 87) Children need positive role models in their life and someone to look up to in life and most children have their television characters. Parents can usually see the signs in a child just by the way they are when watching a certain television show, and the way that they act if they cannot see the television show is a sign that a parent needs to watch the television show to see what it is that is addicting about the show to their child to make them act out. There are many different types of signs to help parents know if the show that your child is watching is appropriate for them or if it is not appropriate for them. Some of the signs that parents want to look for is if they have trouble in school, with drawn away from friends and family just to name a few, and if you see these problems then as a parent should step in and try to pull the child/children away from the television shows that they watch. Some say that it cannot be done but studies have shown that if there is more quality time spent between parents and their child/children then they will more than likely not have the desire to watch television. Over the past 2 weeks I have been conducting my own personal study on how to keep your children from watching too much television and kept some notes on the effects it had on them. They are more a fan of watching different television shows and not wanting to even play with their toys. So one day I went to the store and bout some board games, activity books, coloring books, learning flash cards and even some reading books. What it is that I have found is that if I just took an hour of my time to interact with them to help get them started and interested in one of the activity’s that I have bought and got them started on one of them with me that I could leave them and do my school work, house work and even cook dinner and not one-time did I hear the words â€Å"I want to watch television Aunt Becca!† So if parents just make the time to take time out of your time just to get them interested is a tremendous outcome in the end. Obesity is one of the most dangerous side effects that are found in children that watch more television than get out and do physical activities. When children watch television after eating or while eating breakfast, snacks, lunches, and dinner are found that they don’t want to get up, stop watching television and go outside and play with friends or siblings. Now they are doing nothing to help burn off the calories that they are consuming then they run a risk at becoming obese and develop other health issues later in life. According to â€Å"How T.V. Effects Your Child† (1995-2012), â€Å"Studies have shown that decreasing the amount of TV kids watched led to less weight gain and lower body mass index (BMI — a measurement derived from someone’s weight and height)†. One of the things that can help children avoid becoming hungry while watching television is by trying to minimize the commercials, because commercials are filled with yummy foods and snacks that they like to eat. One of the things to help with that would be when there is a commercial on pull them away to do some sort of activity like, clean their room, fold cloths, or just by even having them come in and explain what it is that is going on in their television show. Monitoring what children watch on television is one of the best things that you can do to keep our children from becoming obese, violent, dependent on television, and less disruptive in school. In conclusion there are many different pros and cons of television and the effects that it has on children can go both ways, but it is up to the parents to make sure that their children get the physical activity, mental education and correct role models that they need to make sure that they live a more healthier and active life style. Because our children are the future of America and parents want to make sure that their future is going to be a bright and active life. Reference: PEDÃÅ"K, Dr. Åž. B. (2012, January). A STUDY ON CHARACTERISTISCS OF PARENTS’ TV VIEWING AND CHILDREN’S OPINIONS ON THE CARTOONS THEY WATCHED. International Journal of Business and Social Science, 3(1), 224-233. How T.V. Effects your child. (2011). Retrieved from http://www.nemours.org/content/nemours/wwwv2/patientfamily/khlibrary/articles/21720.html Willson, B. J. (2008, Spring). Media and Children’s Aggression, Fear, and Altruism. , 18(1), 87-118.

Fast Food Restaurant Description

Scene in a Fast Food Restaurant. I push through the crowds of young people hovering outside the automatic doors of Burger King, kicking the empty paper cups and bags out of my way. Stepping inside, the first thing that hits me is the sound. It crashes over me, engulfing me, drawing me in. I step closer, into the midst of it. To my left sit a young couple, anxiously feeding their toddler chicken nuggets dipped in tomato sauce. The two year old cries and whines, putting his hand up to his mouth as if to say ‘no, no more. ’ The group of young people to my right are laughing, shouting and flirting.One of the boys has stolen a girl’s milkshake and she leans across her friends, giggling happily, to try and snatch it back. I can hear the radio playing faintly. The newest, noisiest dance track struggles to be heard in the room full of people, resembling a school canteen. As I make my way upstairs I pass a smartly dressed businessman, holding a brown bag containing a burge r, and his other hand to hold his drink. He has his mobile phone trapped between his ear and his shoulder and he jabbers away to his colleague about ‘redundancies’.An elderly woman, accompanied by two young, brightly dressed grandchildren, frowns at the man as she makes her way past, children in tow. The smell of the greasy, fatty burgers is overpowering now, and I can hardly breathe for the stench if freshly cooked French fries. They coat the floor, like a three-inch carpet, soft underfoot. I wonder why these restaurants even bother installing bins – nobody seems inclined to use them. Spotting no empty tables, I make my way back downstairs to order my food. I overtake the queue if people waiting for ‘veggie-burgers’ and order large fries and a chocolate milkshake.The young girl who serves me can’t be much older than myself, yet she looks older, more tired, world-weary. Her shoulder length hair hangs limp and greasy under her baseball cap, and her red t-shirt is stained with fat and fizzy drinks. The woman next to me has dropped her tray, and someone with a mop rushes to clean up the split cola, before anyone has a chance to fall in it. I smell the air, take a French fry out of the packet, pop it in my mouth and sigh. It tastes like grease, unhealthy and fattening. Looking around me, I decide to find a bench outside and, licking my lips in anticipation of my milkshake, I go in search of one.

Biography of Alfred Nobel, Inventor of Dynamite

Biography of Alfred Nobel, Inventor of Dynamite Alfred Bernhard Nobel (October 21, 1833–December 10, 1896) was a Swedish inventor, chemist, and businessman known for inventing dynamite and establishing the Nobel Prizes in Chemistry, Physics, Physiology or Medicine, Peace, and Literature. Fast Facts: Alfred Nobel Occupation: ChemistKnown For: Inventor of dynamite; established the Nobel PrizesBorn: October 21, 1833 in Stockholm, SwedenParents: Immanuel and Karolina NobelEducation: Private teachers in St. Petersburg and lab work in Paris (no formal degree)Died: December 10, 1896 in San Remo, Italy Early Life Alfred Nobel was born October 21, 1833 in Stockholm, Sweden, one of 8 children born to Immanuel and Andriette Nobel. The same year Nobel was born, his father, a building constructor, went bankrupt due to financial misfortune and a fire that destroyed much of his work. In 1837, Immanuel left Stockholm for Russia, establishing himself in St. Petersburg as a successful mechanical engineer providing equipment for the Russian Army. Immanuel’s work included explosive mines, which would detonate when a ship hit them. These mines worked by using a small explosion to set off big ones, an insight which would be important to inventing dynamite. Immanuel’s family joined him in St. Petersburg in 1842. There, Nobel was educated by private teachers, learning the natural sciences, languages, and literature. One of Nobel’s chemistry teachers was Professor Nikolai Zinin, who first told Nobel about nitroglycerine, the explosive chemical in dynamite. Though Nobel was interested in poetry, his father wanted him to become an engineer and sent him abroad to study chemical engineering. Nobel never obtained a degree or attended a university. However, he worked in the lab of Professor Jules Pà ©louze in Paris. Mass Production of Nitroglycerine In 1847, the Italian chemist Ascanio Sobrero discovered nitroglycerine. Though the explosive power of this chemical was much greater than gunpowder’s, it was incredibly difficult to handle and could explode unpredictably. Because of this, people avoided dynamite. In 1852, Nobel came back to work in his father’s business, which was successful because it worked with the Russian Army. In 1856, however, the Crimean War ended and the army cancelled its orders, leading Nobel and his father to look for new products to sell. Nobel and his father had heard of nitroglycerine from Professor Zinin, who had shown them nitroglycerine some time at the beginning of the Crimean War. They began working on nitroglycerine together.  One idea, for example, was to use nitroglycerine to improve explosives for Immanuels mines. However, Immanuel was not able to achieve any notable improvement. Nobel, on the other hand, made significant strides with the chemical. In 1859, Immanuel was facing bankruptcy again, and returned to Sweden with his wife and another of his sons. Meanwhile, Nobel stayed in St. Petersburg with his brothers Ludvig and Robert. However, his brothers soon focused on rebuilding the family business, eventually turning it into an oil empire called The Brothers Nobel. In 1863, Nobel returned to Stockholm and continued working with nitroglycerine. One year later, he filed a patent for the blasting cap, a detonator that could be ignited by lighting a fuse. This invention revolutionized the field of explosives, and was integral to the development of modern explosives. Nobel’s new blasting technique garnered significant attention from mining companies and the state railways, which began to use it in their construction work. However, a series of explosions involving the chemical- including one which killed Nobel’s brother Emil- convinced authorities that nitroglycerine was extremely dangerous. The use of nitroglycerine was banned in Stockholm, and Nobel continued to manufacture the chemical on a barge on a lake near the city. Despite the high risk involved in using nitroglycerine, the chemical had become essential to mining and railway construction. In 1864, Nobel began the mass production of nitroglycerine in Stockholm, founding companies throughout Europe. However, several accidents with nitroglycerine led authorities to introduce regulations restricting the manufacture and transport of explosives. Invention of Dynamite Nobel continued looking for ways to make nitroglycerine safer. During his experiments, he found that combining nitroglycerine with kieselguhr (also called diatomaceous earth; mostly made of silica) formed a paste which allowed the chemical to be shaped and detonated on command. He patented this invention in 1867, calling it â€Å"dynamite† after the Greek word for power (dynamis). The demand for Nobel’s dynamite surged. Since the user could control the explosions, it had many applications in construction work, including tunnel blasting and road building. Nobel continued building companies and laboratories all over the world, amassing a fortune. He developed other explosives as well, such as blasting gelatin- which had even more explosive power- and ballistite, a smokeless gunpowder. Though dynamite was Nobel’s main business, he also worked on other products, such as synthetic leather and artificial silk. Later Life and Death At the age of 43, Nobel advertised himself in a newspaper: â€Å"Wealthy, highly educated elderly gentleman seeks lady of mature age, versed in languages, as secretary and supervisor of household.† The Austrian countess Bertha Kinsky answered the call, but two weeks later she returned to Austria to marry Count Arthur von Suttner. Nobel and Bertha continued to correspond with one another even as she became increasingly critical of the arms race and he continued to work on explosives. He may have justified his decision to Bertha with the rationale that he could create something so destructive and terrible that it would stop all wars forever. Alfred Nobel died of a stroke on December 10, 1896 in San Remo, Italy. The Nobel Prize After Nobel died in 1896, his will stated that his fortune should be used for prizes in five categories: physics, chemistry, physiology or medicine, literature, and peace. (The Nobel Memorial Prize in Economic Sciences, also known as the Nobel Prize in Economics, was established much later, in 1968.) His will was executed by two engineers, who formed the Nobel Foundation to coordinate Nobel’s finances and award the prizes. Nobel’s choices for scientific prizes may have been influenced by his background in science and invention. The founding of the peace prize may have been influenced by the peace activist Countess Bertha von Suttner, or his guilt for creating a material that was so destructive. After Nobel’s death, Bertha was awarded the 1905 Nobel Peace Prize for her work. Sources Jorpes, J. Erik. â€Å"Alfred Nobel.† British Medical Journal, 1959, pp. 1–6.Livni, Ephrat. â€Å"The Nobel Prize Was Created to Make People Forget Its Inventors Past.† Quartz, 2 Oct. 2017, qz.com/1092033/nobel-prize-2017-the-inventor-of-the-awards-alfred-nobel-didnt-want-to-be-remembered-for-his-work/.Ringertz, Nils. â€Å"Alfred Nobel - His Life and Work.† Nature Reviews - Molecular Cell Biology, vol. 2, 2001, pp. 1–4.

Concept of Steganography in Society

Concept of Steganography in Society Introduction Cheddad, Condell, Curran and Kevitt (2010) allege, â€Å"Steganography refers to the art of covered or hidden writing† (p. 752). The primary objective of steganography is surreptitious communication to conceal a message from unauthorized parties. Steganography is different from cryptography, which is an art of hidden writing that aims at ensuring that a third party does not read a message.Advertising We will write a custom research paper sample on Concept of Steganography in Society specifically for you for only $16.05 $11/page Learn More While steganography hides the presence of a secret communication, cryptography leaves it palpable. Despite numerous distinctions between steganography and cryptography, there are numerous similarities between the two. Some scholars treat steganography as a method of encryption. Nevertheless, this article will tackle steganography as a distinct way of ensuring information security. Even though the term st eganography was invented in the early 16th century, the use of secret communication dates back a couple of millennia. Before the innovation of steganography, people could tattoo messages on the scalps of slaves or hide information in the stomachs of rabbits (Cheong, Ling, Teh, 2014, p. 3566). Students and kids have been using indiscernible ink for hundreds of years. Besides, terrorists and spies have for decades used the concept of concealed communication to perpetrate serious espionages (Cheong et al., 2014).  Despite steganography hiding the hidden message, it is easy to note that two parties are communicating. The process of steganography entails inserting covered communication in a particular transport means, known as the carrier (Cheong et al., 2014). The clandestine communication is attached to the carrier to create the steganography medium. The parties may use a steganography key to encrypt the concealed message or randomize the scheme. There are two main categories of ste ganography; technical and linguistic steganography (Cheong et al., 2014). Technical steganography applies experimental techniques to conceal a communication. The experimental methods include microdots, invisible ink, and other size-reduction mechanisms. On the other hand, linguistic steganography hides a message in a transport medium in a manner that is hard to detect (Cheong et al., 2014). History of Steganography Throughout history, individuals have been concealing messages through numerous approaches and variations. For instance, in the early days, the Greeks used wax-coated tablets to hide texts. To relay a secreted message, an individual would scrap wax off a tablet, engrave a communication and conceal it using wax. It was hard for other people to suspect that a wax-coated tablet contained significant information (Chiew Pieprzyk, 2010).Advertising Looking for research paper on communications media? Let's see if we can help you! Get your first paper with 15% OFF Learn More Another ingenious method was to â€Å"shave the head of a messenger and tattoo a message or image on the messenger’s head† (Fridrich, Goljan, Hogea, 2012, p. 86). Once the hair grew back, it was hard for people to notice the message. The recipient of the message had to trim the messenger’s hair to retrieve the communication. During the World War II, people began to use invisible ink to send messages. During this period, steganography entailed the use of invisible inks only. The inks enabled people to encrypt a message in an apparently innocent letter. It was hard for a third party to detect a signal included in a message. Later, technological development made it easy for third parties to recognize concealed messages. Consequently, people had to look for alternative methods of relaying clandestine messages. The need for hiding sensitive information led to the invention of the microdot technology (Fridrich et al., 2012). The technology used i mages to send information. It made it easy for government agencies and criminal groups to relay information undetected. As computer experts continue to develop programs that can detect hidden communications, people are developing novel steganographic applications. Some information security experts have built on ancient steganographic methods. Indeed, the present development of computer technology has resulted in a revolution in steganography. People continue to store massive and sensitive information in computers and broadcast it over networks. There is no doubt that steganography has infiltrated the digital era (Hamid, Yahya, Ahmad, Al-Qershi, 2012). Today, there are steganographic applications that enable people to hide any form of a binary file in other records. Nevertheless, most messages are transmitted in the form of audio and image files. Hamid et al. (2012) hold that steganography offers some quite valuable and economically essential roles in the digital universe. For insta nce, steganography facilitates digital watermarking. Digital watermarking enables an author to â€Å"embed a hidden message in a file to safeguard the integrity of the content† (Hamid et al., 2012, p. 177). An artist, for instance, can publish their creative work on a website without fear that another person might steal it. If other parties take the work and claim it to be theirs, the real owner can retrieve the watermark to substantiate their claims. Even though both digital watermarking and steganography use similar concepts, the former has singular technical objectives.Advertising We will write a custom research paper sample on Concept of Steganography in Society specifically for you for only $16.05 $11/page Learn More The contemporary steganography allows people to conceal data in varied formats like text, images, internet protocol (IP) headers, and email. Hernandez-Castro, Blasco-Lopez, Estevez-Tapiador and Ribagorda-Garnacho (2006) claim that s teganography has been crucial in information warfare throughout history. Hernandez-Castro et al. (2006) posit, â€Å"Steganography continued to be seen as another aspect of the internet until the September 11th attack against the United States† (p. 68). A majority of the media outlets alleged that terrorists were using steganography to send secret messages. They further noted that terrorists could entrench messages into pornographic image files, websites, notice boards, and chat rooms (Hernandez-Castro et al., 2006). However, it was hard for the media outlets to substantiate their claims since they never produced evidence. Today, many people are apprehensive that terrorists may use steganography to stage a devastating cyber attack. Consequently, the internet civil libertarians call for the law enforcers to institute stringent rules to govern encryption and steganography (Hernandez-Castro et al., 2006). Principles of Steganography According to Hmood, Jalab, Kasirun, Zaidan, an d Zaidan (2010), various embedding techniques and rules enable communicating parties to conceal messages in a given medium. Nonetheless, all the techniques and regulations must meet several principles for steganography to be useful. One of the principles is that the integrity of the concealed message must not change during and after concealment. In other words, the meaning and purpose of the hidden message should remain intact. A successful steganography is one that upholds the integrity and quality of the secret information. Another principle is that the image or object used to hide information should remain unchanged (Hmood et al., 2010). People should not see changes in the stego-object as this might stir nosiness. Individuals sending messages through steganography should always presume that a third party is aware of the concealed message. Such an assumption helps to ensure that the communicating parties are cautious when concealing and relaying messages. Steganographic Technique s People use different approaches to hiding information. Over the years, information technology (IT) experts have come up with diverse techniques of embedding covert information in multimedia objects. According to Lin and Tsai (2008), IT experts have come up with multiple ways of entrenching messages in images such that it is hard to detect them.Advertising Looking for research paper on communications media? Let's see if we can help you! Get your first paper with 15% OFF Learn More The experts encode entire message or segments of a message in â€Å"noisy† regions that are hard to detect. Besides, some experts distribute a message haphazardly all over the image. The most conventional steganographic techniques used in images include â€Å"masking and filtering, least significant bit (LSB) insertion and transform techniques† (Lin Tsai, 2008, p. 407). Apart from the steganographic techniques used to conceal messages in images, individuals use numerous methods to hide messages in texts. The methods include feature, word shift, and line shift coding (Lin Tsai, 2008). Least Significant Bit Insertion Least significant bit (LSB) insertion is the most common and straightforward method of securing information. The method entails attaching a message to a cover file. The primary disadvantage of LSB is that it is susceptible to even a minor image change. Changing an image may have significant repercussions on the concealed message. The least significant bit (LSB) insertion technique uses a steganographic application that packages LSB insertion to ensure that it is hard for a third party to detect a concealed message. According to Luo (2010), the application uses EZStego tools to organize the palette and minimize the chances of arranging colors that differ so much close to one another.  The EZStego tools are used mainly in gray-scale images. The method works fine in images with associated colors. Apart from EZStego tools, LSB technique also uses the S-Tools. The S-Tools are different from the EZStego tools as the former require drastic palette changes (Luo, 2010). For the 24-bit images, altering the least significant bit of the pixels may result in new colors. The S-Tools facilitates minimization of the number of colors without affecting the quality of an image. Therefore, the S-Tools guarantee that changes in LSB do not affect the color values. Masking and Filtering Papapanagiotou, Kellinis, Marias, and Georgiadis (2007) allege that masking and filtering technique is useful in gray-scale and 24-bit images. The technique conceals messages by marking an image in a manner similar to paper watermarks (Papapanagiotou et al., 2007, p. 591). Watermarking systems are more incorporated into the picture. Therefore, the system ensures that the quality of an image is not lost due to lossy compressions. Unlike traditional steganography that hides information, the masking and filtering technique conceals messages by extending the information and assuming a characteristic of the cover image. Masking is more versatile than the least significant bit (LSB) insertion in terms of cropping, image processing, and compression. The masking and filtering technique entrenches information in crucial areas such that the concealed communication is more important to the cover image than just hiding it in the noise areas. Transform Techniques The transform techniques embed the message by modulating coefficients in transform domain like discr ete cosine transform (DCT) used in Joint Photographic Experts Group (JPEG)† (Qiao, Retraint, Cogranne, Zitzmann, 2015, p. 15). The transform techniques help to retain the quality of an image after lossy compression or image processing. One of the transform techniques that are common in information security is Jpeg-Jsteg. Qiao et al. (2015) argue that Jpeg-Jsteg â€Å"creates a JPEG stego-image from the input of a message to be hidden and lossless cover image† (p. 18). The autonomous JPEG group holds that the existing Joint Photographic Experts Group’s (JPEG’s) software has been altered to work with 1-bit steganography in JPEG File Interchange Format (JFIF) output files. The files comprise lossy and nonlossy segments. The software uses a JPEG algorithm to coalesce the concealing images and message leading to the formation of JPEG stego-images. The DCT helps to compress the JPEG images. Apart from the discrete cosine transform, the communicating parties can use Wavelet Transform and Discrete Fourier Transform to process images (Qiao et al., 2015). The techniques change other features of an image like brightness. The hidden information is distributed throughout the cover image using patchwork and other techniques.  Wang, Wu, Tsai, and Hwang (2008) allege â€Å"Patchwork uses redundant pattern encoding or spread spectrum methods to scatter hidden information throughout the cover images† (p. 154). These methods help to maintain the security of the hidden message during image transformation process like rotation or cropping. Besides, they conceal a message more comprehensively than through simple masking. Other transform techniques encrypt and distribute the hidden data all over an image. Distributing the secret information makes it look like noise. Hence, it is hard for a third party to detect the message. Such techniques use a stego-key to secure information. Consequently, even if a third party manages to extract some bits of a concealed message, they can hardly decipher it without the stego-key and the algorithm. A good example of this steganographic technique is the White Noise Storm technique (Wang et al., 2008). The method relies on frequency hopping and distribution range technology that spreads the data all through the image. Despite the ongoing developments in information security, steganography cannot substitute for cryptography. Instead, it ought to work as an addition to encryption (Wang et al., 2008). Line Shift Coding Line shift coding technique entails moving various lines inside the document up or down by a small fraction according to the codebook (Liu Tsai, 2007, p. 27). The affected lines are hard to detect since the alteration is too diminutive. However, one can identify the lines using a computer by measuring the gaps between individual lines. Line shift coding uses differential encoding techniques to hide information. The method ensures that the lines bordering the one being shifted re main untouched. The direction of the change is used to represent a single bit. When an entire document is put together, it is easy to entrench multiple bits, and thus be in a position to conceal a large data. Word Shift Coding According to Shirali-Shahreza and Shirali-Shahreza (2006), the principles of word shift coding technique are similar to those of the line shift coding. However, for the word shift procedure, the words are moved instead of lines. Additionally, the words are moved to the left or right but not up or down. The word shift technique is also referred to as the justification of the document. The codebook instructs the encoder on the words to move as well as the direction of the movement. Again, the moved words are identified by measuring the gaps between individual words. Both the right and left shifts are assigned different bits. Feature Coding Feature coding technique is slightly different from word shift and line shift coding skills. The feature coding method uses a parser to evaluate a document. The parser generates a unique codebook for individual documents. Satir and Isik (2012) claim that the parser selects all the characteristics that it deems might help to conceal a message. Feature coding technique uses different features to enforce security (Satir Isik, 2012). They include the dots on top of individual letters like i and j and the height of certain letters. Besides, feature coding technique may be used together with line shift and word shift techniques to enhance security and augment the quantity of information that can be concealed. Benefits of Steganography The main advantage of steganography is that it is easy to relay a message clandestinely without the knowledge of a third party. Steganography allows parties to a communication to hide different types of files over any communication medium in a way that it is hard for unauthorized persons to detect or read the concealed data. Such capabilities have numerous effects, both positive and negative, on the contemporary world. For instance, people can use steganography to relay sensitive and confidential information, therefore safeguarding their privacy (Castiglione, De Santis, Soriente, 2007). Additionally, an organization may use steganography to preserve copyrighted property. The present level of competition in the corporate world calls for the protection of business strategies. For an organization that uses the internet to communicate with employees, it might be hard to secure information from unauthorized persons. Nevertheless, the use of steganography can go a long way towards ensuring that employees share organizational policies in a safe manner. Sumathi, Santanam and Umamaheswari (2014) claim that steganography can facilitate information warfare. A government may use steganography to relay sensitive information without the knowledge of the enemies in the event of a war. For instance, government spies may use steganography to inform their soldiers about th e strategies that an enemy intends to use, therefore facilitating preemptive attacks. Limitations of Steganography Steganography has numerous limitations. One of the limitations is that the process involves momentous overhead to conceal a limited amount of data. One requires a lengthy text to hide a short text message (Rengarajan, Jiaohua, Balaguru, 2012). Besides, it is hard to hide audio or image files in text records because of their sizes. The size of the medium used to conceal a message is a major limitation. The principles of steganography dictate that a message must be hidden without changing the integrity of the medium used to protect the communication (Rengarajan et al., 2012). However, it is hard to conceal data without affecting the quality or nature of the concealing object. Another limitation of steganography is that it is prone to attacks (Rengarajan et al., 2012). Once hackers detect a steganographic system, it becomes ineffective. Consequently, steganography does no t guarantee the security of a message that is in transit. Thus, it is difficult for institutions or government agencies to transmit sensitive or classified information through steganography. Rengarajan et al. (2012) allege that steganography acts as a suitable avenue for terrorists to perpetrate heinous acts or spread propaganda. The dynamic nature of the contemporary electronic networks makes it easy for terrorists to send messages without being detected. Today, people create new websites and discard them after use (Saha Sharma, 2011). Besides, novel auctions are mushrooming on a daily basis. All these offer tremendous opportunities for terrorists to create steganographic contents. According to Saha and Sharma (2011), a majority of the steganography detection mechanisms are numerical. They focus on the files that look suspicious. Thus, the terrorists take advantage of this loophole to perpetuate crimes. The fact that paintings, photographs, graphics, and drawings have varied image features makes it hard for the existing detection techniques to identify the files that look suspicious (Sallee, 2005). Besides, criminals have identified new methods of circumventing detection. Today, criminals use distraction or diversion techniques to evade detection (Saha Sharma, 2011). The methods entail adding inconsequential data inside a single file. The inconsequential data serves numerous purposes. The criminals ensure that the data corresponds to a particular statistical profile. Thus, when a file is scrutinized, the detection software detects the insignificant data. Hence, the authorities do not discover the actual message. Conclusion Institutions and government agencies have been using steganography to relay classified information for security purposes. The growth in technology and the advent of the internet have resulted in tremendous changes in steganography. People no longer use steganography to send classified and concealed messages only. Presently, numerous stega nographic tools are accessible to the public. As long as people have access to the internet, they can use the available steganographic tools. Unlike in the past where people concealed information in the bellies of animals or tattooed it on scalps, technology has made it easy to embed a message in a text, image or even an audio file. Indeed, people can transmit concealed data over a long distance without fearing that it might fall into the wrong hands. The growth of steganography has not come without merits and demerits. It has enabled people and organizations to safeguard copyrighted properties. Furthermore, government agencies can relay classified information without being detected. The major drawback of steganography is that terrorists can use it to communicate and spread propaganda. The growth of technology has opened room for criminals to come up with diversion and distraction mechanisms. Therefore, they can evade the detection mechanisms that are put in place with ease. The pub lic should know that steganography is not the safest method of sending confidential information. Rather than relying on steganography alone, people should use it together with other security techniques like cryptography. References Castiglione, A., De Santis, A., Soriente, C. (2007). 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