R0106-HP MSR Router Series Layer 3 - IP Services Configuration Guide(V7)

253
Figure 98 Trusted and untrusted ports
Feature and hardware compatibility
This feature is supported only on the following models:
MSR routers that hold an Layer 2 switching module.
HP implementation of Option 18 and Option 37
Option 18 for DHCPv6 snooping
Option 18, also called the interface-ID option, is used by the DHCPv6 relay agent to determine the
interface to use to forward RELAY-REPLY message.
In HP implementation, the DHCPv6 snooping device adds Option 18 to the received DHCPv6 request
message before forwarding it to the DHCPv6 server. The server then assigns IP address to the client
based on the client information in Option 18.
Figure 99 Option 18 format
Figure 99 shows the Option 18 fields:
• Option code—Option code.
• Option length—Size of the option data.
• Port index—Port that receives the DHCPv6 request from the client.