T1-D4/T1-D4-S; T1-Esf/T1-Esf-S; Multidestinational Systems - Radyne DMD20 Installation And Operation Manual

DMD20/20LBST Universal Satellite Modem
H.1.3.5

T1-D4/T1-D4-S

The T1-D4 Mode of Operation supports a T1 Interface with 12 frames per multiframe. The user
may independently program n timeslots to drop and n timeslots to insert where n = 1, 2, 3, 4, 5, 6,
8, 10, 12, 15, 16, 20, 24, or 30. Robbed Bit Signaling (RBS) is handled without any need for
operator intervention and is transparent to the user.
H.1.3.6

T1-ESF/T1-ESF-S

The T1-ESF Mode of Operation supports a T1 Interface with 24 frames per multiframe. The
CRC-6 checksum is automatically checked by the Drop Function and generated by the Insert
Function and placed in the appropriate F-bit positions in the terrestrial multiframe. The user may
independently program n timeslots to drop, and n timeslots to insert, where n = 1, 2, 3, 4, 5, 6, 8,
10, 12, 15, 16, 20, 24, or 30. Robbed Bit Signaling (RBS) is handled without any need for
operator intervention and is transparent to the user.
H.1.4 Multidestinational Systems
Because the Drop and Insert Functions are completely independent, so multi-destinational
communications are easily supported.. Figure H-6 illustrates a Multi-destinational System with
one Hub site and three remote sites. At the Hub site, thirty channels are being transmitted to all
three remote sites and a fractional set of channels is being received from each remote site. At
the other end of the link, each remote site is transmitting a fractional E1 to the Hub site as well as
receiving all 30 channels from the Hub site. It also identifies those channels intended for it, and
inserts them into the terrestrial data stream.
MN-DMD20-20LBST Revision 14
Drop and Insert (D&I)
H–5