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Route or switch over FDDI with 3550

I have 8 3550 switches each of which I need to connect to a dual FDDI ring, but am unsure whether I can connect them to the FDDI ring via their 1000Base-SX modules, and switch vlan traffic between them. I want to have vlan1 for management and vlan2 for all devices on all switches. This way I can use the CMS - Cluster Management software to manage all the switches.

Do I need a router to switch vlan traffic between switches because of the FDDI media, or can I just have one broadcast domain across the FDDI ring? Are there any encasulation issues or could I just have the links to the FDDI ring as ISL trunks?

The other option I think I have is to enable routing on all switches, segment the switches in to 3 vlans, connect them to the dual FDDI ring and route traffic between vlans with the switches setup for HSRP and Ip addresses on the 1000Base-SX interfaces.

Any help would be appreciated.


Re: Route or switch over FDDI with 3550

The 3550 does not support FDDI connections - just Ethernet. See URL below.

"Catalyst 3550 switches do not support Token Ring or FDDI media. The switch does not forward FDDI, FDDI-Net, TrCRF, or TrBRF traffic, but it does propagate the VLAN configuration through VTP"

New Member

Re: Route or switch over FDDI with 3550

Is there a difference between a FDDI ring and a Dual Fibre Ring?

I should have realised the 100Base-SX modules are Gigabit Ethernet and plug in using Fibre connectors. I think the Dual Fibre Ring will act as an ethernet bus, so I don't have to do anything special.

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