As networks grew and enterprises began to experience slower network performance, Ethernet bridges (an early version of a switch) were added to networks to limit the size of the collision domains. In the 1990s, advancements in integrated circuit technologies allowed for LAN switches to replace Ethernet bridges. These LAN switches were able to move the Layer 2 forwarding decisions from software to application-specific-integrated circuits (ASICs). ASICs reduce the packet-handling time within the device, and allow the device to handle an increased number of ports without degrading performance. This method of forwarding data frames at Layer 2 was referred to as store-and-forward switching. This term distinguished it from cut-through switching.
As shown in Figure 1, the store-and-forward method makes a forwarding decision on a frame after it has received the entire frame and then checked the frame for errors.
By contrast, the cut-through method, as shown in Figure 2 begins the forwarding process after the destination MAC address of an incoming frame and the egress port has been determined.