CSS (KNC-301) 4. Packet Filtering Firewall By Vivek Tripathi.pptx

Packet Filtering Firewall

1. KALICHARAN NIGAM INSTITUE OF TECHNOLOGY BANDA SUB: Computer System Security Presented By Mr. VIVEK TTRIATHI ASSISTANT PROFESSOR DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING KCNIT,BANDA

2. TOPIC: Packet Filtering Firewall

3. What is a Firewall A Firewall is a network security device that monitors and filters incoming and outgoing network traffic based on an organization’s previously established security policies. A firewall is essentially the barrier that sits between a private internal network and the public Internet. A firewall’s main purpose is to allow non-threatening traffic in and to keep dangerous traffic out.

4.  Types of firewalls Firewalls are classified as either software or hardware firewalls, depending on their structure. Each type of firewall serves a distinct purpose while providing the same functionality. However, having both is recommended for maximum protection. A hardware firewall is a physical piece of equipment that connects a computer network to a gateway. Consider a broadband router as an example. An Appliance Firewall is another name for a hardware firewall. A software firewall is a simple program that is installed on a computer and operates via port numbers and other installed software. This type of firewall is also known as a Host Firewall.

5. There are four different types of firewalls. Packet Filtering Firewalls. Packet filtering firewalls are the oldest, most basic type of firewalls. Circuit-Level Gateways. Stateful Inspection Firewalls. Application-Level Gateways (Proxy Firewalls)

6. Firewall is a software or hardware The main difference between a hardware firewall and a software firewall is that the hardware firewall runs on its own physical device, while a software firewall is installed on another machine. A common example of a software firewall is the firewall built into most operating systems like Windows and macOS. These OS firewalls are bundled with the operating system and can run on any compatible hardware.

7. Packet Filtering Firewall A packet filtering firewall is a network security feature that controls the flow of incoming and outgoing network data. The firewall examines each packet, which comprises user data and control information, and tests them according to a set of pre-established rules. If the packet completes the test successfully, the firewall allows it to pass through to its destination. It rejects those that don't pass the test. Firewalls test packets by examining sets of rules, protocols, ports and destination addresses.

8. W hy do firewalls use packet filtering Packet filtering is an efficient defense system against intrusions from computers or networks outside a local area network (LAN). It is also a standard, and cost-effective means of protection as most routing devices possess integrated filtering capabilities, so there is no need to set a new firewall device.

9. Where is packet filtering firewall used: Packet-filtering firewalls operate  at the network layer (Layer 3) of the OSI model . Packet-filtering firewalls make processing decisions based on network addresses, ports, or protocols. Packet-filtering firewalls are very fast because there is not much logic going behind the decisions they make.

10. How is packet filtering used Packet filtering is a firewall technique used to control network access by monitoring outgoing and incoming packets and allowing them to pass or halt based on the source and destination Internet Protocol (IP) addresses, protocols and ports. Packets are structured data units. Because they divide communications into small bits and transport them independently across the network, these networks are fault-tolerant. In order to display accurate information, packages are reordered after passing through the firewall and arriving at their destination.

11. Packets include two essential components: Data is directed to the correct location using packet headers. They include internet protocol (IP) elements, addressing, and any other data needed to deliver packets to their destination. The user data contained within the packet is referred to as the payload. This is the data that is trying to get somewhere.

12. Example of Packet Filtering Firewalls : Denying outsiders access to port 80, for example, would prevent all outside access to the HTTP server, because most HTTP servers run on port 80. You can also configure your firewall to allow only packets intended for your mail or web server while rejecting all others.

13. Packet filtering firewalls allow or deny network packets based on the following criteria: The source IP address is where the packet is being sent from. The packet’s address is the destination IP address. Protocols: Protocols include data transfer protocols such as session and application protocols (TCP, UDP, ICMP). Ports include source and destination ports, as well as ICMP types and codes. Flags include TCP header flags such as whether the packet is a connect request. The physical interface (NIC) that the packet is passing through (incoming or outgoing).

14. Benefits of Packet Filtering Firewalls Packet filtering firewalls is best efficient method because Routers typically operate at high speeds, accepting and rejecting packets as quickly as possible based on their destinations, source ports, and addresses Packet filtering is extremely cost-effective because only one filtering router is required to secure the internal network. Packet filtering is an appealing option due to its low cost and ease of use

15. Drawbacks of using a Packet Filtering firewall The primary disadvantage of packet filtering is that it is based on IP address and port number rather than context or application information. Lack of Logging Capabilities:  If the packet filter lacks logging capabilities, it can pose a problem for a company that must meet compliance and reporting requirements. Packet filtering is that it is fundamentally stateless, which means that it monitors each packet independently, regardless of the established connection or previous packets that have passed through it. As a result, the ability of firewalls to protect against severe threats and attacks is quite limited.