[e2e] What if there were no well known numbers?

Joe Touch touch at ISI.EDU
Thu Aug 3 15:20:00 PDT 2006

John Kristoff wrote:
> Could the removal of well known numbers actually be a rousing change
> more fundamental to the Internet architecture than anything we've seen
> before, even more so than commercialization, Microsoft Windows
> implementation nuances, NATs and multihoming.  Indulge me for a momment.
> There is a Internet Draft that has as part of the file name
> "no-more-well-known-ports".

There's a somewhat related one called "draft-touch-tcp-portnames-00.txt".

> The basic idea is that DNS SRV lookups
> should be used to determine a unique port with which to get service
> from the intended destination server.

The above document explains why SRV records are not, IMO, a viable
alternative. They add an extra round trip of delay for first use which
can be avoided, and they endorse using the DNS as a place in which to
register names which are fundamentally under control of the endpoint anyway.

It also explains why 'portmapper'-like solutions may be better in
keeping control at the endsystem, but still require additional round
trip times.

As to blocking/opening ports based on number, that makes the assumption
that port number has meaning outside the two endpoints of a connection,
which it does not.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 250 bytes
Desc: OpenPGP digital signature
Url : http://mailman.postel.org/pipermail/end2end-interest/attachments/20060803/284b54f2/signature.bin

More information about the end2end-interest mailing list