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Multi-frequency signaling

In telephony, multi-frequency signaling (MF) is a type of signaling that was introduced by the Bell System after World War II. It was in use since before 1949. It uses a combination of audible tones for address (telephone number) transport and supervision signaling on trunk lines between central offices. The signaling is sent in-band over the same…

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Multi-frequency signaling

Nodes26
Edges25
Triples1
Avg. degree1.92
Density0.076923
Components1

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signaling mf system telephone multi-frequency signals in-band bell address used uses number information audible frequencies systems signal kp type tones

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a blue box.Multifrequency signaling is a technological precursor of dual-tone multi-frequency signalinginstance ofthe systems proved vulnerable to misuse and fraud by phone phreaking with devices0.80text

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