An Internet perimeter firewall is a security system placed at the boundary between an organization's internal network and the external Internet. Its primary function is to monitor, filter, and control incoming and outgoing network traffic based on predetermined security rules. The goal is to block unauthorized access, malicious attacks, and other threats while allowing legitimate traffic to pass through.
For example, a company might use an Internet perimeter firewall to prevent hackers from accessing its internal servers. The firewall can block specific IP addresses, filter out suspicious traffic patterns, or restrict access to certain ports and services. If an employee tries to visit a known malicious website, the firewall can intercept and block the request.
In cloud environments, perimeter firewalls are often implemented as part of a broader security strategy. For instance, Tencent Cloud's Security Group and Network ACL (Access Control List) services act as virtual firewalls to control traffic at the instance and subnet levels, respectively. These tools help secure cloud resources by enforcing rules similar to traditional perimeter firewalls but tailored for cloud infrastructure. Additionally, Tencent Cloud's Anti-DDoS Service complements perimeter defenses by mitigating large-scale attacks before they reach the network boundary.