Understanding Firewall by Ahmad Nauval Syahputra.pptx

A glimpse of educational slides which talks about Networking Defense System (Firewall)

1. Understanding Firewall A Gatekeeper for Your Network By Ahmad Nauval Syahputra

2. What is a Firewall? A firewall is a network security system that monitors and controls incoming and outgoing network traffic . It acts as a gatekeeper , filtering data packets based on predefined rules to protect your network from unauthorized access and malicious attacks.

3. Types of Firewalls Hardware Firewall : A physical device that sits between your network and the internet, providing dedicated firewall capabilities. Software Firewall : A software application that runs on your computer or server, offering firewall protection.

4. Key Functions of a Firewall Packet Filtering : Examines incoming and outgoing data packets, allowing or blocking them based on specific criteria like IP addresses, ports, and protocols. Stateful Inspection : Tracks the state of network connections to determine whether packets are part of legitimate conversations. Intrusion Detection and Prevention (IDP) : Identifies and blocks malicious activities like unauthorized access attempts, viruses, and worms. Application Control : Restricts access to specific applications or websites.

5. Understanding ufw : A User-Friendly Firewall ufw (Uncomplicated Firewall) is a command-line interface for managing Netfilter , the Linux firewall system. It provides a simplified way to configure and manage firewall rules.

6. Basic ufw Commands Enable ufw $ sudo ufw <enable>/<disable> # sudo ufw enable Check status of ufw $ sudo ufw status # this will show that ufw is run or not Create allow or deny rules for traffic flow $ sudo ufw <allow>/<deny> [port/protocol] # sudo ufw allow 22/tcp

7. Deleting ufw rules Delete rules created in ufw $ sudo ufw delete <allow>/<deny> [port/protocol] Example : $ sudo ufw delete allow 22/tcp

8. Additional ufw feature Profiles : Predefined sets of rules for common scenarios (e.g., "default", "deny", "allow"). Logging : Records firewall activity for analysis and troubleshooting. Chain Manipulation : Allows you to modify the order in which rules are evaluated.

9. A Glimpse into iptables : The Core of Linux Firewalls iptables is the underlying framework that powers Linux firewalls. It provides a more granular level of control over firewall rules compared to ufw.

10. Basic iptables Concepts Tables : Different tables for different types of traffic (e.g., " filter ", " nat ", " mangle "). Chains : Predefined chains within each table (e.g., " INPUT ", " OUTPUT ", " FORWARD "). Rules : Individual rules that define actions to be taken on packets .

11. Example iptables Rule Example : $ sudo iptables -A INPUT -p tcp --dport 22 -j ACCEPT This rule allows incoming TCP traffic on port 22 (SSH) and accepts it . Note: While iptables offers greater flexibility , it requires a deeper understanding of networking concepts and can be more complex to manage.

12. Thank You