ACL Network Security & Traffic Filtering 3

Question 1

A named ACL uses 'ip access-list extended BLOCK_HTTP'. What advantage does the name provide?

Accepted Answer

It allows insertion or deletion of specific ACEs without rewriting the entire ACL

Answer

Named ACLs allow administrators to add, remove, or reorder individual ACEs using sequence numbers without deleting and recreating the entire ACL.

Question 2

Which protocol number is used in an ACL to match ICMP traffic?

Accepted Answer

1

Answer

ICMP is assigned IP protocol number 1, which can be used in extended ACLs with 'permit icmp' or 'permit 1'.

Question 3

An administrator configures 'access-list 50 permit 192.168.0.0 0.0.255.255'. Which traffic is permitted?

Accepted Answer

All hosts in the 192.168.0.0/16 network

Answer

The wildcard mask 0.0.255.255 allows the last two octets to vary freely, matching all 65,536 hosts in the 192.168.0.0/16 address space.

Question 4

What is a 'reflexive ACL' used for in network security?

Accepted Answer

Automatically permitting return traffic for sessions initiated from inside the network

Answer

Reflexive ACLs dynamically create temporary entries that permit return traffic for sessions initiated from the trusted inside network, providing stateful-like behavior.

Question 5

Which command verifies which ACLs are applied to a specific router interface?

Accepted Answer

show ip interface

Answer

'show ip interface' displays the inbound and outbound ACLs applied to each interface along with other IP interface statistics.

(ACL) Access Control Lists Practice Test

(ACL) Access Control Lists Practice Test

ACL Network Security & Traffic Filtering 3