Chapter 4
What is the wildcard mask that is associated with the network 192.168.12.0/24 ?
0.0.0.255
A network administrator is designing an ACL. The networks 192.168.1.0/25, 192.168.0.0/25, 192.168.0.128/25, 192.168.1.128/26, and 192.168.1.192/26 are affected by the ACL. Which wildcard mask, if any, is the most efficient to use when specifying all of these networks in a single ACL permit entry?
0.0.1.255
Which range represents all the IP addresses that are affected when network 10.120.160.0 with a wildcard mask of 0.0.7.255 is used in an ACE?
10.120.160.0 to 10.120.167.255
A network administrator configures an ACL with the command R1(config)# access-list 1 permit 172.16.0.0 0.0.15.255. Which two IP addresses will match this ACL statement? (Choose two.)
172.16.0.255 172.16.15.36
Which IPv4 address range covers all IP addresses that match the ACL filter specified by 172.16.2.0 with wildcard mask 0.0.1.255?
172.16.2.0 to 172.16.3.255
What range of IP addresses is represented by the network and wildcard mask 192.168.70.0 0.0.0.127?
192.168.70.0 to 192.168.70.127
Refer to the exhibit. This ACL is applied on traffic outbound from the router on the interface that directly connects to the 10.0.70.5 server. A request for information from a secure web page is sent from host 10.0.55.23 and is destined for the 10.0.70.5 server. Which line of the access list will cause the router to take action (forward the packet onward or drop the packet)?
3
What two functions describe uses of an access control list? (Choose two.)
ACLs can control which areas a host can access on a network. ACLs provide a basic level of security for network access.
Which three statements describe ACL processing of packets? (Choose three.)
An implicit deny any rejects any packet that does not match any ACL statement. A packet can either be rejected or forwarded as directed by the statement that is matched. Each statement is checked only until a match is detected or until the end of the ACL statement list is reached.
Which two packet filters could a network administrator use on an IPv4 extended ACL? (Choose two.)
ICMP message type destination UDP port number
Which statement describes a difference between the operation of inbound and outbound ACLs?
Inbound ACLs are processed before the packets are routed while outbound ACLs are processed after the routing is completed.
Which two statements are correct about extended ACLs? (Choose two)
Port numbers can be used to add greater definition to an ACL. Extended ACLs evaluate the source and destination addresses.
An administrator has configured an access list on R1 to allow SSH administrative access from host 172.16.1.100. Which command correctly applies the ACL?
R1(config-line)# access-class 1 in
Refer to the exhibit. A network administrator wants to permit only host 192.168.1.1 /24 to be able to access the server 192.168.2.1 /24. Which three commands will achieve this using best ACL placement practices? (Choose three.)
R2(config)# interface fastethernet 0/0 R2(config-if)# ip access-group 101 in R2(config)# access-list 101 permit ip host 192.168.1.1 host 192.168.2.1
A network administrator needs to configure a standard ACL so that only the workstation of the administrator with the IP address 192.168.15.23 can access the virtual terminal of the main router. Which two configuration commands can achieve the task? (Choose two.)
Router1(config)# access-list 10 permit host 192.168.15.23 Router1(config)# access-list 10 permit 192.168.15.23 0.0.0.0
Refer to the exhibit. A network administrator configures a named ACL on the router. Why is there no output displayed when the show command is issued?
The ACL name is case sensitive.
Refer to the exhibit. A network administrator is configuring an ACL to limit the connection to R1 vty lines to only the IT group workstations in the network 192.168.22.0/28. The administrator verifies the successful Telnet connections from a workstation with IP 192.168.22.5 to R1 before the ACL is applied. However, after the ACL is applied to the interface Fa0/0, Telnet connections are denied. What is the cause of the connection failure?
The IT group network is included in the deny statement.
Which two statements describe the effect of the access control list wildcard mask 0.0.0.15? (Choose two.)
The last four bits of a supplied IP address will be ignored. The first 28 bits of a supplied IP address will be matched.
Which statement describes a characteristic of standard IPv4 ACLs?
They filter traffic based on source IP addresses only
Which three values or sets of values are included when creating an extended access control list entry? (Choose three.)
access list number between 100 and 199 source address and wildcard mask destination address and wildcard mask
What two ACEs could be used to deny IP traffic from a single source host 10.1.1.1 to the 192.168.0.0/16 network? (Choose two.)
access-list 100 deny ip 10.1.1.1 0.0.0.0 192.168.0.0 0.0.255.255 access-list 100 deny ip host 10.1.1.1 192.168.0.0 0.0.255.255
Which set of access control entries would allow all users on the 192.168.10.0/24 network to access a web server that is located at 172.17.80.1, but would not allow them to use Telnet?
access-list 103 permit tcp 192.168.10.0 0.0.0.255 host 172.17.80.1 eq 80 access-list 103 deny tcp 192.168.10.0 0.0.0.255 any eq 23
Refer to the exhibit. The network administrator that has the IP address of 10.0.70.23/25 needs to have access to the corporate FTP server (10.0.54.5/28). The FTP server is also a web server that is accessible to all internal employees on networks within the 10.x.x.x address. No other traffic should be allowed to this server. Which extended ACL would be used to filter this traffic, and how would this ACL be applied? (Choose two.)
access-list 105 permit tcp host 10.0.70.23 host 10.0.54.5 eq 20 access-list 105 permit tcp host 10.0.70.23 host 10.0.54.5 eq 21 access-list 105 permit tcp 10.0.0.0 0.255.255.255 host 10.0.54.5 eq www access-list 105 deny ip any host 10.0.54.5 access-list 105 permit ip any any
Which two ACE commands will block traffic that is destined for a web server which is listening to default ports? (Choose two.)
access-list 110 deny tcp any any gt 75 access-list 110 deny tcp any any eq https
Which feature is unique to IPv6 ACLs when compared to those of IPv4 ACLs?
an implicit permit of neighbor discovery packets
Which three implicit access control entries are automatically added to the end of an IPv6 ACL? (Choose three.)
deny ipv6 any any permit icmp any any nd-ns permit icmp any any nd-na
Which two keywords can be used in an access control list to replace a wildcard mask or address and wildcard mask pair? (Choose two.)
host any
Which command is used to activate an IPv6 ACL named ENG_ACL on an interface so that the router filters traffic prior to accessing the routing table?
ipv6 traffic-filter ENG_ACL in
What is the only type of ACL available for IPv6?
named extended
Which IPv6 ACL command entry will permit traffic from any host to an SMTP server on network 2001:DB8:10:10::/64?
permit tcp any host 2001:DB8:10:10::100 eq 25
In applying an ACL to a router interface, which traffic is designated as outbound?
traffic that is leaving the router and going toward the destination host