Push for short-wavelength Fast Ethernet standard
By STEPHEN HARDY
To address an obstruction in the path toward fiber-to-the-desk, 22 companies have joined to create the Short Wavelength Fast Ethernet Alliance. Sponsored by the Fiber Optics lan Section of the Telecommunications Industry Association, the alliance hopes to create an 850-nm specification for 100-Mbit/sec Fast Ethernet transmission over optical fiber. It was recently made a task group of the Telecommunications Industry Association`s Fiber Optic Group 2.2.
The standard is necessary, say proponents, because while Ethernet standards for optical fiber call for 850-nm transmission, the existing Fast Ethernet standards center on 1300-nm transmission. The wavelength disparity makes upgrading from Ethernet to Fast Ethernet cumbersome and expensive--which would continue to make copper a more attractive medium for such applications.
As currently envisioned, the standard will enable full-duplex Fast Ethernet transmission with 850-nm light-emitting diodes over a minimum distance of 300 m while maintaining interoperability with the installed base of 10Base-FL fiber-optic Ethernet links. The alliance plans to copy polarization-mode dispersion limitations from Fiber Distributed Data Interface where possible to maintain compliance with 802.3u standards.
Auto-negotiation with current 850-nm Ethernet devices also will be a priority. This initiative will attempt to minimize implementation costs, provide auto-negotiation between current 10Base-FL and the new swl-based 100-Mbit/sec Fast Ethernet systems, accommodate parallel-detect non-negotiating devices, support full-duplex operation, and enable optional implementation of this function.
Two task groups, which meet weekly via conference calls, have been formed to address these issues. The alliance hopes to stage its first demonstration of 850-nm standard Fast Ethernet transmission at the Networld+Interop show this October in Atlanta.
Member companies in the alliance include 3M, Allied Telesyn International, Allayer, amp, batm, Berk-Tek, Belden Wire & Cable, Canary, Commscope General Instrument, Connectronix, Corning, Honeywell, lanart, lancast, Lucent Technologies, Micro Linear, Ortronics, Siecor, SpecTran, Sumitomo Electric Lightwave, Sundance Technology, and Transition Networks. q