Convergence is the state of a network when all
routers in that
network share the most updated
routing tables.
Routing Protocols, such as
RIP,
EIGRP, and
IGRP, are responsible for
broadcasting routing tables, which makes these protocols the cause of Convergence and Convergence Time.
When a change in one or more router's routing table, all other routers have to be informed of the change. The time it takes until all routers have updated information about the new/obsolete
route is called the Convergence Time