What are ACLs?

ACLs (Accsess Control Lists) have multiple uses.

Controls which devices have access to certain parts of the network.

ACLs funtion as a packet filter, instructing the router to permit or discard specific traffic.

ACLs can filter traffic based on source/destination IP addresses, source/destination Layer 4 ports, etc.

Requirements

• Hosts in 192.168.1.0/24 can access the 10.0.1.0/24 network.

• Hosts in 192.168.2.0/24 cannot access the 10.0.1.0/24 network.

ACLs are configured globally on the router. (global config mode)

They are an ordered sequence of ACEs. (Access Control Entries)

ACL1:

1. if source IP = 192.168.1.0/24, then permit

2. if source IP = 192.168.2.0/24, then deny

3. source IP = any, then permit

Configuring an ACL in global config mode will not make the ACL take effect.

The ACL must be applied to an interface.

ACLs are applied either inbound or outbound.

The ACL was not applied correctly, and the PC3 was able to reach the SRV1

It work, but it is too restrictive because PC3 and PC4 will only be able to communicate between them

This is the best approach