[nsp] HSRP protocol extensions?

[Ed Ravin]

On Mon, Jul 07, 2003 at 09:31:05AM -0400, Papo, Rick wrote:
> I have several packet traces showing this.  I had come to the conclusion
> that Cisco had extended the standard, and I am currently trying to track
> this down also.  Any information you've discovered would be appreciated.

All I have is this link which someone else on the NSP list posted from CCO:

  http://www.cisco.com/en/US/products/sw/iosswrel/ps1834/products_feature_guide09186a00800e9763.html#xtocid5

Here are some clippings from it.  Cisco seems to have added this
opcode as part of the feature "HSRP Support for ICMP Redirects":

   Passive HSRP Router Advertisements

   Passive HSRP routers send out HSRP advertisement messages both
   periodically, and when entering or leaving the passive state. Thus, all
   HSRP routers can determine the HSRP group state of any HSRP router on the
   network. These advertisements inform other HSRP routers on the network of
   the HSRP interface state:

   Dormant - interface has no HSRP groups, single advertisements sent once when
   last group is removed
   Passive - interface has at least one non-active group and no active groups,
   advertisements sent out periodically
   Active - interface has at least one active group, single advertisement sent
   out when first group becomes active