me node used previously when registering a multicast address for listening. This address is sent from an undefined IPv6 address in order not to pollute Neighbor Caches of other nodes on the link, in case there were conflicts. In Figure 3.27 we have opened the IPv6 packet to show the next header field value of ICMPv6, and a more typical hop limit of '255'. The ICMPv6 message type is of course "Neighbor Solicitation'. The 'code' field is zero, as always for this message type. The 'target' address field is the key here and it shows what is the exact IPv6 address that the host is soliciting for. It may be possible that a link has multiple nodes that have the No., Time Source Destination Protocol Info 5 23.1693 ff02::16 ICMPV6 Multicast Listener Report Message v2 6 23.7791 ff02::1:fff1:8d0d ICMPV6 Neighbor solicitation 7 24.5386 fe80::230:5ff:fe7f:fd5f ff02::1 ICMPV6 Router advertisement 8 24.6088 ff02::1:fff1:8d0d ICMPV6 Neighbor solicitation 9 24.7789 fe80::ba27:ebff:fef1:8d0d ff02::2 ICMPV6 Router solicitation 11 25.1889 fe80::ba27:ebff:fef1:8d0d ff02::16 ICMPV6 Multicast Listener Report Message v2 12 27.7387 fe80::230:5ff:fe7f:fd5f ff02::1 TCMPV6 Router advertisement Frame 6 (78 bytes on wire, 78 bytes captured) Ethernet II, Src: b8:27:eb:f1:8d:0d (b8:27:eb:f1:8d:0d) Dst: IPV6-Neighbor-Discovery_ff:f1:8d:0d Internet Protocol Version 6 Version: 6 Traffic class: 0x00 Flowlabel: 0x00000 Payload length: 24 Next header: ICMPV6 (0x3a) Hop limit: 255 Source address: :: Destination address: ff02::1:fff1:8d0d Internet Control Message Protocol v6 Type: 135 (Neighbor solicitation) Code: 0 checksum: 0xbc01 [correct] Target: fe80::ba27:ebff:fef1:8d0d Figure 3.27 Example: initiating DAD for an IPv6 link-local address. Introduction to IPv6 same lowest 24 bits of the address - in this case f1:8d:0d - and hence multiple nodes might receive the solicitation. However, only one host could have the full solicited IPv6 address. Also from here we can for the first time see what the address the host is planning to configure for itself. I