Ethernet topology

I wanted to know which topology is best for optical ethernet ring system. Is it better to use dual redundant ring or fault tolerant ring?

Do you mean "ring" topology versus "mesh" topology?

With respect to suitable recovery times, I think it depends on the application. Generally speaking, ring topology seems to offer the best recovery times using the least amount of switches. The possible downside is that you may be locked into a switch supplier.

Acromag has a good whitepaper on Ethernet Media Redundancy. It highlights different redundancy schemes and provides benchmark recovery times. Here is the link:

http://www.acromag.com/pdf/Media_Redundancy.pdf

Donald Lupo
dlupo at acromag. com

Ring topology Ethernet networks are not necessarily proprietary. It is possible to implement them with open standards like Rapid Spanning Tree Protocol (RSTP, 802.1w). However RSTP can take quite a bit of time to converge after a topology change, resulting in delays on the order of many seconds.

Paul...