According to the different operation modes of the Ethernet Quality Tester processing frames, it can be mainly divided into two categories.
Store and forward: The switch must receive the entire frame before forwarding, and perform error detection. If there is no error, send the frame to the destination address. The forwarding delay of a frame through a switch varies with the length of the frame.
Straight-through: The Ethernet Link Tester forwards the frame as soon as it checks the destination address contained in the frame header, without waiting for all frames to be received, and no error checking. Since the length of the Ethernet frame header is always fixed, the forwarding delay of the frame through the switch remains unchanged.
The straight-through forwarding speed is much faster than the store-and-forward mode, but the reliability is worse because it is possible to forward conflicting frames or frames with CRC errors.