A look at local area networks and some of its variants: With a special reference to Bharat Electronics Limited

India, as a country, has been very lucky with regard to the introduction of telecom products. The first telegraph link was commissioned between Calcutta and Diamond Harbor in the year 1852, which was invented in 1876. First wireless communication equipment were introduced in Indian Army in the year 1909 with the discovery of Radio waves in 1887 by Hertz and demonstration of first wireless link in the year 1905 by Marconi and Vacuum Tube in 1906. Setting up of radio station for broadcast and other telecom facilities almost immediately after their commercial introduction abroad followed this. After independence of India in 1947 and adoption of its constitution in 1950, the government was seized with the plans to lay the foundations of a strong, self-sufficient modern India. On the industrial front, Industrial Policy Resolution (IPR) was announced in the year 1952. It was recognized that in certain core sectors infrastructure facilities require huge investments, which cannot be met by private sector and as such the idea of Public Sector Enterprises (PSR) was mooted. With telecom and electronics recognized among the core sectors, Indian Telephone Industry, now renamed as ITI Limited, was formed in 1953 to undertake local manufacture of telephone equipment, which were of electro-mechanical nature at that stage. Hindustan Cable Limited was also started to take care of telecom cables.

Bharat Electronics Limited (BEL) was established in 1954 as a public Sector Enterprise under the administrative control of Ministry of Defense as the fountainhead to manufacture and supply electronics components and equipment. BEL, with a noteworthy history of pioneering achievements, has met the requirement of state-of-art professional electronic equipment for Defense, broadcasting, civil Defense and telecommunications as well as the component requirement of entertainment and medical X-ray industry. Over the years, BEL has grown to a multi-product, multi-unit, and technology driven company with track record of a profit earning PSU.

[...] A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP?s network. Routers are located at gateways, the places where two or more networks connect. Routing is a process preformed by a router which moves packets of data around the Internet. A router makes sure that a message is sent and received and is part of what makes TCP/IP such a useful protocol suite. To be able to successfully start routing a router uses headers and a forwarding table to find the destinations for packets. [...]

[...] Combing Vlans with ATM networks creates a new set of issues for network managers , such as relating Vlans to ATM emulated LANs (ELANS), and determining where to place the routing function. VLANs Transparent to ATM In a LAN backbone with Vlan spanning more than one Lan switch. In an environment where ATM exist only in the backbone (that is there are no ATM- connected end stations), ATM permanent virtual circuits (PVCs) may be set up in a logical mesh to carry intra Van traffic between these multiple LAN switches. [...]

[...] Despite the frequently quoted numbers illuminating the hidden costs of networking, such a administration and moves/adds/changes, customers realize that Vlans have their own administrative cost, both straight forward and hidden Although many analysts have suggested that Vlans enhance the ability to deploy centralized servers, customers may look at enterprise wide Vlan implementation and see difficulties in enabling full high performance to centralized servers. Defining VLANs What is Vlan? With the multitude of vendor specific Vlan solutions and implementations strategies, defining precisely what Vlans has become a contentious issue. [...]