Cisco CCNA Access Control Lists (ACLs) 5

Question 1

A VLAN ACL (VACL) differs from a routed ACL because it can filter traffic that is:

Accepted Answer

Both routed and bridged within the same VLAN

Answer

VACLs apply to all traffic within a VLAN, including Layer 2 bridged traffic that never passes through a routed interface.

Question 2

Which keyword in a standard ACL matches all hosts (equivalent to 0.0.0.0 255.255.255.255)?

Accepted Answer

any

Answer

The keyword 'any' is shorthand for source address 0.0.0.0 with wildcard 255.255.255.255, matching every IP address.

Question 3

What is the result of applying an ACL with only a 'deny' statement and no permit entries?

Accepted Answer

All traffic is denied due to the implicit deny any at the end

Answer

The single deny entry plus the implicit deny any at the end means all traffic is blocked.

Question 4

Which protocol number would you use in an extended ACL to match ICMP traffic?

Accepted Answer

1

Answer

ICMP is protocol number 1; TCP is 6, UDP is 17, and OSPF is 89.

Question 5

An administrator wants to log packets that match an ACL deny entry. Which keyword is added to the ACL entry?

Accepted Answer

log

Answer

Adding the 'log' keyword at the end of an ACL entry causes matching packets to generate a syslog message.

Cisco CCNA Practice Test