Re: multi-homing vs multi-connecting

[Pekka Savola <pekkas@netcore.fi>]

On Thu, 2 Jan 2003, J. Noel Chiappa wrote:
>     > the terms "multi-homed" (always different ISP's) and "multi-attached"
>     > (same ISP) are separated.
>     > I don't think this terminology has been well established? At least as
>     > far as I've seen, multihoming has been used to refer to both (to some
>     > extent).
> 
> Another place where one term, "multi-homing", has been used to cover two
> fairly different things are with so-called "site multi-homing"  and
> "host multi-homing" - the latter being a single host with multiple
> physical interfaces.

Hmm.. I group these differently (though I can see why the above could also
be a useful classification), basically:

1) Host multi-homing (strictly speaking, "node" multihoming..)
 a) multiple interfaces and addresses: e.g. a mobile device with both 
GPRS+WLAN interface active
 b) one interface and more addresses: network is providing multiple 
prefixes (of possibly different properties).  It is the _host's task_ to 
deal with the issues.

 * a special case of either a) and b) are mechanisms employing a mapping
function between addresses (HIP, MIPv6 to a lesser degree of success) or
parts of addresses (LIN6).

2) Site multi-homing

 Either something like 3) possibly restricted a bit or the framework for 1)

3) ISP multi-homing
 * BGP-only, trivial case


.. so it would seem you'd rather place 1.b) under 2) as a network 
providing multiple prefixes is a already a site.  From IPv4 perspective, 
it's definitely more in the 1), but in IPv6, perhaps a bit closer to 2).

Does this make sense?  Thoughts?

(Actually I'm writing a thesis on the subject.. :-)

-- 
Pekka Savola                 "Tell me of difficulties surmounted,
Netcore Oy                   not those you stumble over and fall"
Systems. Networks. Security.  -- Robert Jordan: A Crown of Swords