Geocast refers to the delivery of information to a group of destinations in a network

Computer network

A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....

 identified by their geographical locations. It is a specialized form of multicast

Multicast

In computer networking, multicast is the delivery of a message or information to a group of destination computers simultaneously in a single transmission from the source creating copies automatically in other network elements, such as routers, only when the topology of the network requires...

 addressing used by some routing protocols

Ad hoc routing protocol list

An ad-hoc routing protocol is a convention, or standard, that controls how nodes decide which way to route packets between computing devices in a mobile ad hoc network ....

 for mobile ad hoc networks.

Geographic addressing

A geographic destination address is expressed in three ways: point, circle (with center point and radius), and polygon (a list of points, e.g., P(1), P(2), …, P(n–1), P(n), P(1)). A geographic router (Geo Router) calculates its service area (geographic area it serves) as the union of the geographic areas covered by the networks attached to it. This service area is approximated by a single closed polygon. Geo Routers exchange service area polygons to build routing tables. The routers are organized in a hierarchy.

Applications

Geographic addressing and routing has many potential applications in geographic messaging, geographic advertising, delivery of geographically restricted services, and presence discovery of a service or mobile network participant in a limited geographic area.

External links

• RFC 2009
• A Survey of Geocast Routing Protocols