Background

Any node in an IP network needs a valid IP address to be able to participate in routing and regular data communication. It is the IP address that uniquely identifies the node as an endpoint in network communication.

There are several ways to acquire an IP address. For wired networks, the two most common ways are either static configuration, or by the use of the Dynamic Host Configuration Protocol(DHCP)[30]. A static configuration can simply be that the node has been given a valid address by a system administrator and will always use this address. For a network with many nodes, this is not scalable. The DHCP framework is based upon a client-server model. This architecture leads to a single point of failure. If the DHCP server is out of reach the service is not available. DHCP clients also uses broadcasts to emit requests. For a MANET, both these factors are troublesome. MANETs should favor distributed operation as opposed to centralized designs as those used in DHCP. Broadcasting in a MANET will not reach all nodes in the network unless special broadcast extensions or other mechanisms are used. So DHCP is not a well suited solution for IP address auto configuration in MANETS.

Andreas 2004-07-29