Interrouter

Interrouter is a term used to describe the set of mechanisms, devices, and interfaces that enable routing between routers or between routing domains in a computer network. It encompasses the physical links, control planes, and policies that connect routers to form larger networks, whether within a single organization or across the Internet.

Function and scope

Interrouter connectivity handles the exchange of routing information, the selection of paths, and the forwarding of packets between routers. Within a network, routing protocols such as OSPF or IS-IS manage routes inside a domain (intra-domain routing), while protocols like BGP manage routes between domains (inter-domain routing). Interrouter components include the links that carry control and data traffic, the router interfaces, and the software or hardware that runs routing protocols and policy enforcement.

Components and operation

Key elements include physical or logical interrouter links (fiber, copper, wireless), routing adjacencies between neighbor routers, and the control plane software that runs routing protocols. Routers exchange reachability information, apply local policies, and advertise chosen routes to peers. In large networks, mechanisms such as route reflectors, route servers, or multi-homed arrangements help manage scalability and reliability of interrouter connectivity.

Security and reliability

Interrouter networks rely on session authentication, route filtering, and prefix filtering to prevent misconfigurations and attacks. Measures such as cryptographic authentication, access control, and route protection (for example, RPKI) enhance trust. Redundancy and diverse peering paths improve resilience against failures or outages.

See also

Border Gateway Protocol, OSPF, IS-IS, inter-domain routing, Internet backbone, peering.