When configuring an ACL, where should extended ACLs ideally be placed?

When configuring an ACL, where should extended ACLs ideally be placed?

• A. Close to the destination IP address
• B. Close to the source of the traffic
• C. At network entry points
• D. On the router only

Answer: (B)

Extended ACLs should ideally be placed close to the source of the traffic. This placement is advantageous because it allows the network to filter packets before they traverse a significant portion of the network. By enabling the ACL at the source, unnecessary traffic is prevented from consuming bandwidth and processing resources further down the line. This proactive approach also helps in mitigating potential attacks at their origin, enhancing overall network security. Using the ACL at the source of traffic ensures that only legitimate packets are allowed to pass through to the destination, leading to more efficient network performance and reducing the load on routers and switches that might otherwise be processing unwanted traffic. This strategy aligns with the principle of least privilege, where only the minimal necessary access is granted, allowing for finer-grained control over network traffic. In contrast, placing the ACL close to the destination could still allow unwanted traffic to enter the network and consume resources before being blocked, which is less efficient. Additionally, while placing the ACL at network entry points can be useful, it does not always provide the optimal filtering capabilities that an extended ACL offers when positioned closest to the traffic source. The configuration on the router alone does not determine the optimal placement of access control lists; rather, the strategic positioning along the traffic path is what maximizes security and

Extended ACLs should ideally be placed close to the source of the traffic. This placement is advantageous because it allows the network to filter packets before they traverse a significant portion of the network. By enabling the ACL at the source, unnecessary traffic is prevented from consuming bandwidth and processing resources further down the line. This proactive approach also helps in mitigating potential attacks at their origin, enhancing overall network security.

Using the ACL at the source of traffic ensures that only legitimate packets are allowed to pass through to the destination, leading to more efficient network performance and reducing the load on routers and switches that might otherwise be processing unwanted traffic. This strategy aligns with the principle of least privilege, where only the minimal necessary access is granted, allowing for finer-grained control over network traffic.

In contrast, placing the ACL close to the destination could still allow unwanted traffic to enter the network and consume resources before being blocked, which is less efficient. Additionally, while placing the ACL at network entry points can be useful, it does not always provide the optimal filtering capabilities that an extended ACL offers when positioned closest to the traffic source. The configuration on the router alone does not determine the optimal placement of access control lists; rather, the strategic positioning along the traffic path is what maximizes security and