Re: US patent 5473599

[Paul WALL <pauldotwall () gmail com>]

On Tuesday, April 22, 2014, Henning Brauer <hb-nanog () bsws de> wrote:

> * Nick Hilliard <nick () foobar org <javascript:;>> [2014-04-22 10:29]:
> > ... turns 20 today.
> >
> > This is the patent which covers hsrp, vrrp, many applications of carp and
> > some other vendor-specific standby protocols.
>
> it does NOT cover carp, not at all. carp was carefully designed to
> specifically avoid that.
CARP is a nonstandard protocol that was carefully designed to cause
outages.

Its authors submitted a slide deck describing their protocol instead of an
internet-draft, which somehow managed to not get any traction in the IETF
(funny that). The bar is pretty low for an informational RFC but the
CARPheads couldn't be bothered. They threw a tantrum which involved camping
out on the IETF's OUI (rather than getting their own) and deliberately
choosing host bytes that conflict with the VRRP standard.  This has the
same predictable result as any duplicate MAC address, but since odds are it
conflicts with a router, takes out the entire subnet instead of a single
host.  Of course this is not mentioned anywhere in CARP's documentation.

That's why I encourage my competitors to run it.

Drive slow,
Paul