ABSTRACT
Voice over IP is a communication service which uses packet based networks in order to communicate among internet users. This service has provided substitute of mobile telephony by implementing low cost communication services. In this research work, we have provided a brief introduction of architecture and implementation of VoIP. A cost and benefit analysis of this service is also explained and on the basis of this analysis, we have proposed the use of VoIP as beneficial as compared to other communication ways using mobile networks. A discussion on implementation of VoIP in different organizations will also be discussed in this document.
INTRODUCTION
Voice over Internet Protocol (VoIP) is the replacement of circuit switched networks or mobile telephony and provides voice transmission on internet protocols using packet switched networks. Internet telephony is replacing mobile telephony by introducing high speed packet switched networks and it is used to send voice, text and videos over the internet. VoIP is applied in three forms today in Phone to computer, computer to computer and phone to phone voice transmission over the internet. All voice analog signals are sent to internet by dividing into packets. In the past few years, packet switched networks were considered unreliable and cause delay in sending voice packets. Delay in voice packets cannot be sustained, therefore circuit switched networks had priority in sending voice transmission. Soft switch is capable of merging mobile networks and packet based networks by reducing the delay time for voice transmission and as a result, VoIP is possible using a soft switch as the central entity of communication networks.
Reliability of VoIP networks is considered less as compared to circuit switched networks because in public switched telephone networks (PSTN), a dedicated line is allotted to a used while communication is taking place. On the other hand, VoIP is based on the transmission of voice in the form of packets and reliability of the complete traversing of data to the destination is at a risk. Best effort protocols try to provide maximum quality of service to the user, but still there can be problems of lateness and data loss. On the basis of reliability and delay, appropriate protocol and priority algorithm can be used for VoIP networks. For voice and video transmission, delay is not bearable. So quality of service is to minimize delay at the cost of data loss. While on the other hand, reliability for crucial data is ensured by providing successful data transmission at the cost of delay in transmission.
This research paper will explain the introduction and working of VoIP and will demonstrate the usage of VoIP in public and private organizations as well as its usage in healthcare, military, education and business. A comparison of cost and benefit analysis of VoIP technology will also be discussed.
RESEARCH PROBLEM
Voice over IP is a common technology used today to deal voice transmission over the internet using broadband networks and DSL lines. Different organizations are utilizing VoIP for according to their requirements based on the quality of service for voice transmission. VoIP has significantly replaced the public switched telephone networks (PSTN), or circuit switched networks by providing the similar services over internet. VoIP providers have claimed that VoIP has significantly reduced the cost required for voice transmission worldwide. This research paper will perform a cost and benefit analysis for VoIP and will analyze the usage of VoIP as compared to other mobile networks. A discussion on the usage of VoIP in public and private organizations will also be discussed in this research work.
LITERATURE REVIEW
(Black, 1999) has a detailed discussion on VoIP technology. The author has explained the requirement, architecture and implementation issues of VoIP technology. Challenges and issues of VoIP as compared to circuit switched networks is also discussed. This book does not cover the implementation of VoIP applications in different organizations and industry fields.
(Upkar, et al , 2002) presents a cost and benefit analysis of VoIP technology with functionalities and extensive services of VoIP in current networks. A brief discussion of the architecture of VoIP is also discussed. This paper also presents a comparison of VoIP with circuit switched telephone networks.
In (Chong, Hui Min, and Matthews, 2004), the authors discussed the implementation issues of VoIP technology. All types of costs that affect the utilization of VoIP are also explained, including implementation, running and maintenance cost. Results are taken by implementing on different number of real time users.
In (Cole, Robert G, and Rosenbluth, 2004), the authors have proposed to place monitors in the Gateways and Transport paths and have compared the results. By placing monitors in transport path, the delay or jitter can be affected.
BRIEF ARCHITECTURE OF VOIP
Voice over IP is an internet protocol based architecture which is used to communicate voice over internet. VoIP provides the similar types of services as provided by circuit switched networks with less bandwidth utilization and using the built architecture for internet services.
In order to communicate voice data over internet, analog to digital conversion of voice data is required at first step. This step is performed by using Sampling, Quantization and Encoding workflow. At the receiver, this step is reversed in order to get analog voice from digital data received.
Basic components of a VoIP architecture include Networks supported end node, Gateway, Gatekeeper and a Control Unit. Gateway performs the services of routing, channel allocation and signaling while Gatekeeper provides address allocation services. Control Unit deals with broadcast communication and End Node is responsible for internet connectivity and computer application for communication. VoIP uses H-323 protocol for implementing multimedia applications in a distributed architecture. Other protocols used by VoIP include SIP, MGCP, RTP, H-248 and SDP.
Common applications of VoIP are web based voice applications like Skype, Viber, Google Talk and many others. These applications are widely used by mobile users and other network users on the internet.
COST AND BENEFIT ANALYSIS
VoIP According to developers, VoIP has reduced cost of voice communication significantly using bandwidth efficiency and current technology. Moreover, the cost in terms of a dedicated channel allocation for each user is also reduced by utilizing idle slots within the communication.
Long distance call charges on mobile telephony are significantly expensive as compared to VoIP. Only cost required for VoIP is internet service charges. This service of internet based communication has provided the functionality of connecting people anywhere with the requirement of internet connection only.
VoIP technology is widely used in healthcare for telemedicine and tele-health services by replacing the communication with traditional networks. This step has reduced huge amount of expenses of Meaningful Use (MU), a startup initiated by American government to utilize Information Technology in Healthcare services.
On the other hand, providing high speed internet cost for using VoIP services can also be considered into cost of implementation of VoIP. Evolution of third generation and fourth generation telecom networks (3G and 4G) with WiMAX and LTE networks provide the requirement of VoIP. Transition from 2G networks to these high standard networks require significantly higher cost. Circuit switched networks does not required such type of modifications. Maintenance cost of internet service providers (ISPs) also adds to the cost of VoIP implementation.
Comparing the above costs required for VoIP and circuit switched networks or mobile telephony networks, we found VoIP as the best solution for providing communication services. It is the requirement of mobile telephone networks to upgrade themselves over 3G and 4G networks, therefore the cost of implementing or upgrading these networks becomes insignificant for utilizing VoIP. We see the future of voice communication in VoIP because it provides a better solution at low cost and extra functionality.
IMPLEMENTATION IN ORGANIZATIONS
VoIP technology is widely used in different organizations of different scope and services. Avaya is using VoIP in order to provide similar type of architecture and services as mobile telephony or PSTN. For that purpose, internet based telephones are used which are connected worldwide using VoIP.
Most organizations today have utilized VoIP for office communication where office telephones are connected with internet and communication among employees is done through VoIP. This reduces the cost of communication up to much extent.
CONCLUSION
VoIP is an emerging technology used for voice communication for past few years using internet protocols and internet services. This technology is replacement of mobile telephony on PSTN and provides a similar type of services with little quality differences at quite low cost. This research work has analyzed the architecture and working of VoIP technology for communication worldwide. Cost and benefit analysis of VoIP revealed that this technology is quite beneficial in terms of cost at the expense of call quality. The call quality of internet services is not as good as compared to mobile based voice communication, but it can be sustained at quite less cost. Long distance calls on VoIP care comparatively much cost effective. This research work has also discussed organizations currently implementing VoIP technology for providing communication services to the users.
REFERENCES:
Black, Uyless. Voice over IP. Prentice-Hall, Inc., 1999.
Cole, Robert G., and Joshua H. Rosenbluth. "Voice over IP performance monitoring." ACM SIGCOMM Computer Communication Review 31.2 (2001): 9-24.
Chong, Hui Min, and H. Scott Matthews. "Comparative analysis of traditional telephone and voice-over-Internet protocol (VoIP) systems." Electronics and the Environment, 2004. Conference Record. 2004 IEEE International Symposium on. IEEE, 2004.
Varshney, Upkar, et al. "Voice over IP." Communications of the ACM 45.1 (2002): 89-96.
