Portbaseret

Portbaseret is a term used in Danish to describe systems and processes that are organized around network ports or interface points. In information technology it is most often encountered in the context of port-based network access control, a security approach that governs access to a network at the level of individual switch or wireless LAN ports.

In a typical port-based access control implementation, a device (the supplicant) connects to an access port on a network device (the authenticator). Until the device is authenticated by an authentication server (usually via RADIUS), the port remains in a restricted or unauthorized state, preventing access to network resources. After successful authentication, the port is granted access, optionally with dynamic VLAN assignment, ACLs, or quality-of-service policies.

Key components include the supplicant, the authenticator, and the authentication server. Common protocols involve EAP methods used by the supplicant, transmitted between the authenticator and the server. The model is central to IEEE 802.1X standards, which underpin many implementations in both wired and wireless networks.

Uses and benefits include improved security by ensuring only authenticated devices can access the network, support for network segmentation through per-port VLANs, and centralized policy enforcement. Limitations include the need for a functioning authentication infrastructure, potential risk of lockouts due to misconfiguration, and added management overhead and potential latency.

Related concepts encompass network access control (NAC), RADIUS, VLAN, EAP, and MAC-based access control as broader or alternative approaches. The concept has evolved with enhancements for wireless and IoT environments, reflecting ongoing efforts to balance security and usability at the port level.