[trill] Two comments on draft-ietf-trill-aa-multi-attach-00

[Haoweiguo <[e-mail]>]

Hi Mingui,

In section 5.3.1, no duplication mechanism is described. I think DF election should be used instead of HASH mechanism.

It's hard to realize consistent cross RBridge HASH algorithm, each RBridge should know other RBridge's local port and port up/down state, i have not ever seen similar implementation in industry.



In section 5.3.2 , split-horizon mechanism is described. I think the solution had better add local bias forwarding procedures.

I think the solution should be local bias forwarding plus split-horizon based on ingress nickname. What's local bias forwarding behavior? If there are multiple ESs(assuming ES1 and ES2 are in same VLAN) are connected to same RBridge of RB1,  when RB1 receives BUM traffic from ES1, it should local forwarded to ES2 no matter the DF state on the port connecting to ES2, this is called Local bias forwarding behavior.
Then RB1 injects the BUM traffic to TRILL campus and forward to RB2, if local port belongs to a MC-LAG and the MC-LAG attaches to RB1, then RB2 should drop the traffic to the local port based on ingress nickname tracking and filtering.



Thanks

weiguo