[89059] in North American Network Operators' Group
Re: shim6 @ NANOG (forwarded note from John Payne)
daemon@ATHENA.MIT.EDU (Randy Bush)
Wed Mar 1 18:30:12 2006
From: Randy Bush <randy@psg.com>
Date: Thu, 2 Mar 2006 07:29:34 +0800
To: Joe Abley <jabley@isc.org>
Cc: NANOG list <nanog@nanog.org>
Errors-To: owner-nanog@merit.edu
>>> How about some actual technical complaints about shim6?
>> good question. to give such discussion a base, could you
>> point us to the documents which describe how to deploy it in
>> the two most common situation operators see
>> o a large multi-homed enterprise customer
> There are no documents describing deployment. Probably there should be.
>
> The general approach is presumably well-known (for those for whom it
> is not, go browse around <http://www.ietf.org/html.charters/shim6-
> charter.html>, and perhaps in particular <http://www.ietf.org/
> internet-drafts/draft-ietf-shim6-proto-03.txt>.
>
> Deployment in an enterprise is a matter of:
>
> (a) deploying hosts with shim6-capable stacks within the enterprise;
>
> (b) arranging for those hosts to receive addresses in each PA
> assignment made by each transit provider (multiple PA addresses per
> interface), e.g. using dhcp6;
>
> (c) optionally, perhaps, installing shim6 middleware at some
> suitable place between host and border in order to impose site policy
> or modulate locator selection by the hosts.
and this last will handle the normal site border (and these days
intra-site, e.g., departmental, borders) issues such as
o dns within the enterprise is isolated from that of outside
o firewalls, algs, and sometimes nats
o security policy in general
o load balancing between upstreams
o ...
i.e, what handles the impedance mismatch between the goal, which
is *site* multi-homing, and the tool, which is *host* multihoming?
and how does it handle it, how is it managed, ...?
> You will note I have glossed over several hundred minor details (and
> several hundred more not-so-minor ones). The protocols are not yet
> published; there is no known implementation.
possibly this contributes to the sceptisim with which this is viewed?
>> o a small to medium multi-homed tier-n isp
> A small-to-medium, multi-homed, tier-n ISP can get PI space from
> their RIR, and don't need to worry about shim6 at all. Ditto larger
> ISPs, up to and including the largest.
as it is not yet clear if small isps can get pi space, and the issue
of multi-homing is central to the discussion of this issue, and
routing table growth is another vector here, perhaps this needs to be
explored a bit more.
randy