[Kymmy]

Patch means short cable as in about 50cm designed to connect network switches to patch panels. I presume you mean crossover or straight which as most ports are auto set it doesn't really matter but in the old days straight tend to connect devices to hubs and crossover from device to device. Cat 6 or 6e? If you're only going upto gigabytes then get either..

As to exact answers it's about 9 inches that wet piece of string... In other words details like distance, speed..etc are needed before you'll get an exact answeer