| 摘要 |
PURPOSE: To support three or more line switching communication channels on one S interface bus by a single ISDN fundamental interface. CONSTITUTION: This system is implemented by establishing a multi-frame structure consisting of N subframes. Two consecutive subframes constitute a standard S/T interface frame conforming to the standard frame format defined in CCITT I. 400 series recommendations. Each subframe includes one octet of B1 bits, two octets of B2 bits, two D bits, and other information bits. A time slot of an octet of each B channel can be individually assigned to a low-band line switching communication channel defined as a subchannel. B1 and B2 channels and their bands corresponding to 64 kbps are divided into N sub-B1 channel and N sub-B2 channels and are assigned for communication of terminal equipments. |
