Routing and types of routing
Routing is a process of forwarding packets from one network to another network in an optimal way. It happens in Layer3 or network layer and it performed by a dedicated device called router. Routing process will happens based on the routing tables. It was specified by a network administrator or a routing protocols. Routing tables are acts as a map for routing, these tables are typically having the information about the packet’s destination, next hop and when forwarding packets to next hop or final destination of a packet the device’s network Interface should be used. These tables are typically will contain the information regarding packet’s destination, next hop and the network interface (while forwarding packets to next hop or final destination the device’s network Interface should be used).
The routing table can be built in two ways,
In Static Routing, the routing table will have created and maintained manually by a network administrator. In this routing, each router should be configured for connectivity across the networks. Static routing gives control over the routing but not possible to configure for larger networks.
Pros of Static Routing
i)In static routing the routers will not share static routes with each other, so the resources(CPU, RAM, Bandwidth) usage less.
ii)The administrator has a control on routing
Cons of Static Routing
i)This is not fault tolerant, if one router goes down the connectivity will be loss
ii)Infrastructure changes must be manually updated in the routing table
iii)Not possible for large networks
In Dynamic Routing, the routing table is created and maintained automatically by routing protocols which was running on the router. All Infrastructure changes will be automatically updated by routing protocols.
Routing Protocols: Dynamically builds the networks, topology and routing tables (Ex. RIP, EIGRP, OSPF, IGRP)
Routed Protocols: It provides the logical address to devices and routes the packet (Ex. IP, IPX)
Pros of Dynamic Routing
i)Fault tolerance (if one link goes down, the routing path will be automatically adjusted)
ii)Infrastructure changes are automatically updated
Cons of Dynamic Routing
i) The routing updates are shared between the routers, that will be consuming more bandwidth. Routing protocols will utilize more CPU and RAM
ii)Administrator Doesn’t have Control on routing. The creation of the best path for routing depends on routing protocols.