Which approach is commonly used in cybersecurity to achieve perimeter defense?

Firewalls are a fundamental component of cybersecurity and are specifically designed to establish a barrier between trusted and untrusted networks. They serve as a first line of defense, controlling incoming and outgoing network traffic based on predetermined security rules. This capability allows organizations to protect their internal systems from external threats, such as unauthorized access or attacks from the internet.

Firewalls can filter traffic based on various criteria, including IP addresses, protocols, and port numbers. They help prevent unauthorized users from accessing sensitive information, thereby contributing to a secure perimeter around the organizational network. In various configurations, such as packet filtering firewalls, stateful inspection firewalls, and next-generation firewalls, they can effectively monitor and control data flows, making them an essential tool in perimeter defense.

While antivirus software, encryption technologies, and intrusion detection systems play important roles in overall cybersecurity strategy and contribute to the protection of data and systems, they do not primarily focus on establishing a protective boundary around the network. Antivirus software provides endpoint protection, encryption secures data in transit or at rest, and intrusion detection systems monitor for suspicious activities but do not actively block them. Therefore, firewalls are the most suitable answer concerning perimeter defense.