Figure 78 Trusted and untrusted ports
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 79 Option 18 format
Figure 79
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.
•
VLAN ID—ID of the outer VLAN.
•
Second VLAN ID—ID of the inner VLAN.
•
DUID—DUID of the DHCPv6 client.
•
192