Deck 9: Firewalls

Question 1

Generally,connections to instant-messaging ports are harmless and should be allowed.

Answer 1

False

Question 2

Which of the following is NOT among the common guidelines that should be reflected in the rule base to implement an organization's security policy?

A) only authenticated traffic can access the internal network
B) employees can use instant-messaging only with external network users
C) the public can access the company Web servers
D) employees can have restricted Internet access

Answer 2

B

Question 3

The Cisco PIX line of products is best described as which of the following?

A) software firewall
B) PC with firewall installed
C) firewall appliance
D) VPN gateway

Answer 3

C

Question 4

Which two ports should packet-filtering rules address when establishing rules for Web access?

A) 143, 80
B) 25, 110
C) 80, 443
D) 423, 88

Question 5

What type of attack are stateless packet filters particularly vulnerable to?

A) attempts to connect to ports above 1023
B) attempts to connect to the firewall
C) IP spoofing attacks
D) attempts to connect to ports below 1023

Question 6

Which of the following is a general practice for a rule base?

A) begin by blocking all traffic and end by allowing selective services
B) permit access to public servers in the DMZ
C) allow all access to the firewall
D) allow direct access from the Internet to computers behind the firewall

Question 7

What is considered the 'cleanup rule' on a Cisco router?

A) explicit allow all
B) implicit deny all
C) explicit prompt
D) implicit allow

Question 8

Which of the following is NOT a criteria typically used by stateless packet filters to determine whether or not to block packets.

A) IP address
B) ports
C) data patterns
D) TCP flags

Question 9

Which of the following is NOT a protocol,port pair that should be filtered when an attempt is made to make a connection from outside the company network?

A) TCP,80
B) TCP,139
C) UDP,138
D) TCP,3389

Question 10

Which of the following is a typical drawback of a free firewall program?

A) cannot monitor traffic in real time
B) oversimplified configuration
C) have centralized management
D) more expensive than hardware firewalls

Question 11

At what layer of the OSI model do proxy servers generally operate?

A) Application
B) Session
C) Transport
D) Network

Question 12

Stateless packet filtering keeps a record of connections that a host computer has made with other computers.

Question 13

Which element of a rule base conceals internal names and IP addresses from users outside the network?

A) tracking
B) filtering
C) NAT
D) QoS

Question 14

Since ICMP messages use authentication,man-in-the-middle attacks cannot be successful.

Question 15

Which of the following is described as the combination of an IP address and a port number?

A) portal
B) subnet
C) datagram
D) socket

Question 16

What is a suggested maximum size of a rule base?

A) 30 rules
B) 300 rules
C) 10 rules
D) 100 rules

Question 17

What should a company concerned about protecting its data warehouses and employee privacy might consider installing on the network perimeter to prevent direct connections between the internal network and the Internet?

A) router
B) VPN server
C) ICMP monitor
D) proxy server

Question 18

Firewalls can protect against employees copying confidential data from within the network.

Question 19

Software firewalls are usually more scalable than hardware firewalls.

Question 20

Which of the following is an advantage of hardware firewalls?

A) not scalable compared to software firewalls
B) not dependent on a conventional OS
C) less expensive than software firewalls
D) easy to patch

Question 21

A firewall can consist of all devices positioned on the network _____________.

Question 22

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
the end point of a computer-to-computer connection defined by an IP address and port address

Question 23

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
the collection of rules that filter traffic at an interface of a firewall

Question 24

What type of ICMP packet can an attacker use to send traffic to a computer they control outside the protected network?

A) Source Quench
B) Echo Request
C) Destination Unreachable
D) Redirect

Question 25

Which of the following is NOT an ICMPv6 packet type that you should allow within your organization but never outside the organization?

A) Destination unreachable
B) Packet too big
C) Time Exceeded
D) Packet Redirect

Question 26

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
software that forwards network packets and caches Web pages to speed up network performance

Question 27

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
a packet-filtering rule that comes last in a rule base and covers any packets that have not been covered by preceding rules

Question 28

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
a file maintained by stateful packet filters that contains a record of all current connections

Question 29

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
hardware or software configured to block unauthorized access to a network

Question 30

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
simple filters that determine whether to allow or block packets based on information in protocol headers

Question 31

The ACK flag is normally sent at the end of the three-way ______________ to indicate that a connection is established.

Question 32

What service uses UDP port 53?

A) SMTP
B) DNS
C) ICMP
D) TFTP

Question 33

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
filters that are similar to stateless packet filters,except that they also determine whether to allow or block packets based on information about current connections

Question 34

What are the two standard ports used by FTP along with their function?

A) UDP 23 control, TCP 20 data
B) UDP 20 data, TCP 21 control
C) TCP 21 control, TCP 20 data
D) TCP 23 data, TCP 21 control

Question 35

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
an addition to a security policy that describes how firewalls should handle application traffic,such as Web or e-mail applications

Question 36

MATCHING
a.cleanup rule
b.firewall
c.firewall appliance
d.firewall policy
e.proxy server
f.rule base
g.socket
h.state table
i.stateful packet filters
j.stateless packet filters
hardware devices with firewall functionality

Question 37

Which of the following is a method for supporting IPv6 on IPv4 networks until IPv6 is universally adopted?

A) Teredo tunneling
B) ICMPv6 encapsulation
C) IPsec tunneling
D) SMTP/S tunneling

Question 38

ACLs filter packets by using a __________ base to determine whether to allow a packet to pass.

Question 39

The rule base should permit access to public servers in the _________ and enable users to access the Internet.

Question 40

A primary objective of a rule base is to ______________ communications based on complex rules.

Question 41

What makes an effective rule base? List three points to consider.

Question 42

What is a cleanup rule? Provide an example.

Question 43

What are the most common features of IP protocol headers that stateless packet filters base their filtering decisions on?

Question 44

Describe a packet-filtering scenario that works with the DMZ.

Question 45

What happens when a packet hits a firewall? Discuss the possible actions that are taken.

Question 46

Describe a firewall policy for application traffic.

Question 47

Discuss what a firewall is and its role in a company's overall security scheme.

Question 48

Describe a hardware firewall and include one or more advantages and disadvantages.

Question 49

What is stateful packet filtering?

Question 50

Describe a software firewall and include one or more advantages and disadvantages.