TABLE OF CONTENTS The ND protocol packets use the general ICMPv6 message format. Each message begins with the ICMPv6 message type, the message code, the Checksum field, and is followed by the message body as illustrated in Figure 5-6. ICMPv6 is discussed in detail in Chapter 4.
In the explanation to follow, source address refers to the Source Address field in the IPv6 packet header, and destination address refers to the Destination Address field in the IPv6 header as shown in Figure 5-6. The message body is composed of various fields depending on the packet type. Each ND packet may contain a number of option fields.
The propagation of ND protocol packets is limited within a single link. This is enforced by using the hop limit value of 255 for all ND packets. Since ND packets that originate from off-link nodes have hop limit values less than 255, the receiving node can reject such packets by checking the Hop Limit field.
A host sends Router Solicitation messages to the all-routers multicast address ff02::2 (Section 2.5.3). Figure 5-7 details the message format. The source address can be either one of the addresses of the sending interface or the unspecified address if the transmitting interface has not been given any addresses.
The Type field has the value 133. The Code field has the value 0. The checksum field contains the ICMPv6 checksum value. The Reserved field must...
