Networking Ch 6 - Firewalls

A software- or hardware-based network security system that allows or denies network traffic according to a set of rules.

• Firewall

• Router

• Switch

• Bastion

A list of filtering rules that firewalls use to identify allowed and blocked traffic.

• Access Control List

• Firewall

• Chain Event Log

• Filter Access List

Network-based firewalls are more expensive and require more configuration than other types of firewalls, but they are much more robust and secure.

• True

• False

Most network-based firewalls are not considered hardware firewalls even though they use a combination of hardware and software to protect the network from internet attacks.

• True

• False

Answer explanation

Read each question twice to catch "not" statements!

Almost all host-based firewalls are software firewalls.

• True

• False

You can use a host-based firewall in addition to a network-based firewall to provide multiple layers of protection.

• True

• False

Firewalls use filtering rules to identify allowed and blocked traffic. The filtering rules are also referred to as _________

• Access Control Lists

• File Access Lists

• Chained Log Filters

• Filter Control Lists

On what OSI layer does a packet filtering firewall operate?

• Layer 2

• Layer 3

• Layer 4

• Layer 7

Answer explanation

A packet-filtering firewall allows and blocks network traffic by examining information in the IP packet header such as source and destination addresses, ports, and service protocols. A packet filtering firewall:

Operates at OSI Layer 3 (Network layer).

A packet-filtering offers lower performance than other types of firewalls.

• True

• False

Answer explanation

A packet-filtering firewall allows and blocks network traffic by examining information in the IP packet header such as source and destination addresses, ports, and service protocols. A packet filtering firewall:

Offers high performance because it examines only the address information in the packet header.

On what OSI level does a circuit-level gateway operate?

• Layer 3

• Layer 4

• Layer 5

• Layer 7

Answer explanation

A circuit-level gateway makes decisions about the traffic to allow based on virtual circuits or sessions. A circuit-level gateway:

Operates at OSI Layer 5 (Session layer).