Dot1q tunnel question

amitbatra · ‎05-27-2008

hi guys,

just a qucik question.

i am planning to configure Dot1q tunnel in my network. becoz i need to hide some vlans. my concern is , when we configure Dot1q tunnel . what happens to the cos marking on the original dot1q packet ? are they coppied to the newly imposed tunnel tag ?

n.nandrekar · ‎05-28-2008

It is possible to maintain the inner vlan mapping or to change the mapping on the outer tag.

Read the section " QOS AND COS MUTATION WITH 802.1Q TUNNELING" in the following link....

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/prod_white_paper09186a00801f1cc3_ns577_Networking_Solutions_White_Paper.html

Cheers!

Niranjan

Pavel Bykov · ‎05-29-2008

It all depends on the hardware.

For example 3750 Metro support copying inner CoS value to the outer tag. It is also supported by 4500s with SUPV-10GE.

Also this functionality is possible with ES20 cards in 7600.

Overall there is not much hardware that support it. The functionality you are looking for is called "ntelligent IEEE 802.1Q tunneling QoS"

http://www.cisco.com/en/US/docs/switches/metro/catalyst3750m/software/release/12.2_25_seg_seg1/configuration/guide/swtunnel.html#wp1010491