1.2 Related Work

There are several Internet protocols and related mechanisms that address some parts of the dynamic host configuration problem. The Reverse Address Resolution Protocol (RARP) [10] (through the extensions defined in the Dynamic RARP (DRARP) [5]) explicitly addresses the problem of network address discovery, and includes an automatic IP address assignment mechanism. The Trivial File Transfer Protocol (TFTP) [20] provides for transport of a boot image from a boot server. The Internet Control Message Protocol (ICMP) [16] provides for informing hosts of additional routers via "ICMP redirect" messages. ICMP also can provide subnet mask information through the "ICMP mask request" message and other information through the (obsolete) "ICMP information request" message. Hosts can locate routers through the ICMP router discovery mechanism [8].

BOOTP is a transport mechanism for a collection of configuration information. BOOTP is also extensible, and official extensions [17] have been defined for several configuration parameters. Morgan has proposed extensions to BOOTP for dynamic IP address assignment [15]. The Network Information Protocol (NIP), used by the Athena project at MIT, is a distributed mechanism for dynamic IP address assignment [19]. The Resource Location Protocol RLP [1] provides for location of higher level services. Sun Microsystems diskless workstations use a boot procedure that employs RARP, TFTP and an RPC mechanism called "bootparams" to deliver configuration information and operating system code to diskless hosts. (Sun Microsystems, Sun Workstation and SunOS are trademarks of Sun Microsystems, Inc.) Some Sun networks also use DRARP and an auto-installation mechanism to automate the configuration of new hosts in an existing network.

In other related work, the path minimum transmission unit (MTU) discovery algorithm can determine the MTU of an arbitrary internet path [14]. The Address Resolution Protocol (ARP) has been proposed as a transport protocol for resource location and selection [6]. Finally, the Host Requirements RFCs [3, 4] mention specific requirements for host reconfiguration and suggest a scenario for initial configuration of diskless hosts.