extended access-list

[cisc0.ameer]

hello

ip access-list ext SOMETHINGS

permit ip 10.0.0.0 0.0.0.255   255.255.255.0  0.0.0.255

permit ip 10.0.0.0 0.0.0.255   host 255.255.255.252

i know the result because i tested but i can not realize that bold line why 255.255.255.0 0.0.0.255( i know it based on Subnet mask)

i get confused first is IP & second is wild sub Mask

what is mean exactly ?

it means while we want to PER/DENY from subnet mask e.g /24 we have to write:

255.255.255.0 0.0.0.255

[luis_cordova]

Hola @cisc0.ameer ,

it means while we want to PER/DENY from subnet mask e.g /24 we have to write: 

255.255.255.0 0.0.0.255

A: Exactly, but, do not confuse 255.255.255.0 with a mask /24

The policy of the ACL remains the same IP/wildcard

In this case:

permit ip 10.0.0.0 0.0.0.255   255.255.255.0  0.0.0.255

This ACE indicates that the packages that start with the ip 10.0.0.X and go to any destination that starts with the ip 255.255.255.X will be allowed.

Regards