In message <20060218231847.GA8767@blar.home.comstyle.com>, Brad writes:
>On Sat, Feb 18, 2006 at 03:15:36PM -0800, John Nemeth wrote:
>> On Jul 11,  1:30pm, "Liam J. Foy" wrote:
>> } 
>> } Just as a side note, CARP is basically now completely working. The
>> } last remaining issues have been resolved now.
>> } 
>> } Hope to have a patch ready within the next few days(against HEAD).
>> 
>>      Do we know whether or not CARP violates Cisco's patent?  I.e. is
>> bringing CARP in a wise idea?  We should probably just implement VRRP
>> as it is the standard and Cisco has said they will allow people
>> implementing it to use their patent.  A different protocol, such as
>> CARP, may get us into trouble.
>> 
>> }-- End of excerpt from "Liam J. Foy"
>
>You're confusing CARP with VRRP. It is the other way around.
>

No -- VRRP is definied in RFC 3768 as an IETF Draft Standard.

As for IPR -- Cisco has not made such a statement, at least to the 
IETF.  http://www.ietf.org/ietf/IPR/cisco-ipr-draft-ietf-vrrp-spec-v2.txt
is the latest document filed there; it provides for "reasonable,
non-discriminatory terms".   IBM has also made a claim (and a similar 
offer); see http://www.ietf.org/ietf/IPR/ibm-rfc2338-rfc2787.txt

CARP is OpenBSD's protocol to avoid the patent.  See
http://www.openbsd.org/lyrics.html#35 .  Also note that CARP runs as 
protocol 112, the same as VRRP, as a political statement by OpenBSD -- 
it doesn't "conflict with anything else of value".  

		--Steven M. Bellovin, http://www.cs.columbia.edu/~smb