nätverksväxel

A nätverksväxel, commonly known in English as a network switch, is a networking device that connects multiple devices within a local area network (LAN) and forwards data packets between them. Unlike a hub, which broadcasts all traffic to every port, a switch uses packet switching to deliver data only to the destination device, thus improving bandwidth efficiency and reducing collisions.

The primary function of a switch is to learn and maintain a MAC address table, mapping each device’s unique MAC address to a specific port. When a frame arrives, the switch consults this table and forwards the frame only to the appropriate port, enabling simultaneous full‑duplex communication. Modern switches support advanced features such as VLAN segmentation, link aggregation, quality of service (QoS) prioritization, and secure management protocols.

Switches differ in design and capability. Unmanaged switches provide basic plug‑and‑play operation with no configuration options, suitable for home or small office use. Managed switches allow administrators to configure VLANs, set port security, and monitor network performance through console or web interfaces. PoE (Power over Ethernet) switches supply electrical power to connected devices such as VoIP phones or wireless access points, eliminating the need for separate power supplies. Layer‑3 switches combine routing functions with switching, enabling inter‑VLAN routing in larger enterprises.

Historically, switches emerged in the 1990s as a replacement for legacy hubs, driven by the need for higher throughput and better security in expanding LAN environments. Today, switches remain a foundational component of both enterprise networks and smaller deployments, forming the backbone of wired connectivity and enabling efficient, scalable network infrastructure.