RE: draft-bonica-tunneltrace-02

[Shahram Davari <Shahram_Davari@pmc-sierra.com>]

Eric,

> Shahram> 2) TTL expired user packets will now be forwarded to 
> UDP module
> Shahram>    instead of being dropped. Which could overload 
> the UDP module in
> Shahram>    certain situations.  
> 
> TTL-expired user packets are not simply dropped today; they 
> are forwarded to
> the ICMP module  to cause the generation of an  ICMP message. 
>  Usually there
> is some sort of limit placed on the number of packets that 
> can be queued for
> ICMP processing, or the  number of such packets that can be  
> seen in a given
> amount of  time, etc.  The  marginal overhead to  see whether 
> a  packet that
> makes it through to ICMP processing  is a GTTP packet doesn't 
> seem like that
> big a deal.
> 

What about the TTL expired MPLS packets? Should it be forwarded to the
ICMP module too? How does the system find that this is a GTTP packet or 
a user packet (consider non-IP user payload)?

-Shahram