OSPF Protocol CISCO Packet Tracer Example
09.05.2020 00:32
#OSPF #CISCO #PACKETTRACER #BILGISAYARAGLARI
OSPF Protocol CISCO Packet Tracer Example
What Is OSPF Protocol?
English Open Shortest Path First, meaning "Priority to the shortest path," OSPF is a protocol used to automatically recognize routers in a TCP / IP network. OSPF routing is a widely used method such as RIP for intra-AS routing on the Internet. OSPF is mainly used in the upper layers of internet service providers (ISP). The first letter O in the word OSPF indicates that the routing protocol conditions are clear (for example, as opposed to Cisco's EIGRP protocol). It is the second most current version of OSPF.
How does it work?
OSPF is thought after RIP and has many advanced features. It is basically a link-state protocol that uses overflow of link-state (English: link-state) and Dijkstra's shortest path algorithm. Together with OSPF, a router creates the entire topological map of the network. The router then uses Dijkstra's shortest path algorithm to get the shortest path tree to all networks locally, determining itself as root in this tree. Special connection costs between routers are set by the network administrator. The administrator can set all connection costs to 1, so that he can manage minimum-hop routing, or choose the connection loads by traffic or bandwidth. OSPF is not concerned with connection costs, instead it only offers a protocol to identify the lowest cost paths that can be achieved with the given set of connection costs. With OSPF, a router broadcasts routing information to all other routers, not just its neighbors.
Difference from RIP?
OSPF works in a similar way to RIP, so routers exchange information about the networks they can access.
On the other hand, OSPF does not send how many steps it can reach a network, but how quickly (or at what speed) it can reach a network. Therefore, the problem of counting forever, which can be seen in the RIP, is eliminated.
In addition, OSPF has four different network ranks (English Backbone area, Stub area, Totally stubby area and Not-so-stubby area).
Similarly, routers can be ranked:
- Interregional routers
- Autonomous network end router
- Autonomous network internal router
- Backbone network router
- Selected router
- Selected backup router