Santa Clara-based 3Com Corp claims that it was the first vendor in the data networking industry to demonstrate 100Mbps Ethernet when it showed off its skills in Boston last week. The purpose was to make it clear that the IEEE 802.3 CSMA/CD Media Access Control protocol layer can run effectively at 100Mbps. The demonstration included two MS-DOS client personal computers each running NetWare and connected to a server running NetWare 4.0. One client ran 10Mbps Ethernet and the other 100Mbps Ethernet to the server. Observers say that both clients were shown continuously reading a 64Kb file from the server. The 100Mbps client took 17 seconds to read 156Mb while the 10Mbps client required two minutes, 26 seconds to read the same amount of data. 3Com is arguing for retention of the Media Access Control protocol on grounds of low incremental cost, simple migration and investment protection – but the test was over coaxial cable rather than unshielded twisted pair. As reported, Hewlett-Packard Co and AT&T Co are proposing 100BaseVG voice grade technology which uses a demand priority access scheme implemented in a hub.
