L-3 Communications CEU, User Manual

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Calls STE User’s Manual
7-24 Rel. 2.6
Example requiring two number dialing:
To place a call either from a TRI-TAC STE or a PSTN STE -
•
Call the IWF (Network Case #1), or call the TRI-TAC Switch (Network Case #2).
•
Upon hearing the second dial tone, dial the telephone number of the Called Party.
•
When the two subscribers wish to go secure, follow the normal procedures.
(The STEs will then cause different connectivity signaling to occur depending on whether or not
an IWF is present, but the signaling is automatic and no user interaction is required.
In order to allow for the increased signaling time required for the STEs to establish a common signaling
mode, the menu available “STU-III Extended Timeout” should be set to compatible network value. A
setting of 2 seconds is adequate for most network configurations, although a specific network
configuration may require a long Timeout setting. The “STU-III Extended Timeout” setting adds an
additional time allowance before the Initiator assumes that the Called Party is not going to respond, and
thereby prevents the Initiator from prematurely going to another step in the signaling sequence.
7-5. BDI VOICE CALLS
7-5.1 BDI - Initiating Calls
The EIA-530A/EIA-232 BDI interface provides two methods of communications: (1) a directed point-to-
point connection between STEs that requires no dialing or (2) via a modem, as in satellite
communications.
1. Upon going off hook, a point-to-point connection with the far-end is established. During the
connection establishment period, the STE presents the alerting display ( Figure 7-36 ). No user
options are available during this establishment part of the call.
Figure 7-36. BDI-to-BDI Connection Alerting Menu
The call is initiated in STU-III mode, non-secure voice (NSV) mode, at the rate of 4.8 kbps. The
mode may be changed to SECURE VOICE or SECURE DATA when the connection is
completed. The rate for the final mode may be 2.4, 4.8 or 9.6 kbps.
2. While the connection is being completed through the modems, the Clear-Idle display ( Figure
7-37 ) will be presented. The display may be briefly flashed on a landline connection but will be
display during the connection period while on a satellite link. While this display is presented, DO
NOT press either the
SECVOICE or SECDATA Soft Keys as it may cause an unrecoverable
fault that can only be cleared by re-initiating the call.
Figure 7-37. Modem Clear-Idle Display
After the call is successfully connected to the far-end terminal, the NON-SECURE menu will be
displayed and the call is handled accordingly.
ALERTING LINE1 NSV 4.8
CLEAR_IDLE_TO: LINE1 CI
SECDATA SECVOICE