We are in the age of WLANs, however, when M R Krishnan and R Ramanan ventured out to develop the first LAN in India about eighteen years back, there were some interesting challenges they had to face. Let us take a look at how the first LAN in India saw the light of the day. (Krishnan and Ramanan were both working for the TCS Networking team in 1990. Today, Krishnan works as VP – NSE Infotech services while Ramanan works as MD – CMC.)
“I was part of the Networking team at TCS, where we developed the first indigenously built LAN of India called FALCON (Fast Access Local Area Network) even before the Ethernet LAN standards came in,” says Krishnan. For this indigenous LAN development, the efforts of both Krishnan and Ramanan were recognised and awarded by IEEE (Institute of Electrical and Electronics Engineers) in 1990.
The first LAN implementation was done at Tata Steel, followed by one at VSNL, Mumbai. The FALCON LAN was also implemented at the Army Headquarters in Delhi. “In those early days, we used an Ethernet like indigenous CSMA/CD Protocol and the network speed was 2 Mbps,” explains Krishnan. The LAN was implemented using coaxial cable and bus architecture. The LAN card itself was built using 75 discreet ICs and a Z80 Microprocessor. Getting the LAN card fabricated at the NELCO factory was also a challenge.
“We had used thin coaxial cables and T-connectors to physically connect one PC to the other. There was a limitation that you cannot have more than 30 PCs in a single LAN segment. There was also a maximum distance limitation of 200 metres. In order to overcome this distance limitation, we designed hardware repeaters, which could extend the LAN by a further 200 metres. If the building was a large one like the Army Headquarters, we had to use a thick coaxial cable, which would cover a distance of up to 500 metres,” says Krishnan. The problem with the coaxial cable LAN was that in case a break or crack affected the cable somewhere, the entire Network would come to a standstill due to the bus architecture. Subsequently, we had to run around and figure out the exact location of the cable malfunction.
At VSNL, we had to deploy the cable right from the top floor to the ground floor alongside the lift shaft. We also had to make sure that the path of the cable layout was not surpassing 500 meters so the shortest possible route had to be worked out. There was no standard e-mail software at that time, so we wrote our own e-mail software too.
The signal would run weak after 500 meters so we developed an indigenous BRIDGE Software to interconnect two LANs of 500 meters each to enable LAN-to-LAN communication.
Later in 1992/1993, when standard 10 Mbps Ethernet cards became commercially available, we migrated the FALCON software to run on these Ethernet cards.
SAIL was the largest customer of FALCON LAN and used it for their Sales Order Processing at all their branches and stockyards for an entire decade from 1990 to 2000.