Is multihoming hard? [was: DNS amplification]

Sat Mar 23 00:44:14 UTC 2013

On 3/20/13, John Curran <jcurran at istaff.org> wrote:
> On Mar 20, 2013, at 2:25 PM, Owen DeLong <owen at delong.com> wrote:
>> However, if there were motivation on the provider side, automated BGP
>> configuration could enable consumers to attach to multiple providers and
>> actually reduce support calls significantly.

Do you really think making a large SP making theirt customers'
configuration more complicated,  using a protocol at a scale its
implementations were never designed for, will amount to a reduction in
net average support costs?

See...  I think there is an economic argument to made against massive
multihoming; upward sloping supply curve situation,  ultimately  slots
in the global routing table are a competitive market. Providing
service to a network that wants to be multihomed could be expected to
incur a greater marginal price on the provider (additional overhead to
implement, maintain, and service the more complicated service).     If
that added price tag exceeds the amount that the customer values their
marginal benefit from multihoming,  then requiring multihoming  hurts
the provider, because a lesser quantity is purchased, and hurts the
customer, because their  increased payment in excess of the benefit is
added cost.

The more multihomed customers,  the more routes,  the greater the
marginal cost of adding every BGP router,  the greater cost of every
route advertised,    which you could speculate the tier1's will
ultimately be passing onto service providers,  and then the customers,
in due time.

The increased price tags reduce the quantity of services purchased.

> If you can figure out a way to persuade service providers of this belief,
> I would ask that you also persuade them that they have to offer dual-stack
> for all of their customers (which may have already resulted in them losing
> a small number of customers who expected IPv6 by now... :-)

Until people are actually using dual-stack services, the current
perceived benefit is $0,
so it's really a tough argument to make.

You have to rely on the prediction,  that within a few years,
dual-stack services will provide the  added benefit of full internet
reachability, and   ipv4-only services will have significant
impairments.

> Thanks!
> /John
--
-JH