RFC 3442 (rfc3442) - Page 3 of 9
The Classless Static Route Option for Dynamic Host Configuration Protocol (DHCP) version 4
Alternative Format: Original Text Document
RFC 3442 Classless Static Route Option for DHCPv4 December 2002 This document also uses the following terms: "DHCP client" DHCP client or "client" is an Internet host using DHCP to obtain configuration parameters such as a network address. "DHCP server" A DHCP server or "server" is an Internet host that returns configuration parameters to DHCP clients. "link" Any set of network attachment points that will all receive a link-layer broadcast sent on any one of the attachment points. This term is used in DHCP because in some cases more than one IP subnet may be configured on a link. DHCP uses a local- network (all-ones) broadcast, which is not subnet-specific, and will therefore reach all nodes connected to the link, regardless of the IP subnet or subnets on which they are configured. A "link" is sometimes referred to as a broadcast domain or physical network segment. Classless Route Option Format The code for this option is 121, and its minimum length is 5 bytes. This option can contain one or more static routes, each of which consists of a destination descriptor and the IP address of the router that should be used to reach that destination. Code Len Destination 1 Router 1 +-----+---+----+-----+----+----+----+----+----+ | 121 | n | d1 | ... | dN | r1 | r2 | r3 | r4 | +-----+---+----+-----+----+----+----+----+----+ Destination 2 Router 2 +----+-----+----+----+----+----+----+ | d1 | ... | dN | r1 | r2 | r3 | r4 | +----+-----+----+----+----+----+----+ In the above example, two static routes are specified. Lemon, et. al. Standards Track
