| 摘要 |
Signal distribution systems, such as interactive cable television systems, have a central server that communicates with remote terminals wherein the server assigns a specific address to each newly-connected terminal for control messages and polls. In the case of an interactive cable television system, such terminal is the set-top box or converter connected between the cable system and the television receiver. Periodically, the server broadcasts a control message containing a tentative address, and polls the tentative address. Upon receiving such a message, a newly-connected converter stores the tentative address and responds to the poll with an uplink message. After receiving the uplink message, the server inserts the tentative address in its polling list in accordance with the transmission delay measured from sending the poll to receiving the uplink message and selects a new tentative address to use in subsequent broadcast control messages. Uplink messages are echoed by the server and verified by the converter. If the converter cannot verify an echoed uplink message, which can occur if more than one newly-connected converter responds to the same broadcast control message, the converter repeats its initialization procedure to acquire a new address. After the initialization is complete, system software can be downloaded from the server to the converter and the converter placed in service.
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