Search results
Results from the WOW.Com Content Network
Each routing protocol contains loop-avoidance mechanisms, but the information needed for loops to be avoided is lost when routes are redistributed. For example, a distance-vector routing protocol may prevent loops by the "split-horizon" rule; that is to say, if a router learns a route from a particular interface it will not re-advertise the ...
Route table showing internet BGP routes . In computer networking, a routing table, or routing information base (RIB), is a data table stored in a router or a network host that lists the routes to particular network destinations, and in some cases, metrics (distances) associated with those routes.
In computer networking, policy-based routing (PBR) is a technique used to make routing decisions based on policies set by the network administrator.. When a router receives a packet it normally decides where to forward it based on the destination address in the packet, which is then used to look up an entry in a routing table.
Cisco literature refers to Enhanced Interior Gateway Routing Protocol (EIGRP) as a "hybrid" protocol, [12] despite the fact it distributes routing tables instead of topology maps. However, it does synchronize routing tables at start-up as OSPF does and sends specific updates only when topology changes occur.
For example, on Cisco routers, routes issued by the Open Shortest Path First routing protocol have a lower default administrative distance than routes issued by the Routing Information Protocol. This is because, by default on Cisco routers, OSPF has a default administrative distance of 110 and RIP has a default administrative distance of 120.
Example of setting up EIGRP on a Cisco IOS router for a private network. The 0.0.15.255 wildcard in this example indicates a subnetwork with a maximum of 4094 hosts—it is the bitwise complement of the subnet mask 255.255.240.0.
The specific characteristics of routing protocols include the manner in which they avoid routing loops, the manner in which they select preferred routes, using information about hop costs, the time they require to reach routing convergence, their scalability, and other factors such as relay multiplexing and cloud access framework parameters.
IP forwarding algorithms in most routing software determine a route through a shortest path algorithm. In routers, packets arriving at an interface are examined for source and destination addressing and queued to the appropriate outgoing interface according to their destination address and a set of rules and performance metrics.