Convergence is a state when all router’s routing table are at a state of consistency. The convergence time is the time it takes to routers to share information, calculate the optimal path, and update their Routing Table.
Convergence
-
Open Shortest Path First (OSPF)
OSPF is a #Layer 3 #classless #Link-State Routing Protocol developed by Internet Engineering Task Force (IETF)# where its metric is an arbitrary value called cost (defined by RFC 2328). In Cisco, the cost calculated using bandwidth. It is secure, scalable and provides fast Convergence#. It supports both IPv4 and IPv6. The implementation of OSPF varies from vendor to vendor.
-
Link-State Routing Protocol
It is best used in a Hierarchical Network and fast convergence# of the network is crucial.
-
Distance Vector Routing Protocol
It is best used simple and flat network or specific types of networks such as hub-and-spoke networks#. If the worst-case Convergence# times in the network is not a concern, which is the worst disadvantage of using a Distance Vector Routing Protocol.