User Manual

Cross Connections | 137
T1 Framed Modes
Framed Mode Description
T1 - SF Provides 24 timeslots to transport traffic using the G.704 12 frame Super
Frame without signalling. There is no CRC capability with the SF.
T1 – SF 4 Provides 24 timeslots to transport traffic using the G.704 12 frame Super
Frame with 4 state signalling (AB bits). There is no CRC capability with the SF.
T1 – ESF Provides 24 timeslots to transport traffic using the G.704 24 frame Extended
Super Frame with CRC and without signalling.
T1 – ESF 4 Provides 24 timeslots to transport traffic using the G.704 24 frame Extended
Super Frame with CRC and 4 state signalling (AB bits).
T1 – ESF 16 Provides 24 timeslots to transport traffic using the G.704 24 frame Extended
Super Frame with CRC and 16 state signalling (ABCD bits).
For the 24 framed modes of ESF 4 and ESF 16, the Data Link bit is shown in the timeslot table but is
currently unavailable for use.
T1 - SF mode
T1 SF mode provides 24 timeslots to transport traffic using the G.704 12 frame Super Frame without
demultiplexing the signalling. Complete timeslots can be cross connected including the inherent
robbed signalling bits.
The timeslot table left column is used to map timeslot bits but the timeslot table right column for CAS
bits (ABCD) is not used.
T1 SF mode is used when access to the signalling bits is not required but are transported between
T1s, for example:
 Drop and Insert connections between 12 frame Super Frame T1s or data interfaces
T1 - SF 4 mode
T1 SF 4 mode provides 24 timeslots to transport traffic using the G.704 12 frame Super Frame with
four state demultiplexed signalling using the AB bits.
The mapping left column is used to map timeslot bits and the timeslot table right column is used to
map the CAS A&B bits for signalling (C&D bits are not used).
T1 SF mode is used when access to the signalling bits is required, for example:
 Cross connecting signalling from DFXS, DFXO or Q4EM interfaces into a 12 frame Super
Framed T1 using ‘multiplexed’ signalling from the interface.
 Drop and Insert connections between 12 frame Super Framed T1s or data interfaces
T1 - ESF mode
T1 ESF mode provides 24 timeslots to transport traffic using the G.704 12 frame Extended Super
Frame without demultiplexing the signalling. Complete timeslots can be cross connected including the
inherent robbed signalling bits.
The timeslot table left column is used to map timeslot bits but the timeslot table right column for CAS
bits (ABCD) is not used.
T1 ESF mode is used when access to the signalling bits is not required but are transported between
T1s, for example:
 Drop and Insert connections between 24 frame Extended Super Framed T1s or data interfaces