ACL's and the established command

dagr8tim

If I seem like I'm posting too much, I'm sorry. I just seriously got back into studying for my CCNA after a 2 month sabatical. So I'm running across some concepts that I never really understood and I want to make sure I totally understand them.

Ok, I was brushing up on access lists tonight and I ran across the "established" command. This is the first time I've heard of it, and I think I understand how it's used. It you could set an outbound ACL to only allow port 80 transmission to enter the cloud. Then set the established command on the inbound ACL so that only packets that were requested from inside the network would pass.

My question is: Is this a new concept for like IOS 12.0 or did I sleep through part of the ACL lecture in the academy? If this is a new concept, will it work on older IOS's like 11.3?

Webmaster

If I seem like I'm posting too much, I'm sorry.

That's what the forum is for

dagr8tim wrote:

My question is: Is this a new concept for like IOS 12.0 or did I sleep through part of the ACL lecture in the academy? If this is a new concept, will it work on older IOS's like 11.3?

I will even work on IOS as early as 10.0(1).