Comparing Distance Vector, Link State, and Hybrid routing

There are three types of dynamic routing: distance vector, link state, and hybrid. Each routing uses a different approach and algorithm to calculate the best path for every subnet available in the network.

Each routing type has advantages and disadvantages. When selecting a routing type for a network, you need to consider and compare many factors and elements. The following table compares all three types and lists their differences.

Feature Distance vector Link state Hybrid
Example protocols RIP, RIPv2 OSPF EIGRP, BGP
Metrics Hop count Cost Composite of bandwidth and delay
Things it uses to calculate the best route The number of routers (hops) between a router and the destination subnet The sum of all interface cost settings for all links in a route Route’s slowest link and the cumulative delay associated with each interface in the route
Convergence Convergence is slow. Convergence is moderate. Convergence is fast.
Routing update method It broadcasts routing updates. All routers receive routing updates. It multicasts routing updates. Only routers running the same routing protocol receive and process the routing updates. It multicasts routing updates. Only routers running the same routing protocol receive and process the routing updates.
Routing update interval It broadcasts all routing updates at a fixed interval. If anything changes (such as a link goes down or comes up), other routers will learn about it at the next routing update. It supports trigger updates. If anything changes, it immediately updates other routers about it. It also supports trigger updates. It updates other routers about changes immediately.
VLSM supports It supports only classful routing. It supports classless (VLSM) routing. It also supports classless (VLSM) routing.
Algorithm It uses the Bellman-Ford algorithm to calculate the best path. It uses the Dijakstra’s algorithm to calculate the shortest path. It uses the DUAL algorithm to calculate the shortest and fastest path.
Bandwidth Since it periodically broadcasts all routing updates, it consumes more bandwidth. It consumes less bandwidth. It shares the routing updates only when required or if something changes. It also consumes less bandwidth.
Routing update contains Routing updates contain all entries from the routing table. Routing updates contain only changes. Routing updates contain only changes.
Supported network size It supports only small-sized networks. It supports all types of networks. It supports all types of networks.
Maximum hops a link can have 15 Unlimited Unlimited
Network knowledge It knows only about the directly connected routers. It knows about all network routers. It knows about all network routers.
Use of hardware resources It consumes the least CPU and RAM. It consumes the most CPU and RAM among these methods. It consumes more CPU and RAM than distance vector routing but less than link state routing.
Load balancing It does not support load balancing. It supports load balancing. It supports load balancing.
Dis-contiguous network supports It does not support dis-contiguous networks. It supports contiguous networks. It also supports contiguous networks.

ComputerNetworkingNotes CCNA Study Guide Comparing Distance Vector, Link State, and Hybrid routing