DHCP proxy definition
A DHCP, or Dynamic Host Configuration Protocol, proxy, refers to a network device or service that acts as an intermediary between DHCP clients and DHCP servers. It is used to help the server and the client communicate without exposing the server’s real IP address.
See also: dhcp, caching proxy, http proxy, transparent proxy, proxy surfing
How does the DHCP proxy work?
- DHCP discovery. A DHCP client sends out a discovery message as a broadcast, intended to find a DHCP server and obtain IP configuration information.
- DHCP proxy relay. The DHCP proxy intercepts the message and relays it to one or more DHCP servers.
- DHCP server response. The DHCP server processes the message, assigns an IP address and other network configuration information, and sends the message back to the proxy.
- Proxy client response. The proxy relays the message back to the DHCP client which obtains the configuration parameters.
- DHCP acknowledgment. The client uses the DHCP proxy to send another message to the server. Then, the server sends the message back, confirming the lease of the IP address.
- Proxy client configuration. The proxy again relays the DHCP acknowledgment message to the client that can now apply the configuration details such as the assigned IP address, subnet mask, default gateway, and DNS server information.