P300H P300 Series Modem Installation and Operating Handbook Page 28
[Drop /Insert Feature]Bearer Types T1-D4, T1-ESF, and G.732.
Timeslot Selection Independent selection of arbitrary timeslots for both Drop and Insert.
Bearer Generation The terrestrial bearer may be looped through the Drop mux then Insert
mux, or terminated after the Drop mux and a new blank bearer
generated by the Insert mux. The bearer generated within t he Insert mux
provides full multiframe and CRC support and may be generated from
the Tx Clock, Station Reference, Satellite Clock or Internal reference.
Bearer Backup In th e event that the Insert mux bearer clock is lost, or AIS is supplied,
then the Insert mux will switch temp orarily to bearer generation mode in
order to preserve the receive traffic. The backup bearer may be
generated from the Station Reference, Satellite Clock or Internal
reference.
Terrestrial CRC Fully supported, wi t h front panel display of terrestrial error rate based on
CRC (T1-ESF and G.732) or Frame Alignment Word errors (all bearer
types)
Timeslot ID Maintenance The IB S/SMS or Closed Net p l us ESC overhead maintains the identity of
individual D/I timeslot s for N=1, 2, 3 , 4, 5, 6, 8, 10, 12 , 15, 16, 20, 24 , 30
(see Extended D/I Feature below).
[Extended Drop/ Insert Feature]Timeslot Re-ordering Selected timeslots may be independently re-ordered on both Tx and Rx
paths.
Timeslot ID Maintenance The IB S/SMS or Closed Net plus ESC overhead is extended to maintain
the identity of individual D/I timeslots for all values of N from 1 to 31,
including the previously unavailable values N=7, 9, 11, 13, 14, 17 - 19, 21
- 23, 25-29, and 31.
Multi-destinational working All or only a subset of the received data may be inserted into the
terrestrial bearer on the receive path for multi-destinational working.
Signalling Both Channel Associated Signalling (CAS), and Robbed Bit Signalling
(RBS) are fully supported:
For E1 G.732 Drop/Insert, CAS signalling is extracted from terrestr ial
TS16 and carried over the satellite in IBS/SMS TS16 and TS48
before re-inserting into the dis tant terrestrial TS16
For T1-D4 and T1-ESF RBS the IBS or Closed Net plus ESC
overheads maintain the identity of the in band signalling, and it is
re-inserted into the terrestrial multiframe in the correct positions to
maintain the RBS.
[Async ESC Feature] & Aux Data Channel