| 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 |
Design of FDDI networks appears to be very simple as compared to
Ethernet or 802.5 design when looking at the general specifications.
IE. 200 km fiber and 1000 connections maximum.
One would think that as long as you use the specified fiber, you
could build an FDDI network without much thought.
I know there must be more to FDDI design than this. Some issues that
become obvious to me include conditions during a cable or component
fault. Do the FDDI specifications deal with this clearly? I would
guess that one should design the network such that you assume the
network to operate in a failed condition. In this state, the signal
would traverse through each node twice (assuming the stations are
not connected to an intelligent concentrator) on it's trip around
the ring therefore each station should count twice in the total
station calculation. Is this correct? Along with this thought, the
fiber connecting these stations would also count twice in calculating
the overall circumference of the ring. Is this correct?
What other issues need to be considered during the design of FDDI?
I consider these issues to be beyond the scope of DFON as DFON is
limited to cable plant design and not intended to deal with the
specific products on the cable plant and how to configure them to
operate beyond providing adequate light and bandwidth.
Will there be a Digital FDDI design guide published prior to product
release? I have a number of customers who have recieved PID
presentations on FDDI and are requesting design assistance today.
Who would I, as an NWSS NPC, call to obtain additional information
today on proper FDDI design?
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 16.1 | FDDI isn't much different | CVG::PETTENGILL | mulp | Thu Nov 02 1989 22:33 | 16 |
I'm tired so perhaps that's why I don't understand what you're asking. FDDI networks follow the same basic principles other LANs: 1. Radial wiring a la Thinwire, except the coax is a pair of fibers and the DEMPR is a FDDI cable concentrator. 2. Divide the LAN into zones of modest size using cable concentrators in place of repeaters and by using bridges. 3. Limit the number of number of users impacted faults by using routers to partition LANs. FDDI doesn't represent a fundemental change in LAN technology. In fact, I'd argue that FDDI requires a substantial investment to just equal the simplicity of Ethernet. | |||||