Alexandar A - 2009-01-08


We are implementing RSTP on a new networking board which is customised for specific application in small networks. We need to implement 802.1d 2004 standard

We have used RSTP 802.1w 2001 simulator and ported for 802.1d 2004 standard. Right now we are facing some issues in detection of backup port during confirmance tests. What we have observed is backup port is detected only when two ports are connected in a loop back.

We also tried to connect the network in such a way that one port should become a backup port. But the port role is not changed to backup and continues to be in designated state.

Another question we have is whether a backup port is detected when a inferior designated message is received on a port (message priority less than that of received port priority). From the RSTP implementation what we see is backup port checking will happen only if you receive a superior BPDU on a port.

Please throw some light to this!

Best Regards,