A back-to-back connection links the output port of one device directly to the input port of another, bypassing intermediate routing or switching infrastructure. This topology is frequently used for testing throughput, troubleshooting interface faults, or establishing a dedicated, high-speed link between two redundant servers. It requires appropriate cabling, such as a crossover cable, if the interfaces do not support auto-negotiation.
Heard on the job
Let's wire the two routers in a back-to-back connection on the bench to verify the optical transceivers are working.