[86186] in North American Network Operators' Group
Re: What is multihoming was (design of a real routing v. endpoint id seperation)
daemon@ATHENA.MIT.EDU (Robert Bonomi)
Tue Oct 25 08:57:23 2005
Date: Tue, 25 Oct 2005 07:56:29 -0500 (CDT)
From: Robert Bonomi <bonomi@mail.r-bonomi.com>
To: nanog@merit.edu
Errors-To: owner-nanog@merit.edu
> From owner-nanog@merit.edu Mon Oct 24 15:33:02 2005
> Date: Mon, 24 Oct 2005 13:31:17 -0700
> Subject: Re: What is multihoming was (design of a real routing v. endpoint id
> seperation)
>
> Stephen Sprunk wrote:
> [snip]
>
> >> Other people use this term in very different ways. To some people
> >> it means using having multiple IP addresses bound to a single
> >> network interface. To others it means multiple websites on one
> >> server.
> >
> >
> > That is virtual hosting in a NANOG context. Some undereducated MCSEs
> > might call it multihoming, but let's not endorse that here.
>
> Unfortunately, this is a common and "standards blessed" way to refer to
> any host with multiple interfaces/addresses (real or virtual). For example,
> from the "Terminology" section, 1.1.3, of RFC1122, "Requirements for
> Internet Hosts -- Communication Layers," says,
>
> Multihomed
> A host is said to be multihomed if it has multiple IP
> addresses. For a discussion of multihoming, see Section
> 3.3.4 below.
>
*sigh* Multi-homing simply means 'having external connections to more than
one network' -- be it a network with multiple, disjoint, ingress/egress paths,
or a host with interfaces (real or virtual) on distinct LAN subnets (even if
those subnets are agregated into a single net somewhere upstream.
A host with multiple adresses utilizing the _same_ netblock/netmask _should_
_not_ be called multi-homed (because there is only one path to that host), it
is simply a single-homed host with multiple identities. might be called
"poly-ip-any" or some such. <grin>
