D-Link DGS-6600-48TS Configuration Guide - Page 251

Volume 4-Layer 3 Configurations / Chapter 25-IPv6 Basics Chapter Overview NA & NS message Router RA message RS - provide prefix with prefer time and valid time - provide operation parameters Figure 25-1 Router Discovery & Automatic Parameter Configuration In IPv4 a default router is normally manually configured. In IPv6 the default router on the host's side will be automatically learned. The router constantly sends out an RA message. The host will learn the router when it receives the RA. To speed up the discovery process, the host can send out the RS message and wait for the immediate RA message response from the router. Normally the host will send out an RS message whenever an IP interface comes up. From the RA message, the host also automatically configures a variety of configuration parameters. The following describes the purpose of these parameters. When the host receives RA messages from multiple routers it accepts all received information. However, when received information for a specific parameter (e.g., Link MTU) or an option (e.g., Lifetime on a specific Prefix) differs from information received earlier, and if the parameter/option can only have one value, the most recently received information is considered authoritative. RA Auto configure Router Auto configure Parameters , reachable time, hop limit, mtu, retransmit time. Auto configure addresses Assign prefix with prefer time and valid life time RS Figure 25-2 DGS-6600 Configuration Guide 251