Understanding Open Shortest Path First
(OSPF) Basics
Open Shortest Path First (OSPF) is an open standards routing protocol that has been implemented
by a wide variety of network vendors, including Cisco.
This works by using the Dijkstra algorithm. First a shortest path tree is constructed, and
then the routing table is populated with the resulting best paths. OSPF converges quickly,
although perhaps not as quickly as EIGRP, and it supports multiple, equal-cost routes to the
same destination. Like EIGRP, it does support both IP and IPv6 routed protocols.
OSPF provides the following features:
Consists of areas and autonomous systems
Minimizes routing update traffic
Allows scalability
Supports VLSM/CIDR
Has unlimited hop count
Allows multivendor deployment (open standard)
Table 4.9 describes the characteristics of the RIP and OSPF protocols discussed thus far.