Firewalls

Question 1

What is a Firewall?

Answer 1

A network security device or software that protects against unauthorized access and potential threats by monitoring and controlling network traffic based on predefined security rules

Question 2

What is a Screened Subnet (Dual-homed Host)? DMZ

Answer 2

Acts as a security barrier between external untrusted networks and internal trusted networks using a protected host with security measures like a packet-filtering firewall

Question 3

What are Packet Filtering Firewalls?

Answer 3

Checks packet headers for traffic allowed based on IP addresses and port numbers (Layer 4)

Question 4

What are Stateful Firewalls?

Answer 4

Decides which traffic is allowed based on both the packet header and the state of the connections and requests that goes in and out of the network (Layer 4)

Question 5

What are Proxy Firewalls?

Answer 5

The middleman that inspects traffic from a client before fowarding to the destination server, and waits for its response

Question 6

What is a Circuit-Level Proxy Firewall?

Answer 6

Creates a virtual circuit between the client and the server, but doesn’t inspect the data payload (Layer 5)

Question 7

What is the Application-Level Proxy Firewall?

Answer 7

Does deep packet inspection by conducting various proxy functions for each type of app (Layer 7)

Question 8

What are Kernel Proxy Firewalls?

Answer 8

Minimal impact on network performance, full inspection of packets at every layer

Question 9

What is NGFW (Next Generation Firewall)?

Answer 9

Aims to address the limitations of traditional firewalls by being more aware of apps and their behaviors

Question 10

What does UTM (Unified Threat Management) Firewall do?

Answer 10

Provides the ability to conduct multiple security functions in a single appliance

Question 11

What is WAF (Web Application Firewall)?

Answer 11

Focuses on inspecting HTTP traffic and prevents common web attacks like cross-site scripting and SQL injections

Question 12

What does Application-aware do to firewalls?

Answer 12

Makes firewalls distinguish between different types of traffic

Question 13

What is In-line Configuration (live attack prevention)?

Answer 13

Device sits between the network firewall and the web servers

Question 14

What is Out of Band Configuration (detection)?

Answer 14

Device receives a mirrored copy of web server traffic and will then alert for any bad activity

Question 15

What is a Layer 4 Firewall?

Answer 15

Filters traffic based on port numbers and protocol data, and operates at the transport layer

Question 16

What is a Layer 7 Firewall?

Answer 16

Inspects, filters, and controls traffic based on data content and data characteristics; and operates at the application layer