Tag: route

Difference between defining static routes with next-hop address or exit interface

For a long time I was confused about this. It was not clear to me what is the difference between setting the static route using next hop interface IP address instead of exit interface (outgoing interface) syntax. It seemed that both methods are the same and that you have basically two different ways to define static route on specific device for no particular reason.

It was not clear to me why would someone do this kind of option on networking device OS if there were no reason for doing so. In other words I was strongly convinced that there must be some difference between two configs and learning more detail about the process of routers recursive searches and Proxy ARP function did answer all my doubts.

So now is time to put it all on paper for you to see it:

You can define static route like this:

R1(config)#ip route 10.0.0.0 255.255.255.0 10.10.2.1

This means that all packets from R1 with destination address from 10.0.0.0/24 subnet will be forwarded out the interface leading to next hop device with 10.10.2.1 address on its interface.

Other way is to define the same static route like this:

R1(config)#ip route 10.0.0.0 255.255.255.0 fastEthernet 0/0

If fastEthernet 0/0 is the interface on R1 router that leads to next hop router with best path to 10.0.0.0/24

What’s the difference, which is better?

If you use next-hop address, you can conclude that your router will not have the information which interface must he use in order to route those packets out towards destination. R1 must then find an interface that is having 10.10.2.1 on other side.

BGP – Border Gateway Protocol

BGP is the Internet routing protocol. He is making the Internet work.

BGP protocol performs actions by maintaining IP networks table for the biggest network in the world – The Internet. The BGP protocol, as a code of behavior, supported core routing decisions over the Internet.  Instead of using traditional IGP (Interior Gateway Protocol) metrics, BGP protocol relies upon available path, network guidelines and rule-sets for routing decision making purposes. And just for this feature, it is sometimes expressed as a reachability protocol. The main idea behind the BGP creation was to replace the EGP (Exterior Gateway Protocol) to permit a complete decentralized routing. NSFNET backbone is the best example of a decentralized system.

Routing – Static and Dynamic routes – What is route?

What is Routing and what Static and Dynamic routes means?
Routing packetsIn the theory of networking, we must mention the concept of routing to help explain how networking works and what exactly is networking. Simply, the word “routing” is meant by map-reading or direction-finding. But in the computer’s world, it is a system for forwarding the information from some network node to another over an internetwork such as from a starting point (source) to its ending point (destination).