Mapping bridge priority to vlan id

[yamenginena]

Dear All,

in per vlan spanning tree (PVST) each vlan can have differnet bridge priority,

my question is without mac address reduction how swtich can map each priority to vlan id in bpdus received

thanks

[Peter Paluch · Accepted solution]

Hi,

without mac address reduction how swtich can map each priority to vlan id in bpdus received

PVST+ BPDUs are 802.1Q-tagged by their appropriate VLAN they belong to. Upon arrival, BPDUs are processed in their appropriate instance according to their 802.1Q tag. The extended system ID is never used to sort received BPDUs into appropriate VLANs (and thus STP instances) because the receiving device can not know whether the sender of the BPDU is using the MAC reduction or not.

Best regards,

Peter

[yamenginena]

Dear Peter

thanks