Question 1: You See A Network Topology And An Empty Firewall
Question 1you See A Network Topology And An Empty Firewall Rule Table
You see a network topology and an empty firewall rule table. Internal LAN is the network in which user computers have been located. DMZ is the demilitarized zone in which bastion hosts have been placed. You can see a web server in the DMZ. The role of the webserver is to serve the web pages hosted on it to the Internet over port 80/http service.
It is a strict company policy that all of the computer users within Internal LAN can access to port 80/http and port 443/ssl services on the Internet. All of the network traffic other than the mentioned above should be blocked and logged. Please create the required rule (ACL) table. . Rule # Source IP/Network/Any Target IP/Network/Any Target Service (Port Number or Service Name) Action (Allow or Block) Logging (Enabled or Disabled)
Paper For Above instruction
The design and implementation of a secure firewall rule table are vital components of network security, especially within organizations with sensitive information and strict access policies. In the given scenario, there is a need to configure firewall rules based on a specified network topology, consisting of an Internal LAN, a DMZ with a web server, and the broader internet. The core objective is to allow internal users to access specific services while blocking all other traffic, and to log any unauthorized or disallowed traffic attempts.
Understanding the Network Topology and Policy Requirements
The network topology comprises three main segments: the Internal LAN, the DMZ (demilitarized zone), and the Internet. The Internal LAN contains user workstations, which require access to port 80 (HTTP) and port 443 (HTTPS/SSL) for web browsing. The DMZ hosts the web server that serves web pages to external clients over port 80. The Internet represents external sources that initiate outbound connections or potentially malicious inbound attempts.
According to the organization's policy, all internal users must be permitted to access only ports 80 and 443 on the Internet, and all other outbound traffic should be blocked and logged for security and auditing purposes. Moreover, inbound traffic to the web server from the Internet should be permitted on port 80, reflecting standard web service operation.
Designing the Firewall Rules
To meet these requirements, a set of explicit firewall rules (ACLs) must be crafted. These rules typically operate in sequence, with each rule either permitting or denying specific traffic. The rules should prioritize allowing legitimate and necessary communications while denying everything else by default.
For outbound traffic originating from Internal LAN, rules should permit HTTP and HTTPS traffic to any destination IP, logged for auditing. Unauthorized outbound connections on other ports should be blocked and logged. For inbound traffic towards the web server, rules should permit HTTP requests from any source over port 80. Conversely, all other inbound traffic should be explicitly blocked and logged.
This approach ensures compliance with the company's security policies and helps in auditing potential threats or unauthorized access attempts.
Proposed Firewall Rule Table
| Rule # | Source IP/Network/Any | Target IP/Network/Any | Target Service (Port Number or Service Name) | Action (Allow or Block) | Logging (Enabled or Disabled) |
|---|---|---|---|---|---|
| 1 | Internal LAN | Any | Port 80 / HTTP | Allow | Enabled |
| 2 | Internal LAN | Any | Port 443 / HTTPS | Allow | Enabled |
| 3 | Any | Web Server IP | Port 80 / HTTP | Allow | Enabled |
| 4 | Internal LAN | Any | Any (other than ports 80 and 443) | Block | Enabled |
| 5 | Any | Any | Any | Block | Enabled |
Explanation of the Firewall Rules
Rule 1 and 2 permit internal users to access HTTP and HTTPS services on the Internet, complying with policy. Rule 3 allows external users to access the web server on port 80, facilitating web hosting services. Rule 4 blocks any other outbound traffic from the internal network that is not on ports 80 or 443, avoiding unauthorized access or data exfiltration, with logging enabled for audit trails. Rule 5 acts as a default deny rule, blocking all other traffic not explicitly permitted, ensuring strict control over network communications, and logging such attempts for analysis.
Conclusion
Implementing these rules structurally aligns with best practices in network security by establishing a clear permit-and-deny hierarchy, minimizing attack surfaces, and enabling comprehensive logging. Properly configured Firewalls protect organizational resources, prevent unauthorized data access, and provide critical logs for troubleshooting and forensic analysis, essential components of a robust security posture.
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