COMSPHERE 392xPlus Modems
4-24
November 1996
3920-A2-GN31-30
Leased Line — Multiport Mode
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The Leased Line configuration options only appear when the Sync Leased factory preset template
is selected. They are used to configure the modem for operation over leased lines.
Table 4-4 shows each Leased Line configuration option as it appears on the LCD, with the Sync
Leased factory default setting (the default value if the modem is just being installed) shown
following the colon ( : ) on the first line and with all available selections listed on the second line.
Following this is a description of the configuration option. Factory default settings are listed in
Appendix F.
Table 4-4
(1 of 3)
Leased Line Configuration Options — Multiport Mode
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LeaseModulation: V34
Nxt V34 V32_Family TMp
Lease Modulation. Modulation reduces the amount of scrolling necessary to select Leased Line rates by limiting the
number of Leased Line Rate configuration options. Only one group of Leased Line rates is displayed depending on the
setting of the Lease Modulation configuration option (V.34, V.32bis, V.32 terbo, and TMp).
LeasedLine Rate: 28800(V34)
Nxt 33600 28800(V34) 24000(V34) 19200(V34) 16800(V34) 14400(V34) 12000(V34) 9600(V34) 7200(V34)
4800(V34) 2400(V34) 19200(V32t) 16800(V32t) 14400(V32b) 12000(V32b) 9600(V32b) 7200(V32b)
4800(V32b) 19200(TMp) 14400(TMp) 9600(TMp) 7200(TMp) 4800(TMp) 2400(TMp)
Leased-Line Rate. Determines the modem’s data rate and modulation scheme for operation on leased lines. These
modulation schemes are available on 2-wire or 4-wire lease.
33600, 28800(V.34), 24000(V34), 19200(V34), 16800(V34), 14400(V34), 12000(V34), 9600(V34), 7200(V34),
4800(V34), 2400(V34) – The modem operates using V.34 modulation at the data rate selected.
19200(V32t), 16800(V32t), 14400(V32b), 12000(V32b), 9600(V32b), 7200(V32b), 4800(V32b) – The modem operates
using V.32bis or V.32 terbo modulation at the data rate selected.
19200(TMp), 14400(TMp), 9600(TMp), 7200(TMp), 4800(TMp), 2400(TMp) – The modem operates in Trellis Multipoint
mode at the data rate selected. These modulation schemes are available on 4-wire leased lines. The 19200(TMp)
modulation does not appear on tributary modems.
Leased Mode: 4WLL-Ans
Nxt 4WLL-Ans 4WLL-Orig 2WLL-Orig 2WLL-Ans
Leased Mode. Sets the modem for either 2-wire or 4-wire operation in Answer mode (receiving a call) or 2-wire or 4-wire
operation in Originate (initiating a call) mode.
NOTE: For proper operation of V.34 or V.32 modulations over leased lines, one modem must be set to Originate mode
and the other set to Answer mode.
For Sync Leased Originate Mode, Async Leased Originate Mode and Trellis Multipoint Control Mode, 4-wire Originate is
the factory default.
Autorate: Enable
Nxt Enable Disable
Autorate. Once connected, the modem automatically lowers the line rate if line conditions become impaired. When line
conditions improve, the modem automatically shifts up to the highest data rate the line can support. This autorating only
occurs between 19,200 bps and 4800 bps during V.32, V.32bis, V.32 terbo connections, and 33.6 to 2400 for V.34.
