Glossary of Terms
Terms used in descriptions throughout this document are defined
below:
- adjacency
- A relationship formed between selected neighboring routers for
the purpose of exchanging routing information. Not every
pair of neighboring routers becomes adjacent.
- autonomous system
- A set of routers under a single technical administration, using
an interior gateway protocol and common metrics to route
packets within the AS, and using an exterior gateway protocol
to route packets to other ASs. Since this classic
definition was developed, it has become common for a single AS
to use several interior gateway protocols and sometimes several
sets of metrics within an AS. The use of the term Autonomous
System stresses that even when multiple igps and metrics are
used, the administration of an AS appears to other ASs to
have a single coherent interior routing plan and presents a
consistent picture of what networks are reachable through
it. The AS is represented by a number between 1 and 65534,
assigned by the Internet Assigned Numbers Authority.
- BGP
- Border Gateway Protocol
- One of a class of exterior gateway
protocols, described in more detail in the BGP section of the Protocol Overview.
- cost
- An OSPF metric. See metric.