Dell Force10 S55T S55 Configuration Guide FTOS 8.3.5.3 - Page 354

www.dell.com | support.dell.com IPv6 Neighbor Discovery c e s IPv6 NDP is supported on platforms Neighbor Discovery Protocol (NDP) is a top-level protocol for neighbor discovery on an IPv6 network. In lieu of ARP, NDP uses "Neighbor Solicitation" and "Neighbor Advertisement" ICMPv6 messages for determining relationships between neighboring nodes. Using these messages, an IPv6 device learns the link-layer addresses for neighbors known to reside on attached links, quickly purging cached values that become invalid. With ARP, each node broadcasts ARP requests on the entire link. This approach causes unnecessary processing by uninterested nodes. With NDP, each node sends a request only to the intended destination via a multicast address with the unicast address used as the last 24 bits. Other hosts on the link do not participate in the process, greatly increasing network bandwidth efficiency. Figure 17-3. NDP Router Redistribution Router C Send a Packet to Network 2001:db8::1428:57ab Router A Local Link Packet Destination (2001:db8::1428:57ab) ICMPv6 Redirect (Data: Use Router C) Packet Destination (Destination 2001:db8::1428:57ab) Network 2001:db8::1428:57ab Router B IPv6 Neighbor Discovery of MTU packets With FTOS 8.3.1.0, you can set the MTU advertised through the RA packets to incoming routers, without altering the actual MTU setting on the interface. The ip nd mtu command sets the value advertised to routers. It does not set the actual MTU rate. For example, if ip nd mtu is set to 1280, the interface will still pass 1500-byte packets, if that is what is set with the mtu command. QoS for IPv6 e IPv6 QoS is supported on platforms 354 | IPv6 Addressing