Mobile Telephone Switching Office. Contains a “switch,” a large computer that manages the carrier’s cellular network by

controlling the cell sites and monitoring the signal strength. When a mobile phone begins to leave a cell, the switch

senses that the signal is becoming weak and hands the call over to the next closest antenna that has a stronger signal. If

the call is “mobile‐to‐land,” the switch puts the call through to the local landline company or phone company that

connects the call to the person whom the customer called. If the call is “mobile‐to‐mobile,” the switch puts the call

through to the cellular customer being called.