two perspectives on "site" multihoming

[dhcnotice <dhc@dcrocker.net>]

Brian,

BEC> Firstly, this is not the MANET WG, and we are clearly chartered by
BEC> the IESG to work on site multihoming in its classical sense, where
BEC> if we come down to basics, the main goal is to prevent a BGP explosion.

There are two different strategic ways to approach site multi-homing.

One is at the site-level, of course. Hence the focus is on network-level
mechanisms. An example would be a network-agile method of addressing
while holding the host portion constant, and then filling in the correct
network portion at the exit router.  Presumably this would leave the
host untouched.

The other approach is at the host-level, where the exit router is
essentially unaware of the mechanism -- return filtering issues
notwithstanding. The model has the host do all the work and can, in
fact, leave the exit router unchanged. So, the host is address-agile.

It is worth noting that this approach has the option of being
implemented at the site level, largely transparent to the host, for easy
adoption by sites. Or it can be adopted at the host level, for easy
adoption by those hosts, without having to recruit site administration
to the effort.


d/
--
 Dave Crocker <dcrocker-at-brandenburg-dot-com>
 Brandenburg InternetWorking <www.brandenburg.com>
 Sunnyvale, CA  USA <tel:+1.408.246.8253>