> On Wed, 24 Mar 2021, 07:53 Vasilenko Eduard, <[email protected] 
> <mailto:[email protected]> <mailto:[email protected] 
> <mailto:[email protected]>>> wrote:
...
> On Mar 23, 2021, at 8:47 PM, Brian E Carpenter <[email protected]> 
> wrote:
> 
>> Tunnel packets *are* explicitly addressed to a node, so tunnel endpoints are 
>> performing host functions on packets. If those host functions being 
>> performed on tunnel packets at the tunnel endpoints require buffers, then 
>> buffers need to be available.
> 
> Yes, and tunnel entry points are hosts when they send an encapsulated packet.

Viewed from inside a tunnel, the tunnel endpoints are both hosts.

> There's a subtlety though, which is that the device that contains the tunnel 
> entry point on the downstream side of the packet flow is indeed a router on 
> the upstream side. Conversely,
> the device that contains the tunnel exit point is a host on the upstream side 
> and a router on the downstream side.

I disagree; a tunnel is a link. That link can easily be host-host.

A host that is router-capable (many OSes have a flag to ‘forward IP’ or not) 
can have forwarding disabled (host-only mode) and use tunnels just fine.

> Which is why the MTU for packets inside the tunnel is no business of anyone 
> upstream or downstream of the tunnel.

Agreed…

Though I would appreciate your thoughts on how to handle the errors in RFC2473 
as noted in draft-tunnels.

Joe

> 
>   Brian

_______________________________________________
Int-area mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/int-area

Reply via email to