Adapting FDDI to gigabit transmission rates
Włodek Dobosiewicz, Paweł Gburzyński · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1993
The FDDI ring-protocol combination is well-suited for large local (`campus') area networks. However, for larger networks, FDDI users suffer excessive access delay, even under very light traffic. Moreover, FDDI achieves full capacity only in special circumstances, and heavy load is not a sufficient condition for achieving it. We propose a modification of FDDI that has none of these deficiencies. By changing the interpretation of holding the token, we get a protocol that allows every station to transmit when the link is silent. The resulting token-passing protocol yields a capacity-1 network even for modest values of TTRT. Additionally, stations endure a very small access delay under light load. All the other properties are identical to those of FDDI. The proposed protocol uses standard FDDI components. Moreover, the protocol is compatible with FDDI to the point that it works correctly even if some of the stations attached to it operate under the original FDDI protocol (those stations will get the performance offered by FDDI, while the stations using the new protocol will get a larger bandwidth and a lesser access delay).