On 11/26/13 1:45 PM, Dino Farinacci wrote:
But what if the service being provided is L3? In this case TSes are
only sending IP packets, but all TSes are directly reachable (i.e.,
without leaving the VN). What expectation do TSes in this type of
situation expect of the TTL processing?
Thomas,
I think there are two different ways to view an L3 service:
1. A closed user group which is larger than a single IP subnet,
provisioned as part of setting up the VN.
2. A more efficient way to pass around IP packets; no need to have an
(inner) Ethernet header if the TSs only care about IP.
I reality it is a combination of the two. The administrator that
provisions the VN see the CUG aspect of #1. The TS and NVE
implementations see the #2.
"Directly" needs to be defined above. If the two TSes are in the same subnet
then it would behave as it does today (when 2 hosts are connected to hub - I don't say
switch because I don't want to complicate the discussion).
Do they even care?
If I am 10.0.0.1 in CA on subnet 10.0.0.0/8 and you are 10.0.0.2 in NY on
subnet 10.0.0.0/8 and we are reachable via the overlay, I expect one line if
output from traceroute. If you are 11.0.0.1 I expect at least 2 lines of output.
Dino,
I think what you are saying is that from a host/TS perspective you'd
expect an L3 service to have the same TTL behavior as when using a L2
service with routers that are external to the VN.
That makes a lot of sense to me.
In that way the size and shape of the L3 VN/CUG doesn't impact the TTL
handling.
Erik
_______________________________________________
nvo3 mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/nvo3
