ABSTRACT
In a developing economy like Nigeria financial resources are scarce commodity. Hence, cheaper means of accomplishing tasks even within the presence of scarce resources are always explored.
This paper presents the design and implementation of a software intercom on local area network (LAN). The design provides a solution that eliminates the use of expensive hard-wired intercoms and Private Automatic Branch Exchange (PABX) by making use of only LAN and full multimedia computer allowing network users the opportunity to still communicate audibly despite the meager resources.
The design enables the use of LAN that is mostly dedicated to data traffic only to be used as a cheaper means of communication using voice and video media, presented in real-time between peers by the use of software.
The software intercom designed provided network users with cost effective, easy and reliable multimedia communication over LAN, in essence giving the users a truly multimedia experience.
Keywords: Software; Intercom; Multimedia; Communication; LAN
INTRODUCTION
The need for information at the press of a button particularly in a developing economy cannot be overemphasized since telecommunication has long become the backbone in the day-to-day running of most businesses and organizations. Hence, the need to finding new solutions to make it cheap and affordable must be sought.
Currently, digital technology is the backbone of the entire information industry. As part of this, the transformation of audio information into digital signals is now a routine process that is incorporated into our telephone, digital networks, televisions and music equipments.
Voice communication traditionally has been carried over dedicated Telephone networks operated by Telecommunication service providers such as the Nigerian Telecommunications Limited (NITEL), Globacom Nigeria Limited (GLO-MOBILE), etc in Nigeria. These telephone networks have progressively evolved from the initial analog circuits to the current digital networks with bandwidth in excess of 1 Gbps. For reasons of varying bandwidth and networking requirements, different services are provided on separate networks. For example, telegraph networks, telex networks, telephone networks, Facsimile networks, Cable networks and Data networks support different services, as their names would suggest. These networks possessed characteristics that satisfied the peculiar requirements of the service they provided. For example, the voice network would support bandwidths of 64 Kbps for voice communication and would ensure Telco-grade voice communication with little jitter and echo cancellation [1][2]. Likewise, the cable networks would provide even higher bandwidth and improved quality of service (QoS) for video transmission. On the other hand, the data communication networks’ bandwidth and QoS requirements are highly flexible. For most types of data communication applications, reliability is critical, which means that the delivery protocols would implement mechanisms for error checking, acknowledgment, re-transmissions and sequencing. On the other hand, for real-time applications such as voice communications, it would make little sense to retransmit a lost packet for play back at the receiving end, if it is out of sequence and is considerably delayed. Essentially, the main point to be noted is that these networks have been designed differently in terms of their underlying architecture and communication protocols.
With the immense growth of digital networks, which is the marriage of two technologies i.e. telecommunication technology and computer technology, Networks are being explored to the fullest. Ways, in which existing networks can be used optimally, with minimum additional cost, include facilities like video conferencing and mail serving incorporated into the network, saving cost, granting easier access to remote database and remote programs. Integrating these networks into a single integrated network, such that all services would use common facilities, presents a technological hurdle [3][4].
This project therefore is designed to provide a service that transmits voice and video over a Data network, as against having dedicated voice and cable networks meant for either voice or video communication only.
The advantages gained from having an all-purpose network as against having only dedicated networks include Cost Reduction, Simplification and Consolidation.
With the implementation of software-based intercom, the need for expensive PABX and telephone handsets would be eliminated since the only hardware requirements needed would be headsets and computers on network. Moreover, with the prevalence of Internet Protocol (IP) nodes and the abundant supply of IP based switches and routers, communication might not be limited to just LAN, but may include Wide Area Networks (WAN), thereby reduced the cost of making long distance calls. In addition, simplified installation and maintenance are major advantages the project will offer.
The major aim of this design therefore is to develop a LAN-based software intercom where anyone on the network can dial a peer that is logged onto the same network. This is an intercom without the PABX and expensive handsets. Another aim of the software intercom is to provide video peer-to-peer conferencing, where two or more clients can see each other in real-time using webcams or any other video capture devices connected to their computers.