It is possible Kopfstellen is the opposite of Endkunden, in this
context, in considering the terminations of a connection. This is just a guess, but it sounds so close to the Spanish "cabecera de línea, puesto de cabecera" and the French "terminaison" in the telecom context. I wouldn't really use switchboard technology to explain this, but the "ends" of a phone line are considered to be found in regional, national and international telecoms centers.
Local time: 11:27
Native speaker of: English
PRO pts in pair: 315