Opportunities, Quality of Service and Risks/Threats of VoIP - Research Proposal Example

Research Proposal: Opportunities, Quality of Service and Risks/Threats of VoIP Table of Contents I. Introduction II. Research Question III. Objectives IV. Literature Review IV.i. VoIP IV.ii. Opportunities IV.iii. Quality of Service (QoS) IV.iv. Security-Risks/Threats IV.v. VoIP Tools (Hardware and Software) V. Methodology VI. Timescale and Resources VII. Summary VIII. Reference I. Introduction Technological innovations provide many more useful product and services which can improve the way of life. VoIP is the name of new technology which is used for communication purpose. VoIP stands for voice over Internet Protocol; it uses the same protocols that Internet uses. So it can be said that voice over Internet Protocols means voice that travels by the same protocols used on the Internet. It is also called as IP telephony. The reason for this is that it uses Internet Protocols to make voice communication. The Internet Protocols are the basis of IP networking. It supports corporate, private, public, cable, and even wireless networks. Every technology comes with impartial risks. The same case can be applied with VoIP. The business of securing data is becoming more important and relevant each day. There are several instances when critical business systems are compromised regularly and used by unauthorized persons for illegal use. Some of the recent instances are; Seisint (Lexis-Nexis research), Choicepoint, Bank of America, PayMaxx Inc, and DSW Shoe Warehouses. Seisint, which has information about 310,000 people, was hacked. The information mainly consists of names, addresses, and social security number. Choicepoint allowed criminals to buy the private identity and credit information of more than150,000 customer accounts. Bank of America announced that it had “lost” tapes containing information on over 1.2 million federal employee credit cards. PayMaxx Inc. suffered a security lapse that may have exposed financial data on as many as 100,000 workers. DSW Shoe Warehouses revealed that credit card data from about 100 of its stores had been stolen from a company computer over (Porter et al. 2006). Although these are the cases related to data network or it can be said to relate to internet. But all the above cases can be considered too for VoIP, as it uses the same protocol as used by the internet. Also various threats that are related to internet will be applicable for VoIP network too. Some of the common threats are virus, Trojan horse, worm, denial of service attack or VoIP service Disruption, call hijacking and interception, ARP Spoofing, H.323-Specific attacks, and SIP-Specific attacks. All the parameters and security that are involved and used by data network and internet can be applicable for VoIP also. One major concern that is said for the VoIP is the quality of services that it provides. Now with the use of broadband connections by home users and dedicated lines used by the many organizations, this concern can be reduced very much. There are several benefits of VoIP that is why it is a hot topic in these days. Many organizations are now using VoIP for their communications purpose. The first benefits that VoIP provides is the lower costs of operations as organizations can use their existing network for communication. Another benefit is associated with the regional toll charges, which will be not applicable in case of VoIP for that current POTS charges an extra bill for providing these services. Also VoIP is less expensive from the point of view of management and maintenance. Initial investment and implementation for VoIP is expensive but it can be repaid as VoIP have lower operating and maintenance cost. Also with the use of VoIP in existing networks it will be easier to monitor single network for both data and communication (voice) purpose. This research proposal aims to study the significance of the quality of service (QoS), opportunities and benefits and various types of risks and threats that are concerns for VoIP. The first section of the paper covers research question and objectives, followed by literature review and methodology. This is followed by the timescale and resources which would be required for the study. II. Research Question The research question of the study is as follows: What are opportunities, quality of service (QoS) and risks/threats (security) associated with VoIP? III. Objectives The objective of the study is To understand what actually is VoIP and how it is different from POTS (plain old telephone systems). To find out various types of VoIP that exists and has been adopted by the organizations and persons. To find out the opportunities in VoIP. To find out the level of Quality of Service associated with VoIP. To understand various types of risk and threats that can impact the services of VoIP As stated earlier, VoIP means for voice over Internet Protocols. The main difference between VoIP and POTS is that VoIP uses packet switching and POTS uses circuit switching. Any IP-enabled device such as an IP telephone, a computer, or even a personal digital assistant (PDA) can be used for communication purpose with the use of VoIP technologies. Although it said as new technology but it have presence more than a decade. Many organizations and persons use this. Some of the organizations which provide VoIP services with the use of messenger are Skypee and Yahoo. One can use this messenger and can communicate to computer or telephone with a very little nominal cost. As VoIP uses existing network that is used by organizations and individuals, therefore running and operating cost for VoIP is far less as compared to POTS. The quality of service of VoIP depends upon bandwidth of the network used. By employing dedicated network for the VoIP, the quality of service of VoIP will match with the existing telephone communications. There is also many risk and threat associated with the VoIP. As VoIP uses Internet protocols, therefore all the security risk that is applicable for Internet is applicable for VoIP. The next section will give details on all the objectives that are stated here. IV. Literature Review Before starting this section lets looks some term and their definitions, which is given below. Internet: A collection of packet-switched network connected via routers. Protocol: A set of rules governing the exchange of data between two entities. Internet Protocol: An internetworking protocol that provides connectionless service across multiple switching networks. Local Area Network (LAN): A general-purpose local network that can serve a variety of devices. Typically used for terminals, microcomputers, and minicomputers. Wide Area Network (WAN): A WAN consists of a number of interconnected switching nodes. Packet: A group of bits that includes data plus source and destination addresses. It is generally refers to a network layer (layer 3) protocols. Packet Switching: A method of transmitting messages through a communications network, in which long messages are sub divided into short packets. The packets are then transmitted as in message switching. Usually packet switching is more efficient and rapid than message switching. Circuit Switching: It is method of communication in which a dedicated communication path is established between two devices through one or more intermediate switching nodes. Unlike packet switching, digital data are sent as a continuous stream of bits. Bandwidth is guaranteed, and delay is essentially limited to propagation time. The telephone system uses circuit switching. Router: A device used to link two or more networks. The router makes use of an internet protocol, which is connection protocol. Wireless: refers to transmission through air, vacuum, or water by means of an antenna. (Stallings 2004) IV.i. VoIP VoIP is the technology by which voice communication as made by telephone can be made possible. With the use of VoIP any computer or telephone connected to the internet with a broadband connection can call another computer or phone. This can be done at a fraction of minimal cost, or absolutely free. Figure 1: VoIP Communication VoIP stands for Voice over Internet Protocol. VoIP Phone or some time referred as IP telephone or broadband phone is a voice communication service which uses high-speed broadband connection. Two types of VoIP phones services exist; phone based and computer based. Both the VoIP services allow its user to make voice communication (phone calls) by either using regular phone (cellular and landline) or a computer headset with a microphone, respectively. In the case of VoIP, as opposed to a traditional landline, a call is sent over the Internet instead of over copper wires. VoIP uses Internet protocol (IP) for making voice communication. VoIP uses packet switching as opposed to circuit switching used by traditional phones. The voice stream (data) is broken into packets which also contains the destination address, compressed and sent over internet. At the other end where call is to be supposed to make these packets are reassembled, decompressed and is converted back to a voice stream by the use of various hardware and software. It is all dependent upon the nature of call made and its final destination where call is made. This process is vice-versa and by this the voice communication between two users is made. According to Porter et al. (2006), VoIP technology enables traditional telephony services to operate over computer networks using packet-switched protocols. Packet-switched VoIP puts voice signals into packets along with the voice signals. It includes both the caller’s and the receiver’s network addresses. VoIP packets can traverse any VoIP compatible network. Because VoIP uses packets, much more information can be carried over the network to support and enhance user’s communication needs compared to traditional telephony methods. In a circuit-switched network such as POTS, routing is less dynamic than with a packet-switched network and if a line is down, the call can’t go through. But in case of a packet-switched network, multiple routes can be established, and packets can travel any of the available routes. If one of the lines supporting the network is down, the packet can switch to another working route to keep the call up. With VoIP, voice signals can travel the same packet-switched network infra-structure that companies already use for their computer data. (Porter et al. 2006) IV.ii. Opportunities The main benefit that VoIP provide is lower cost or sometime this is almost absolutely free of cost. With the help of VoIP phones cost of making calls can be saved as much as around 90% to the present existing phone bills. VoIP also provides many features such as voicemail, caller ID, three-way calling, and call waiting for which service provider can charge its users. Also many VoIP service providers these days offer unlimited long-distance calls with their plans, which save customers the trouble of having to purchase long-distance phone cards. In addition, they also provide options for calling in same service subscribers as long as one wish at no additional cost. Some of the main benefits that VoIP provides its users are: Lower cost User can use his phone anywhere User can make long distance call to anywhere User can bypass the taxes applicable for making calls (toll tax, service tax, etc.). Monopoly of the phones companies can be avoided. According to Porter et al. (2006), VoIP telephony services are interoperable, meaning that they work well over all kinds of networks. They are also highly portable, which means they will work with any IP-enabled device such as an IP telephone, a computer, or even a personal digital assistant (PDA). (Porter et al. 2006) According to Brown & Waring (2006), “One of the key advantages is local long distance -- by using a virtual phone number with a different area code, you can maintain a phone number in D.C. even if you live in L.A., so you won't pay toll charges when calling D.C., nor will your D.C. friends pay extra when they call you. This can be a big money-saver for business travelers and telecommuters. And thanks to new portability laws, you can keep your existing phone number when switching to VoIP if you like.” Other benefit that VoIP provides is the location independent or true portability. When a user who uses VoIP, change his/her house, can take his/her your VoIP phone adapter, plug it into the broadband connection at his/her new home, and continue calling without interruption. User should notify his/her VoIP service provider of address change, for billing and E911 purposes, but there will be no interruption of service or change to his/her phone number. (Brown & Waring 2006) According to Porter et al. (2006), the corporate world did not consider adopting VoIP in a big way until 2001. Issues pertaining to quality and security complicated VoIP’s adoption. These issues have been largely addressed, and the corporate sector is rapidly adopting VoIP. To implement VoIP, consumers require broadband access to the Internet. Broadband Internet access for VoIP is an artifact of only consumer implementation of VoIP. It is often not a consideration in corporate VoIP, which most often relies on dedicated lines that provide no Internet access. Below is the some enhanced calling features made possible by IP telephony: Vemail: Before IP telephony and VoIP, consumer accessed voice mail through a telephone and accessed e-mail through a computer. But with VoIP implementation (use), they can read their voice mail on computer screen and listen to e-mail through an IP-enabled telephone. Web-Surfing: VoIP makes possible to access the Web with an IP-enabled telephone. An IP telephone with a large enough screen can display Web pages. (Porter et al. 2006) IV.iii. Quality of Service (QoS) According to Smith (206), for efficient working, VoIP requires a high-speed Internet connection. Skype (VoIP service) Sound quality is good, but depending on the quality and speed of the Internet connection there can be a slight delay (perhaps 0.2 seconds) in the conversation “VOIP has improved and become more user-friendly, to the point where "ordinary" computer users rather than just the early adopters are installing and using VOIP software.”(Smith 2006) At present day quality of VoIP voice communication has dramatically improved over the past few years. Now quality of VoIP voice communication is reaching the quality level of a landline phone and sometimes even exceeding that level. However, VoIP voice clarity may differ from provider to provider. Quality of VoIP voice will also depend upon the speed and quality of broadband connection used for making communication. There is one drawback of service reliability for VoIP that it will not work in case of power outage or in case of a broadband service outage. So for emergency purpose user have to use cell phones or landline phones. Other problem is associated with the bandwidth that is required for VoIP voice communication. Usually most VoIP services use 50 to 100Kbps of bandwidth for both downstream and upstream. Sometime there is problem associated with IP packets that are lost or delayed at any point in the network between VoIP users; there will be a momentary drop-out of voice. This can be seen in case of highly congested networks and where there is a long distance. But as the VoIP technology improve (already) the reliability and voice quality will improve. Another problem associated with the VoIP is that it is dependent upon another separate service which is Internet connection. Therefore, the quality and overall reliability of the phone connection is entirely reliant upon the quality, reliability, and speed of the Internet connection which it is using. Any shortcomings with Internet connections and Internet Service Providers (ISPs) can affect VoIP calls and also higher overall network latencies can lead to significantly reduced call quality and cause certain problems such as echoing. VoIP also faces problem of latency and jitter, the main reason for this problem is that UDP does not provide a mechanism to ensure that the data packets are delivered in sequential order; hence quality of service is affected. Another drawback is related to make emergency call because of nature of Internet protocols makes it difficult to geographically locate network users (Wikipedia 2006). The main problems that can affect the quality of service are summarized below: Delay/Network latency Packet loss during transmission Jitter Echo Emergency calls According to Porter (2006), the factors that affect the quality of data transmission are different from those affecting the quality of voice transmission. Data generally is not affected by small delays but the quality of voice transmissions, is lowered by relatively small amount of delay. The three main factors that affect the quality of service are latency, jitter and packet loss. According to Kelly (2005), VoIP telephony service using DSL is said to be near toll quality (POTS). Kelly also states that with a private, dedicated approach to VoIP, any company/organization can achieve toll quality (or better) VoIP service. In addition, VoIP hardware and software is improving to the point where error rates will soon be a thing of the past on all network types. According to Kelly (205), the three factors that can affect quality of service (QoS) on a VoIP call are network delay, poor compression and signal attenuation. Initially, in 1995 the delay was ranged from 400 to 4000 milliseconds (4/10 to 4 seconds). Now this problem is solved because of network, which is very much improved today. In addition, VoIP compresses voice and other information into packets of data to transmit it over the network and there should be proper technique used by VoIP to compress and decompress the voice data. Also as packets travels over network there is a possibility of signal attenuations over distance and time. IV.iv. Security-Risks/Threats The computer and information technology age have changed the ways people have been doing their business and leading their lives. The growth in the use of internet and computer systems has increased the other concerns related to it. The security issues related to the data theft has increased from last few years and this has lead to the growth of various security related research and developments. The computers from one place to another are connected together with the networking. Within any network there are number of areas where threats to the security are involved. Broadly these threats can be categories on the basis of actions taken for them. These three types of actions are as follows: Prevention: This action is taken prior to any problem by understanding the possible threat to the security. These are the measures that has been taken or carried out in order to prevent damage to assets and data. The password, secret questions, definition of rights to use the system to modify, change, update or use the data etc are some preventive measures. Detection: Detection is the second level of actions taken for the security related issues. The detection measures are taken or carried out to detect the reasons of damage. This includes the issues like how, when and by whom the assets can be damaged. Reaction: Reactions are the measures taken or carried out in order to cover the damage, minimize the damage or recover any asset from the damage. A network is considered to be secured when it provides protection of integrity, availability & confidentiality of network asset and services from associated threat and vulnerabilities. Various issues covered in the network security are Confidentiality, Integrity, Availability, Authentication, Reliability, Safety and Non Repudiation. Any network security tool, device or technology is always tested on the above mentioned parameters. Confidentiality prevents unauthorized users for accessing the information they are not authorize. Integrity means any particular message should be in a particular form. The availability of information ensures that information is available at the right time, in the right place and to the right person. Authentication ensures that information is not being used by any unauthorized person or part. The above paragraph is related with the network security. Since VoIP uses Internet protocols, therefore all the security related things that are applicable for network security will be applicable for VoIP communication too. The various threats that can affect the VoIP service are voice spam, phishing, toll fraud, virus, Trojan horse, worm, denial of service attack or VoIP service Disruption, call hijacking and interception, ARP Spoofing, H.323-Specific attacks, and SIP-Specific attacks. Also the majority of consumer VoIP solutions do not support encryption yet. As a result, it is relatively easy to eavesdrop on VoIP calls and even change their content. According to Porter et al. (2006), confidentiality of voice conservations is also security issues voiced by organizations implementing VoIP. Voice traffic on VoIP network can be tapped and vulnerable to interception with the techniques used to sniff other traffic on a LAN or WAN. Even an unsophisticated attacker can intercept and decode voice conversations. Also Denial of Service (DoS) attacks, whether they are intentional or unintended, are the most difficult VoIP-related threat to defend against. Amplitude Research (www.amplituderesearch.com) reported in 2005 that: Companies had their share of network security problems. Virus and worm attacks led the list of intrusions as 63 percent of companies reported that they’ve had such problems. Trojan attacks occurred at58 percent of companies. Backdoor viruses hit 45 percent of companies, while 35 percent say they suffered attacks from viruses or worms that were introduced internally. “In a world in which the total of human knowledge is doubling every 10 years, our security can rest only on our ability to learn.”—Nathaniel Brandon. VoIP networks inherit all the security weaknesses of the IP protocol such as spoofing, sniffing, denial of service attacks, replay attacks, and message integrity attacks. All the legacy application servers that serve as adjuncts in converged networks (DNS, SNMP, TFTP, etc.) will also be targets of attack as they have been on data networks. and worms will become a real threat to the entire telecommunication infrastructure. Hacking will converge as well. (Porter et al. 2006) V. Methodology The data requirements for this study will include data from primary and secondary sources. The secondary data will include data from the secondary sources like government, the organisations which provide and use VoIP and other sources. These data will be compiled together for the analysis. Secondary Data Collection The secondary data will be collected from the government organisations and agencies which offer VoIP services and products. As stated on the BSI website “BSI British Standards is the National Standards Body of the UK and develops standards and standardization solutions to meet the needs of business and society”. The study will be based on secondary resources which includes books, journals and reports of various governmental and non government agencies. These materials can range from the subjects and topics like quality standards, security, wireless communication, networking, internet risks, threats and attacks and many more other resources that relate to VoIP technology. The data and reports from various organizations which are involved in VoIP manufacturing will be also taken in accounts. Some of the main organizations involved in VoIP are Avaya, Cisco systems, Siemens, Alcatel, Nortel, Mitel, Shortel, and Inter-Tel. Also data and reports from some of the main VoIP carrier providers such as Verizon Communication, SBC Communication, Sprint, Bellsouth, Comcast, Quest Communication and Nextel Communication will be also taken for the study. Apart from these online resources and news of various news agencies will be included in the studies. Primary Data Collection: The primary data will be collected by a survey conducted in the organizations which are using VoIP services for their organization. This will be done with the help of structured questionnaire. The questionnaire will include questions like efforts that have been taken in order to improve the quality of VoIP services, major area of concerns for the VoIP uses, training and education provided to the employees so that they can better use VoIP services securely, types of equipment they are using, differences in terms of quality of service (voice and delays) they are facing with the use of VoIP and various others. The respondent will be from various level of the organisation who uses VoIP technology for communication purpose in their network or outside network. The effort will be to include as many organisations from different sector such as agriculture, manufacturing, construction, retail, service sector and other organisations. It will be taken care of that the organization contacted will be the companies which have been listed for some or other quality standards. The questionnaire will be filled up by the employees from various level of the organisation including the organisation head. Survey will also include various other types of user (mainly home users using VoIP on their broadband connection) who uses VoIP for their communication purpose The data collected will be complied together and analysed with simple data analysis tools like Microsoft Excel or SPSS. VI. Timescale and Resources The time available for the study is from July 2007 to April 2008. Phase 1 In this phase the required material, information regarding various sources and the strategy for the rest of research will be solidified. This will be the preparation phase for the rest of the study. Phase 2 In this phase the secondary data will be collected from the various sources. The companies to be targeted for the primary research will be decided and list of the company will be prepared. The questionnaire will be prepared in this phase based on the study of secondary sources, available literature and previous work in the same area. This questionnaire will be used for the primary research. The questionnaire will cover the sections which will aim to study various aspects of quality of service (QoS) and security management in the organisation as well as the objectives for which these quality of services (QoS) and security management initiatives has been taken. Phase 3 In this phase primary data will be collected. This phase requires more time, energy and resources. This will include contacting people from various organisations, which are using VoIP or involved in providing these services to users or organizations. . Phase 4 In the phase 4 all the data will be compiled together, compared and analysed. Phase 5 All the research reports and presentation of the study will be completed in this phase of study. Time Phase 1 Phase 2 Phase 3 Phase 4 Phase 5 July 2007 August 2007 September 2007 October 2007 November 2007 December 2007 January 2008 February 2008 March 2008 April 2008 Table: Time scale for Research VII. Summary The research will entirely focus on the opportunities, Quality of Service and Risks/Threats in context of VoIP. In this research, I will include some primary research for quality of service and security perspective. This will done by analyzing questionnaire and study based on the certain organization which are using (or implemented) and involve in implementing this services. I had noticed that there are not many literatures available, which talks about QoS. This gap will be covered by my research. I will also focus on various types of risks/threats that should be considered before implementing VoIP for the communication purpose in any organization. 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