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View Full Version : basic difference between classful & classless addressing!


swaminathan
12-18-2010, 01:37 PM
Hi

Please explain which criteria differentiate a classful addressing from classless ip addressing!


151.78.1.1/25 ip address is a classless ip address or classful ip address?


I found an interesting discussion in this link http://www.techexams.net/forums/ccna-ccent/15813-classeless-vs-vlsm-vs-cidr.html

In this discussion, I found the statement as follows:

This is incorrect, i can have a classful routing protocol with an address
151.78.1.1/25, in this case i must use /25 throughout my network when using a 151.78.x.x network address.


So I need which factor either the first few bits of an ip address or the subnet mask decides it's type classful or classless?

Thanks

Swaminathan

swaminathan
12-23-2010, 01:23 PM
Hi

I found the answer here : http://www.lammle.com/discussion/showthread.php?t=3461&highlight=swaminathan