| Title: | FDDI - The Next Generation |
| Moderator: | NETCAD::STEFANI |
| Created: | Thu Apr 27 1989 |
| Last Modified: | Thu Jun 05 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2259 |
| Total number of notes: | 8590 |
I am working with a customer here in Boston who wants to install an FDDI backbone in his building. They currently occupy 15 floors with 2 closets on each floor. Since this is the first major FDDI configuration I've done here, I am confused as to what is the best way to lay this out. My original thought was to put a DAS connected concentrator on each floor. Since the fiber will be star wired to the Data Center, I realized that I would need a ton of fiber jumpers in the main fiber distribution panel to accomplish this (doesn't seen right). This also seems more failure prone! Would I be correct if I were to put multiple concentrators in the data center connected to each other via DAS and connect each floor via SAS connected concentrators and bridges? This may be a simple question but I want to be sure since this will be quite a few $$$.
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 354.1 | yes, you're correct | BAGELS::LEVY | Thu Sep 26 1991 14:17 | 10 | |
re: <<< Note 354.0 by BOSNET::COLUMBUS >>>
>Would I be correct if I were to put multiple concentrators in the data center
>connected to each other via DAS and connect each floor via SAS connected
>concentrators and bridges?
Yes, this is perfectly valid, and even preferred, because it minimizes
the extent of the dual ring. For floors that require higher
availability, you can dual-home to different concentrators on the dual
ring.
| |||||
| 354.2 | How would I set up the dual homing on each floor? | BOSNET::COLUMBUS | Thu Sep 26 1991 15:15 | 9 | |
Thanks for the quick reply.... How would you suggest I set up dual homing to different concentrators? Which port would connect to what. I looked in the NAC buyers guide configuration guidelines, but it is unclear to me how this would be accomplished. John Columbus | |||||
| 354.3 | KONING::KONING | Brivu Latviju! | Thu Sep 26 1991 18:40 | 20 | |
Read the FDDI Primer... Dual homing is very simple: rather than connecting only the B port "up", i.e., to the next higher level in the wiring tree hierarchy, connect both A and B ports that way. If at all possible connect them to different concentrators. A simple example: two concentrators on the dual ring, in the "main distribution frame" (the site hub). [you mentioned the "data center" for that; that's fine, or a separate hub room might be used.] Put concentrators on each floor. Any concentrator to which "important" things are attached has its A port connected to one of the hub concentrators, the B port to the other hub concentrator. Both of these connections are to M ports on the hub concentrators. Any "not so important" concentrator is just connected by its B port, to an M port on either of the two hub concentrators. Given 15 floors and a max of 8 M ports per dual-attached concentrator, you will of course need more than just two concentrators at the hub/dual ring. paul | |||||