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Keywords from Image Description:
Festnetz Struktur.svg Telefonnetz Prinzipielle Struktur des Festnetzes own original caption eigene Zeichnung Skyhead Linien grne Linien Sprachkanle rote Linien SSSignalisierungsstrecken blaue Linien Datenstrecken Abkrzungen GW Internet Gateway STP Signalling Transfer Point SCP Service Control Point VE Vermittlungseinheit