Subject: Re: Changing the PHY status reporting
To: Brad <>
From: Steven M. Bellovin <>
List: tech-net
Date: 02/18/2006 18:36:26
In message <>, 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 
is the latest document filed there; it provides for "reasonable,
non-discriminatory terms".   IBM has also made a claim (and a similar 
offer); see

CARP is OpenBSD's protocol to avoid the patent.  See .  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,