Routing Technologies
Routing types and Routing Protocols
Communication is incredibly important in today’s technological world. And much of these communications is happens through a very complex web of networks throughout the world. Taking information from one point to another point is called networking. So it’s very important to have the knowledge of routing process and the types of routing protocols we need to use. Routing makes the internet possible.
To begin to start about Routing Technologies we have to know about what is routing? and what taking place when a router routes a packet? We can simply define routing is the process of forwarding packets between different networks. In the real world, we are using a lot of devices to communicate such as a smartphone, laptop and so on .. All the devices have the network card some are having two network card to communicate. If our communication is the same subnet we don’t need to use a router but if we want to communicate with different subnetworks there is need of default gateway to pass the packets between them that’s what router does.
Basic components needed to route:
01)Routable Packet (IPv4, IPv6 etc)
02)Network address
03)Subnet mask
04)Next Hop
05)Metric
In the below diagram lets see what happens to the packet!
If PC-PT wants to send a packet to Server- PT it looks the Destinations address and identifies the address is not on its network then it sends to its default gateway! (If it’s on the same network switch pass the packet to the destination) Here Layer 2 header contains source mac address (PC-PT) and destination mac address which is the router’s fast ethernet 0/0 mac address. Once the router receives the packet it sees the destination IP address and it looks its directly connected networks and the destination network is not connected then it passes the packet to the next router. Throughout the process layer 3 address won’t be changed only layer 2 address change.
Static Routing: This type of routing is typically used in the small network. In Static Routing administrator manually inputs all routing table information. There is no dynamic failure it’s preferred over dynamic routing because of lower administrative distance.
Dynamic Routing: Protocols can dynamically respond to changes in the network. Routing protocols help to learn about the routing table of the neighbor router and remote network. Routing protocol has the responsibility for maintaining the routing table. There are two types of a routing protocol.
Interior Gateway protocol: Protocol that works within the same Autonomous System Number.Example:- OSPF(Open Shortest Path First), EIGRP(Enhanced Interior Gateway Routing Protocol), RIP(Routing Information Protocol)
Exterior Gateway protocol: Protocol that interconnects multiple Autonomous System Numbers.Example:- BGP(Border Gateway Protocol)
