![](/images/backgrounds/293017/hp-v1910-users-manual-120219290x1.png)
Option 82 is the relay agent option in the option field of the DHCP message. It records the location information of the DHCP client. When a DHCP relay agent or DHCP snooping device receives a client’s request, it adds Option 82 to the request message before forwarding the message to the server.
The administrator can locate the DHCP client to further implement security control and accounting. The Option 82 supporting server can also use such information to define individual assignment policies of IP address and other parameters for the clients.
Option 82 involves at most 255
Option 82 has no unified definition. Its padding formats vary with vendors.
By default, the normal padding format is used on the device. You can specify the code type for the
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0 | 7 |
| 15 | 23 | 31 |
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| Length (0x06) | Circuit ID type (0x00) | Length (0x04) | ||
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| VLAN ID |
| Interface number | ||
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∙RFC 2131, Dynamic Host Configuration Protocol
∙RFC 2132, DHCP Options and BOOTP Vendor Extensions
∙RFC 1542, Clarifications and Extensions for the Bootstrap Protocol
∙RFC 3046, DHCP Relay Agent Information Option
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