Firewall Rules & Network Security

Imagine your cloud system is like a house

• You have doors
• Windows
• Valuables inside

Now if you leave everything open…
Anyone can enter

So what do you do?

• Install locks
• Allow only trusted people
• Block unknown visitors

In cloud, this protection is handled by Firewall Rules

What are Firewall Rules?

Firewall Rules control:
Incoming (Ingress) and Outgoing (Egress) network traffic

They decide:

• Who can connect
• Which ports are open
• What traffic is allowed or blocked

Key Components of Firewall Rules

1. Direction

• Ingress → Incoming traffic
• Egress → Outgoing traffic

2. Action

• Allow
• Deny

3. Protocol & Ports

• HTTP (80)
• HTTPS (443)
• SSH (22)

4. Source / Destination

• IP ranges
• Specific networks

Example Firewall Rule

Allows SSH access only from your system

Technical Example

Create firewall rule:

Secure SSH access

How Firewall Works

1. Request comes to server
2. Firewall checks rules
3. If allowed → Access granted
4. If denied → Blocked

Real-Life Examples

1. Website Hosting

• Allow HTTP/HTTPS
• Block other ports

2. Secure Admin Access

• Allow SSH only from trusted IP

3. Database Security

• Restrict access to internal network

4. Corporate Systems

• Control employee access