hargrove@bee.corp.sgi.com (Mark Hargrove) (06/02/91)
I've recently heard it alleged that using FDDI technology as a network backbone (as a way of aggregating multiple ethernets) would be a disaster. Further, I was told that FDDI is a very fragile technology, not suitable for production networks, not really suitable for much at all outside the lab -- and probably never would be. Does anybody with actual experience with running a large, production network that includes FDDI as an important part of the transport have a concurring or dissenting opinion about this? I've got some very important decisions facing me, and I don't want to do the wrong thing. -M
koning@koning.enet.dec.com (Paul Koning) (06/03/91)
|> |>I've recently heard it alleged that using FDDI technology as a network |>backbone (as a way of aggregating multiple ethernets) would be a |>disaster. Further, I was told that FDDI is a very fragile technology, |>not suitable for production networks, not really suitable for much |>at all outside the lab -- and probably never would be. |> |>Does anybody with actual experience with running a large, production |>network that includes FDDI as an important part of the transport have |>a concurring or dissenting opinion about this? I've got some |>very important decisions facing me, and I don't want to do the |>wrong thing. |> |>-M |> FDDI is certainly newer than Ethernet, so the number of people who understand it in detail is quite a lot smaller. It is also more complex than Ethernet. This certainly means that an FDDI network, put together by those who do NOT understand it, is more likely to give you trouble than the corresponding Ethernet. On the other hand, if you take the time to learn about FDDI, you should certainly be able to build a production network that works well. As an example, the site I work has two buildings, with probably well over a thousand nodes. A few miles away is another cluster of buildings with another thousand or so nodes. We've been using FDDI as the production backbone for these two sites for about 6 months now, with no problems. This includes a single-mode link between the two sites. (They are only a few miles apart, but we "folded" the link a couple of times to exercise the single mode technology at its 40 km distance limit.) I'd suggest you approach the subject with care and make sure you learn about what you're doing. But don't pay too much attention to the "chicken little" types out there. paul
jdudeck@polyslo.CalPoly.EDU (John R. Dudeck) (06/05/91)
In an article hargrove@bee.corp.sgi.com (Mark Hargrove) wrote: >I've recently heard it alleged that using FDDI technology as a network >backbone (as a way of aggregating multiple ethernets) would be a >disaster. Further, I was told that FDDI is a very fragile technology, >not suitable for production networks, not really suitable for much >at all outside the lab -- and probably never would be. > >Does anybody with actual experience with running a large, production >network that includes FDDI as an important part of the transport have >a concurring or dissenting opinion about this? I've got some >very important decisions facing me, and I don't want to do the >wrong thing. Well, I know that here at Cal Poly they are using FDDI as the campus backbone between various buildings, linking ethernets and other stuff together. It isn't all in place yet, but at least several of the ethernets are on it. I'm not really aware of whatever operational problems they have encountered, but it mostly seemed to be related to setting up routing tables in the Cisco routers at the FDDI nodes. I remember reading about some phone company in a city (don't remember which one) which is using FDDI in a city-wide network to provide connectivity to some big users. I realize I'm not speaking from my own experience. But I have never heard about FDDI being unsuitable for a backbone application. Where did you hear this? -- John Dudeck "You can only push jdudeck@Polyslo.CalPoly.Edu simplicity so far." ESL: 62013975 Tel: 805-545-9549 -- AT&T promotional brochure
jbreeden@netcom.COM (John Breeden) (06/05/91)
>In an article hargrove@bee.corp.sgi.com (Mark Hargrove) wrote: >>I've recently heard it alleged that using FDDI technology as a network >>backbone (as a way of aggregating multiple ethernets) would be a >>disaster. Further, I was told that FDDI is a very fragile technology, >>not suitable for production networks, not really suitable for much >>at all outside the lab -- and probably never would be. >> Sounds like techno-sales speak to me - whoever told you that has some other vested interest (or he's repeating someone else's garbage). The only negative for FDDI today is it's per port cost. -- John Robert Breeden, jbreeden@netcom.com, apple!netcom!jbreeden, ATTMAIL:!jbreeden ------------------------------------------------------------------- "The nice thing about standards is that you have so many to choose from. If you don't like any of them, you just wait for next year's model."
my@dunkin.nsc.com (Michael Yip) (06/10/91)
In article <23114@shlump.lkg.dec.com>, koning@koning.enet.dec.com (Paul Koning) writes: |> |> |> |> |>I've recently heard it alleged that using FDDI technology as a network |> |>backbone (as a way of aggregating multiple ethernets) would be a |> |>disaster. Further, I was told that FDDI is a very fragile technology, |> |>not suitable for production networks, not really suitable for much |> |>at all outside the lab -- and probably never would be. |> |> |> |>Does anybody with actual experience with running a large, production |> |>network that includes FDDI as an important part of the transport have |> |>a concurring or dissenting opinion about this? I've got some |> |>very important decisions facing me, and I don't want to do the |> |>wrong thing. |> |> |> |>-M |> |> |> |> FDDI is certainly newer than Ethernet, so the number of people who understand |> it in detail is quite a lot smaller. It is also more complex than Ethernet. Well, understanding FDDI protocol and SMT in detail is definitely NOT required. If a network adminstrator who installed Ethernet (10BaseT) before, then FDDi shouldn't be that much harder. Basically just hooking up workstations to FDDI concentrators (instead or 10BaseT concentrators). But if someone wants to get the most out of FDDI, he probably should study a few papers for half a day or so and he can probably design a FDDI network with good performance and high fault torelance(sp?). |> On the other hand, if you take the time to learn about FDDI, you should |> certainly be able to build a production network that works well. We have been using FDDI in our Lab for over 9 months and it seems to be working very well. We have some SUNs and quite a few PCs on that network. We run TCP/IP and use one of the SUn as a TCP/IP gateway between the lab and the main Ethernet backbone. We just installed fiber in our offices and we are planning to put FDDI concentrators up to connect workstations and file servers. FDDI is still very new. When people first installed Ethernet, they too ran into problems because they have no experience in Ethernet. -- Mike Yip my@berlioz.nsc.com