nanog mailing list archives

Re: Long hops on international paths


From: Mark Tinka <mark@tinka.africa>
Date: Tue, 18 Jan 2022 17:23:02 +0200



On 1/18/22 16:28, Saku Ytti wrote:

2) MPLS-TTL expires in transit
2a) generate TTL exceeded and put it back to tunnel, sending it to
egressPE, which is guaranteed to know how to return to sender

This is what we run - our core is BGP-free (LDP), so the traceroute value customers see will be the egress PE router.

2nd best is to tunnel, but the
RTT will confuse uneducated, or as it may be, hjghly educated, users.

It is very confusing, even for some educated users.

It's become less of problem, as years of educating users seems to have bedded in.

We could implement something like
https://ytti.github.io/icmp-eo-timestamp/draft-ytti-intarea-icmp-eo-timestamp.html
to offer correct forward latencies to P/LSR in 2a scenario.

I recall you and I chatted about this some 3 or so years ago. Do you know if anyone of the (un)usual suspects have implemented?

Mark.


Current thread: