Unit3

1. What is a firewall in computing?

in computing, a firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

4. What are the functions of stateful filters?

Maintain knowledge of specific conversations between endpoints by remembering which port number the two IP address are using at the layer 4 (trasport layer) of OSI model for their conversation, allowing examination of the overall exchange between the nodes.

5. How can firewalls be categorized?

Firewalls can be categorized by processing mode, development era, or structure.

7. What is the most important benefit of application layer filtering?

The key benefit of application layer filtering it that can understand certain applications and protocols (such as File Transfer Protocol (FTP), Domain Name System (DNS), or Hypertext Transfer Protocol (HTTP)).

1. What does a commercial-grade firewall system consist of?

a commercial-grade firewall system consists of application software that is configured for the firewall application and run on a general-purpose computer.

3. What are most small office or residential-grade firewalls?

most small office or residential-grade firewalls are either simplified dedicated appliances running on computing devices or application software installed directly on the user’s computer.

4. What is one of the most effective methods of improving computing security in the SOHO setting?

One of the most effective methods of improving computing security in the SOHO setting is by means of a SOHO or residential-grade firewall

5. What method is used for protecting the residential user?

method of protecting the residential user is to install a software firewall directly on the user’s system.

7. Why do more and more small businesses and residences become more and more vulnerable to attacks?

As more and more small businesses and residences obtain fast Internet connections with digital subscriber lines (DSL) or cable modem connections, they become more and more vulnerable to attacks.

3. Which approach allows the router to prescreen packets to minimize the network traffic and load on the internal proxy?

Screened host firewalls

4. What is the protocol for handling TCP traffic via a proxy server?

SOCKS

6. How many NICs does the bastion host contain? What are they?

two NICS. One is connected external network, and one is connected internal network.

4. What do simple firewall models examine?

simple firewall models examine two aspects of the packet header: the destination and source address.

6. What does the packet-filtering firewall examine?

the header information of data packets that come into a network; every incoming packet.

7. What is the primary disadvantage of stateful inspection

The primary disadvantage of this type of firewall is the additional processing required to manage and verify packets against the state table.