> From: Or Gerlitz > Sent: Thursday, February 15, 2007 4:25 AM > To: Roland Dreier; Hal Rosenstock; openib > Subject: [openib-general] IPv6 multicast address per NIC > > Hi, > > I see that when IPv6 is enabled in the kernel, the stack joins for a > --dedicated-- multicast group per each interface. Can anyone here supply > me with a pointer to where this is defined, doing a quick look on rfc > 3307 did not provide an answer. > RFC 2373 defined an IPv6 Solicited Node multicast address which is based on the IPv6 address of the Node. Each node supports a unique multicast (in addition to the assorted multicast addresses for all nodes, all routers, etc).
>From RFC 2373: Solicited-Node Address: FF02:0:0:0:0:1:FFXX:XXXX The above multicast address is computed as a function of a node's unicast and anycast addresses. The solicited-node multicast address is formed by taking the low-order 24 bits of the address (unicast or anycast) and appending those bits to the prefix FF02:0:0:0:0:1:FF00::/104 resulting in a multicast address in the range FF02:0:0:0:0:1:FF00:0000 to FF02:0:0:0:0:1:FFFF:FFFF For example, the solicited node multicast address corresponding to the IPv6 address 4037::01:800:200E:8C6C is FF02::1:FF0E:8C6C. IPv6 addresses that differ only in the high-order bits, e.g. due to multiple high-order prefixes associated with different aggregations, will map to the same solicited-node address thereby reducing the number of multicast addresses a node must join. A node is required to compute and join the associated Solicited-Node multicast addresses for every unicast and anycast address it is assigned. Todd Rimmer _______________________________________________ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general