L-3 Communications CEU, User Manual

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8510 Capabilities STE User’s Manual
9-12 Rel. 2.6
secure voice call between two ISDN STEs. The second method is to initiate a non-secure voice call and
press the SECVOICE Soft Key to initiate a secure voice call.
Using auto-secure call initiation ensures that your connection will have best secure voice quality possible
between those two STEs. If data bearers are available between two STEs, your STE signaling is
guaranteed. If data bearers are not available, the STE will attempt to perform STE signaling over voice
bearers. If the attempt is good, a secure call will still result in the best voice quality (SV32). If the attempt
fails, the call will revert to SCIP signaling and, if the receiving terminal is SCIP capable, the call will result
in a slightly lower voice quality secure connection (SV6.4 or SV2.4). If the receiving terminal is not SCIP
capable, the STE will revert to STU signaling. This will result in a still lower voice quality secure
connection (SV4.8 or SV2.4).
If a data bearer connection is established, the STE-8510 feature set contains data-bearer call
appearances, which causes call progress to happen a little differently than in STE versions earlier than
release 2.3. In versions before release 2.3, the call would be established on call appearances 1 through
6 on the STE. For release 2.3 and later, if your secure voice call is initiated by pressing the auto-secure
button, the call appearance automatically transfers to one of the data bearer call appearances as soon as
you dial the first digit. The data bearer call is annunciated by a character in the lower left corner of the
STE display rather than with an LED (
Figure 9-2 ). If a data bearer is not available through the network to
the other STE, the call is automatically transferred back to a voice bearer, after all digits have been
entered. A call appearance button with an LED will then control the call and the LED will be illuminated.
Figure 9-2. Data Bearer Call Annunciation
Transitioning to secure voice from a non-secure call will cause signaling to be performed over a voice
bearer. This type of call can result in a STE secure voice call if your voice bearer can support STE
signaling. If the voice bearer is STE capable, the effect will be a STE secure call (SV32). If the voice
bearer is not STE capable, the call reverts to SCIP and/or STU signaling to negotiate a secure call.
If you know you are placing a STE secure voice call from an STE-8510 on the 5ESS, select the
AUTOSEC Soft Key to ensure the highest secure voice quality.
9-5.1.2 Receiving Secure Voice Calls on 5ESS with STE-8510
The only difference between receiving your secure voice calls on 5ESS STE-8510 and any other STE is
that selecting the call will depend on the ring/idle preference setting on the line. If ring preference is
programmed at the switch, lifting the handset or pressing the speakerphone button will answer the
incoming call. If idle preference is set at the switch, lifting the handset or pressing the speakerphone
button will put you off-hook on an idle call appearance ready to dial a new call.
When a STE data bearer secure voice call is answered, the call automatically transfers to a data-bearer
call appearance and acts as if ring preference has been set. Otherwise, the call appearance handling will
happen as described above and the call will reside on a regular call appearance. Calls on normal call
appearances will negotiate to a signaling type compatible with the call initiator.
9-5.2 Secure Data Calls on 5ESS
Secure data calls are only available under front panel control in the STE-8510 mode. There is no remote
control capability when your STE is set to the STE-8510 switch type.
9-5.2.1 Placing Secure Data Calls on 5ESS with STE-8510
Similar to secure voice calls, you can establish your secure data calls in two different ways. The first
method is for you to establish an auto-secure secure data call between two ISDN STEs. The second
AUTO-SECURE MODE LINE SV 32
NONSEC
DIAL: 1
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