A perimeter in technology is an organization’s boundary between its own network and the outside networks that neighbor it. For example, one of a company’s network perimeters might be the line between its private network and the Internet, through which online users access their website and portals. A border router, which sits between a business’s router and a user’s router, is part of the business’s last defense. It observes and filters some of the network traffic.
A firewall in a network perimeter performs a large amount of filtering and controlling Internet traffic into a private network. Firewalls look for suspicious activity and unusual requests, observe packets as they pass through the network, and may halt certain traffic if configured to do so. Users can configure their organization’s firewall to limit certain traffic to web pages or block particular requests.
Network perimeters perform intrusion detection and prevention as well. Detection observes patterns in network traffic and sends alerts to administrators if anything appears suspicious or if the software witnesses an attack. Intrusion prevention is usually software installed into the system. Based on the network regulations configured within the software, intrusion prevention can prevent network requests, block traffic, and halt attacks.
The decline of network perimeters
The solid line of a network perimeter that surrounds an entire company’s network has faded with the widespread adoption of cloud computing and the Internet of Things. Networks now require different protocols and software to protect the data that passes across them. Workloads cross multi-cloud environments because businesses need greater flexibility for their cloud applications; employees access those applications from multiple devices around the world. Edge computing on local servers requires security to be localized as well, rather than being concentrated in one giant data center. Some security providers have begun implementing secure access service edge (SASE) technologies to secure the edge more thoroughly. The concept of a network perimeter is much less definable and visible than it once was.
The increase in remote work also requires businesses to monitor their network traffic more carefully. Authentication helps them to better manage who is accessing the network. Network control now goes far beyond just securing a perimeter.