Re: Draft of updated WG charter

[Jay Ford <jay-ford@uiowa.edu>]

On Fri, 9 Jan 2004, vijay gill wrote:
> Routing update validation should be orthogonal to the multihoming
> solution.  Also, I am going out on a limb here and say that any
> m-homing solution that requires end-host updates is a non-starter
> from the get-go.

I'll go further out on that limb & say that any multi-homing solution which
requires substantially more intelligence in end systems than is currently
required for multi-homed IPv4 is bound to fail, even if you somehow get it
deployed.

This is really the heart of the IPv6 scalability issue.  I've never
understood the argument that multi-homing for IPv6 ought not be done the way
it's done for IPv4 (single address per end system, multi-path routing) on the
basis that the network can't tolerate the increase in routing table
size/complexity.  My objection is that the alternative (shoving the
complexity to the end systems) is much worse because:
   o  as evidenced by worm attacks..., the end systems are the worst managed
      pieces in the whole puzzle run by users who don't (& I'd say shouldn't
      be expected to) understand the workings of the network;  predicating
      routing-type functionality on that platform is asking for trouble
   o  there are at least 3 (4? 5?) orders of magnitude more end systems than
      there are routers, so embedding significant pieces of networking
      functionality in end systems greatly increases the likelihood of
      trouble & even more greatly decreases the chance of consistent
      operation over time

Consider the current difficulty in deploying changes to other technologies
due to system-level inertia (e.g., ASM->SSM for multicast).  Those are
relatively upper-level things which for the most part don't affect the basic
ability to get packets delivered.  Moving routing-type burden to the end
systems creates such inertia for basic packet delivery, making the network as
a whole even less upgradable than it is now.

I advocate keeping the end systems as simple as possible & dealing with the
routing support required to make multi-homing work close to the way it works
for IPv4.

________________________________________________________________________
Jay Ford, Network Engineering Group, Information Technology Services
University of Iowa, Iowa City, IA 52242
email: jay-ford@uiowa.edu, phone: 319-335-5555, fax: 319-335-2951