RSTP port types

[carl_townshend]

Hi all, when we talk about rstp, we have 2 types of port edge and point to point, what is the difference between these ?

[Giuseppe Larosa]

Hello Carl,

a point-to-point port is a port where another switch is expected (STP partner here)

an edge port = access port where an end user device is expected (no STP partner here)

It is very important to classify edge ports in order to help RSTP to achieve the fastest convergence.

Hope to help

Giuseppe

[carl_townshend]

Hi there

So what is the difference between these ports? any spanning tree settings etc, as both ports listen and send bpdu's?

[Giuseppe Larosa]

Hello Carl,

no BPDUs are expected on edge ports : PCs don't send them

so the portfast settings and concept can be used on edge ports.

point-to-point ports: here STP BPDUs are expected and the handshake mechanism of RSTP can used to negotiate port role and state with the neighbor

Hope to help

Giuseppe

[hardiklodhia]

Hi,

In addition to above post check this link for more understanding

http://www.cisco.com/en/US/docs/switches/lan/catalyst3550/software/release/12.1_13_ea1/configuration/guide/swmstp.html#wp1008347

Hope this will help.