Difference b/w CIDR & Summarization

[9826024006]

HI All,
please let me know what is the difference between CIDR & Summarization??

its very urgent please help me out

Thanks

Ninja

 

[headlessringmaster]

The basics:

CIDR - "Classless" InterDomain Routing -
This refers to the ability to consider a subnet address with a mask other than what its class defines. So, the address 1.1.1.1 is a class A address, and therefore, would naturally have a mask of 255.0.0.0. CIDR allows you to break up subnets so that you might have a subnet 1.1.1.0 mask 255.255.255.0. A routing protocol that allows CIDR can route between/to these more specific subnets.

Summarization - is just that. So, if I gave you the subnets 10.0.0.0/24, 10.0.1.0/24, you could summarize that to 10.0.0.0/23. That means, if those two subnets are connected to seperate interfaces on your router, say on the "inside," then on your router - you could advertise on the "outside" that you know about 10.0.0.0/23 - this technique helps keep routing tables compact.

Cisco's site can give you the rest, but if you understand the basics as listed above, you're halfway there.

Good day!
Paul