What is a Switch Fabric?

A switch fabric refers to the internal architecture of a network switch that connects its ports and facilitates data forwarding. It enables communication between the switch’s ports by determining how data packets are routed from one port to another. The switch fabric plays a crucial role in the switch’s overall performance and capacity, as it directly impacts throughput, latency, and the efficiency of the data transfer process. In high-performance network switches, the switch fabric typically features multiple connections and high-speed paths to ensure fast and efficient data movement between ports.

Formula to Calculate Switch Fabric:
Total Bandwidth = Port Number x Speed x Duplex Mode.

Example Scenario: Switch Fabric in a 5-port FE vs 8-port GbE Switch:

1. 5-Port Fast Ethernet (FE) Switch:
   • Each port can send and receive 100Mbps. This will equal to 200Mbps if sending and receiving concurrently. Therefore if there’s 5-ports and each are a lotted 200Mbps of bandwidth then the overall Switch Fabric is 1,000Mbps or 1Gbps.
2. 8-Port Gigabit Ethernet (GbE) Switch:
   • Each port can send and receive 1000Mbps. This will equal to 2000Mbps if sending and receiving concurrently. Therefore if there’s 8-ports and each port is a lotted 2000Mbps of bandwidth then the overall Switch Fabric is 16,000Mbps or 16Gbps.

Content created by Mike Day