[c-nsp] OFF TOPIC: EIGRP Multicast Flow timer

[omar parihuana]

Hi guys,

Recently, I was reviewing about EIGRP, and found one question that
unfortunately Cisco web page don't help me, after check in google I found
the follow explanation (extracted of cisco-nsp archives):

"After a pair of routers become neighbors, they will send routing updates
(and other packets) to one another using a reliable multicast scheme. For
example, if router one has a series of packets which must be transmitted to
routers two, three, and four, such as a routing table update, it will send
the first packet to the EIGRP multicast address, 224.0.0.10, and wait for a
acknowledgment from each of it's neighbors on it's ethernet interface (in
this case routers two, three, and four). Let's assume that routers two and
four do answer, but router three does not.
Router one will wait until the multicast flow timer expires on the ethernet
interface, then send out a special packet, a sequence tlv, telling router
three not to listen to any further multicast packets from router one, then
will continue transmitting the remainder of the update packets as multicast
to all other routers on the network. The sequence tlv indicates an
out-of-sequence multicast packet. Those routers not listed in the packet
enter conditional receive (CR) mode and continue listening to multicast.
While there are some routers in this mode, the conditional receive bit will
be set in multicast packets. In this case, router one will send out a
sequence tlv with router three listed, so routers two and four will continue

listening to further multicast updates".  *From:* Steve Pickavance (*
spickava at cisco.com*<spickava at cisco.com?Subject=RE:%20Strange%20trafic%20to%20224.0.0.10&In-Reply-To=%3CNDBBJPIPGLNHHMHIAJFJGEKDJCAA.spickava at cisco.com%3E>
)

However I have some questions, in accordance to explanation above: if router
one send to router three a TLV telling not listen to any further multicast
packet, how router three learn new updates? special unicast?  of course
router three is UP and working fine again. Could you give more details about
that?

Thanks in advanced...

Rgsd

-- 
Omar E.P.T
-----------------
Certified Networking Professionals make better Connections!