ACL Types & Classification

Question 1

What is the primary function of an Access Control List (ACL)?

Accepted Answer

Control network traffic permissions

Answer

The primary function of an Access Control List (ACL) is to filter network traffic by defining rules that permit or deny packets based on various criteria. ACLs are configured on network devices like routers and firewalls to control which users or devices can access specific network resources. This mechanism is fundamental for enforcing network security policies and managing traffic flow.

Question 2

Which type of ACL filters traffic based on IP addresses and protocols?

Accepted Answer

Extended ACL

Answer

An Extended ACL provides granular control over network traffic by filtering packets based on a wider range of criteria compared to a Standard ACL. It can filter traffic using source and destination IP addresses, specific protocols (like TCP, UDP, ICMP), and even port numbers. This allows for highly specific and flexible security policies, enabling precise control over network access and services.

Question 3

What is a key characteristic of a Standard ACL?

Accepted Answer

Filters by source IP only

Answer

Standard ACLs are a basic type of access control list used in networking. Their key characteristic is that they can only filter traffic based on the source IP address of the packet. This makes them simpler to configure for basic access control, but less granular than other ACL types.

Question 4

Where is an Extended ACL typically applied in a network?

Accepted Answer

Near the source of traffic

Answer

Extended ACLs offer granular control, filtering traffic based on source IP, destination IP, protocols, and port numbers. Applying an Extended ACL near the source of traffic prevents unwanted traffic from consuming network resources unnecessarily as it traverses the network. This 'filter early' approach optimizes network performance and security.

Question 5

What distinguishes a Dynamic ACL from other types of ACLs?

Accepted Answer

Requires authentication before granting access

Answer

Dynamic ACLs, also known as Lock-and-Key ACLs, are unique because they are not static. They require a user to authenticate, typically via Telnet or SSH, before a temporary ACL entry is dynamically created to allow specific traffic. This provides on-demand access control, enhancing security by only opening ports when needed and for authenticated users.

(ACL) Access Control Lists Practice Test

(ACL) Access Control Lists Practice Test

ACL Types & Classification