19 Aug
2005
19 Aug
'05
8:17 a.m.
Paul Koning wrote:
It's all over IBM's internal network NOC's. I seem to remember one of
the larger ISP's fairly near here still using it in their NAP. I could
probably find out who, if necessary.
That, and this is classiccmp. Old != obselete.
Peace... Sridhar
FDDI and 100BaseT are the same speed given equally
competent
implementations.
With 100BaseT using an MTU of 1500, and FDDI using an MTU of 4478? I
don't believe there's a standard for jumbo frames on 100Base-T.
Sridhar> That's not even talking about
fault-tolerance.
Ethernet and FDDI both offer fault tolerance. They do it in different
ways, but they both can do it.
Having spent several years in the FDDI ANSI committee, I know all the
"why FDDI is better" FUD. It doesn't hold water. And it certainly
doesn't justify the absolutely mindboggling complexity of FDDI
compared to Ethernet.
Take a bunch of SAS CDDI cards, plug Cat 5 into them, plug other end
into concentrator. Voila. Done. Where's Need to run it a couple miles
down the road? No problem. Not everything has to be backbone dual
counter-rotating rings with trees.
That, and now that the hardware is out of fashion, it's a lot cheaper.
I have some GigE and some FDDI running over fiber between buildings here
at work, and the GigE's redundant failover capacity often takes special
hardware ($$), and often doesn't work as well.
> You can
run IP over it, of course. And then you could run iSCSI,
> if you don't mind the slow performance. But FDDI was obsolete
> long before iSCSI came out. So an FDDI to SCSI converter would
> have to be a proprietary hack.
Sridhar> Obselete? It's still very much used in places where fault
Sridhar> tolerance is important.
You're thinking about the U.S. Navy? I heard from them a few years
ago when they realized that FDDI was dead, dead, dead, and they had to
look for alternatives, because new FDDI hardware could no longer be
obtained anywhere.