Digicom 3911 Modem User Manual


 
Sample Configurations
G-33910-A2-GN32-40 September 1998
Multipoint
Figure G-2 shows a sample configuration for multipoint applications.
TMp control modems can accept mixed inbound rates from tributary modems. For example, one
inbound link may be configured for 14.4 kbps while another link experiencing line impairments
may be configured for 9.6 kbps. The following control/tributary rate combinations are allowed:
control at 19.2 kbps, tributaries at 14.4 or 9.6 kbps; control at 14.4 kbps, tributaries at 14.4 or 9.6
kbps; control at 9.6 kbps, tributaries at 9.6 or 7.2 kbps; control at 7.2 kbps, tributaries at 7.2 or 4.8
kbps; control at 4.8 kbps, tributaries at 4.8 or 2.4 kbps; control at 2.4 kbps, tributaries at 2.4 kbps.
Tributary rates will never exceed control rates. If tributary and control rates are equal, reducing the
control rate will automatically reduce the tributary rate.
Cable 1 Cable 1Cable 2Cable 2
Leased
19200(TMp) 14400(TMp)
TX TX
Cable 1Cable 2
14400(TMp)
TX
DTE
(Sync)
DTE
(Sync)
DTE
(Sync)
3910
A
3910
B
3910
C
Figure G-2. Sample Configuration Multipoint
Configuration Options
3910 A Use TMp (Control) default configuration options.
3910 B Use TMp (Trib) default configuration options.
3910 C Use TMp (Trib) default configuration options.
Cables
Cable 1 Use a standard, customer-supplied, EIA-232-D/V.24 cable with a DB-25-P (plug)
connector at one end to attach to the modem. Attach this to the connector labeled
DTE1.
Cable 2 Use part number 125-0053-1431 (an 8-position, 8-wire modular cord that is
supplied with the modem). Attach this to the connector labeled LEASED.