RE: Optical Connectors
Since you called me out on this one, I feel compelled to respond.
I have been involved in a number of optical "connector confrontations" (a
name with nice alliteration) in both application and cabling standards.
In the mid 90's the debate was between the defacto-standard ST and the
duplex SC. The SC offered the same performance, but added the duplex
feature, which was deemed to be of value. It entered the structured cabling
standards by some political maneuvering, and co-exited with the
"grandfathered" ST. Applications like Low Cost FDDI and 100BASE-FX endorsed
the duplex SC, so it gradually became the preferred connector over a 5 or 6
In the latter 90's SFF connectors appeared, leading to a series of new
connector confrontations. The biggest of these battles occurred in 802.3
during GbE development. The structured cabling standards also hosted such
debates. In all of these cases the outcome was the same - a stalemate. No
one SFF connector got consensus. Only one standards body has been able to
make a choice of a single SFF connector; IEEE 1394B (High Performance Serial
Bus) selected the LC.
Seeing this trend, the sentiment shifted from one of confrontation to one of
cooperation. The industry knew that the SFF connectors offered a better
solution, so rather than continuing to deadlock, standards and other forums
started reaching consensus in one of two ways. Some selected specific SFF
choices (ATM Forum, Fibre Channel). Others did not specify form factor, but
rather performance and intermateability requirements (Gigabit Token Ring,
TIA 568-B, ISO 11801). Gigabit Token Ring includes an informative annex on
three SFF connectors. These are the same three that appear in FC, namely the
SG, MT-RJ and LC.
The SFF connectors have been around now for a few years. The pack has
expanded to at least eight. But three have become most widely accepted in
various markets and applications. Those three are the ones specified in the
FC standard. My sense of the market, for applications using laser
transmitters, is that the LC has become the favored connector system. If
IEEE 802.3ae wishes to select a SFF connector, perhaps consensus already
exists. If not, then I would say 802.3ae should not spend time hosting
another connector confrontation, and simply adopt the same set as Fibre
From: Joel Goergen [SMTP:joel@xxxxxxxxxxxxxxxxxxx]
Sent: Friday, July 21, 2000 1:17 PM
Subject: Re: Optical Connectors
Actually, I can completely accept your points. I was hoping to hear
from Paul Kolesar and perhaps Steve Swanson, and maybe some others from the
connector/cable side. If most of you guys agree .... I certainly won't
argue with that!