The bitmap optimization method between ADSL modem and ADSL modem

摘要

PROBLEM TO BE SOLVED: To obtain an ADSL modem capable of optimizing bit map information in accordance with communication purposes while a line is connected, and to obtain a bit map optimizing method between ADSL modems.;SOLUTION: Upon receiving a VoIP communication request from a terminal (step S201) in a state where a line is connected to an ATU-C on a telephone central office side, an ATU-R as an ADSL modem to be installed on a subscriber side requests the ATU-C to switch bit map information (step S202). If switching verification is returned after switching preparation (step S204), the ATU-R performs switching notification for the ATU-C after transition state (step S206), and switches to communication with which training has been previously finished and which uses desired bit map information.;COPYRIGHT: (C)2006,JPO&NCIPI