Difference between ACLs and Firewall
 

Dear Experts,

Please tell me what is the difference between Firewall and ACL. why firewall is required between router and my LAN. can't i implement the rules of firewall through ACL in router?

Regards
Saif ur Rab

An ACL is a basic level of stateless packet filtering, as explained here. If that meets your (low) security requirements, then that's fine.

A firewall generally includes stateful packet inspection, a topic discussed in this PDF. This will provide a higher level of security than an ACL.

That said, you need to look at the specific implementations, as what one vendor calls an ACL another may call a firewall.

The term "ACL" can also mean "access control list," in the sense of being a mechanism that allows more finely-grained control over user access to resources .. such as files.

We all know (presumably) about the "user-group-world" "read-write-execute" permission flags of chmod, but so-called "hardened" distributions provide a great deal more security-controls than that ... ACLs.