Stateful and stateless firewalls differ in how they handle network traffic and maintain session information.
Stateful Firewalls:
- Differences: Stateful firewalls monitor and track the state of network connections. They maintain a table of active connections and can determine whether incoming traffic is part of an established session.
- Pros:
- More secure as they can recognize and allow only legitimate traffic that matches an existing session.
- Can handle complex protocols that require multiple connections.
- Provide better performance for trusted networks.
- Cons:
- Generally more resource-intensive due to the need to maintain session information.
- Configuration can be more complex.
Example: A stateful firewall might allow incoming traffic on port 80 (HTTP) only if it is part of an established outbound request to the same server.
Stateless Firewalls:
- Differences: Stateless firewalls examine each packet individually without tracking the state of connections. They make decisions based solely on predefined rules.
- Pros:
- Simpler to configure and manage.
- Less resource-intensive, making them faster for environments with high traffic loads.
- Cons:
- Less secure as they cannot distinguish between legitimate and malicious traffic based on session context.
- More prone to security vulnerabilities due to the lack of state tracking.
Example: A stateless firewall might block all incoming traffic on port 80 regardless of whether there is an established connection.
In the context of cloud services, Tencent Cloud offers firewall services that can be configured to operate in both stateful and stateless modes, providing flexibility based on specific security requirements and performance needs.