V6 still not supported

Owen DeLong owen at delong.com
Tue Mar 22 17:54:00 UTC 2022

> On Mar 21, 2022, at 12:21, Bjørn Mork <bjorn at mork.no> wrote:
> Owen DeLong via NANOG <nanog at nanog.org> writes:
>> Virtually every useful flow of packets in one direction requires a
>> relatively symmetrical flow of packets in the other direction.
> Packet captures are useful without anything being returned. It's not
> uncommon to use some sort of unidirectional tunnel to transport captures
> over an IP-network.

By definition, packet captures can’t be more than 50% of useful traffic and the
traffic they are capturing is almost certainly a bidirectional flow of some form.

I’m willing to bet that packet captures are well below 1% of all traffic.

I’m willing to bet that less than 25% of all packet captures are transported
Over unidirectional tunnels, though I admit I could be wrong about this.

> Same goes for logging. Traditional udp syslog is a one-way street.

True, but most environments I’m familiar with have been moving away from syslog in favor
of some form of guaranteed delivery, which requires a two-way street.

Also, if a significant fraction of your traffic is logging, you’re probably doing something wrong.
(Note the word “Virtually” in “Virtually all”).

> And I'm sure there are more examples.

Perhaps, but I still say that in terms of overall total traffic, they are mostly a rounding error.

> Not that I think it matters in this discussion, which appears more
> circular than bidirectional.

That’s probably fair.


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