A distance-vector routing protocol in data networks resolves the best route for data packets on the basis of distance. Distance vector routing protocols would be measuring the distance by the number of routers which a packet has to clear, one router could be counted as one hop. Some distance vector protocols would be also taken into account network latency as well as other factors that would be influencing traffic on a given route. To determine the best route across a network, routers, on which a distance vector protocol would be implemented, exchange information with one another, basically, the routing tables plus hop counts for destination networks and perhaps other traffic information. Distance vector routing protocols also necessitate that a router informs its neighbors of network topology would be changing periodically.
The term distance vector would be referring to the fact that the protocol would be manipulating vectors (arrays) of distances to other nodes in the network. The distance vector algorithm was originally the ARPANET routing algorithm and it was implemented more widely in LANs (Local Area Networks) with the RIP (Routing Information Protocol).
If you’re working towards your CCNP, CCIP, or CCDP certifications then the BSCI – Building Scalable Cisco Internetworks exam (642-901) applies to all three of these certifications. The BSCI exam is all about advanced IP addressing and routing and it tests your knowledge and skills on implementing scalability for Cisco Integrated Services Routers (ISR) connected to LANs and WANs. In case you wish to study for the Cisco Certification Courses, you should opt for the SPOTO Club to ensure your success.
Some of the topics that the BSCI exam covers include:
- Advanced IP addressing
- Routing principles
- Multicast routing
- Manipulating routing updates
- Configuring basic BGP
- Configuring EIGRP, OSPF, and IS-IS
Let’s begin with a description of the operational principles of the two routing classes and afterward, I’ll get into the details on their actual operation and design.
Why Two Dynamic Routing Protocol Classes?
There would be different routing classes which are available for providing a more spherical solution packet. Different networks would be having special individual needs and different routing protocols would have been designed to meet the individual needs of these networks. There is no straightforward answer on the right routing protocol to utilize.
Distance Vector Routing Protocols
Distance Vector routing protocols would be based on their decisions on the best path to a given destination on the basis of distance. Distance is usually measured in hops, though the distance metric might be a delay, packets lost, or somewhat similar. If the distance metric is considered as hop, then each time a packet goes through a router, a hop would be considered to have traversed. The route with the least number of hops to a given network would be concluded to be the best route towards that network.
Link State Routing Protocols
Link state protocols are also considered to be the shortest-path-first protocols. Link state routing protocols would be having a complete picture of the network topology. Hence they would know more about the whole network than any distance vector protocol.
Three separate tables would be created on each link state routing enabled router. One table is considered to be utilized to hold details about neighbors which are connected directly, one is utilized to hold the topology of the entire internetwork and the last one is to be utilized for holding the actual routing table. Link state protocols would be sending information about directly connected links to all the routers in the network.
So, you might have gained the basic knowledge of the Dynamic Routing Principal. If you wish to have more detailed knowledge do join the SPOTO Club, for better results.