stp bpdus

amms68958 · ‎02-02-2006

Hi,

In a trunk port ,can I know the vlan through which the stp bpdus are sent

in Cisco.

Thanks in advance

pkhatri · ‎02-02-2006

STP will be run on a per-VLAN basis therefore separate BPDUs will be sent on each VLAN ...

Is that what you were asking ?

Paresh.

amms68958 · ‎02-02-2006

Thanks for your response.

Here I am asking about the trunk port.What I thought is that STP bpdus are sent (untagged)in native vlan in a

trunk port.May be someone can correct me if my understanding is wrong.

I am wondering about the STP interoperability with any other vendors whose native vlan is not designed as vlan 1 by default.

Can someone pls give a detailed explanation on this..

Francois Tallet · ‎02-03-2006

The BPDUs for vlan 1 are always sent untagged to the IEEE address on 1q links, regardless of the native vlan. This is because when running PVST+, vlan 1 is the CST, the unique STP defined in the IEEE specification.

Cisco also sends BPDUs on each and every vlan to a proprietary address, flooded by third party bridges.

If you are running MST, BPDUs will only be sent untagged to the IEEE address. There will be no proprietary BPDUs (this is a pure IEEE standard implementation).

regards,

Francois