L-3 Communications CEU, User Manual

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8510 Capabilities STE User’s Manual
9-14 Rel. 2.6
An easy rule of thumb is to only give the data number to another STE user whose STE has an ISDN
connection. When you do give them the number, remind them to place auto-secure calls to the data
module so that a data bearer is requested. You should also give ISDN STE users the voice station
number, in case they cannot establish an End-to-End ISDN connection. If an End-to-End ISDN
connection is not available to the DEFINITY data module number, the initiating terminal will receive a
reorder tone (an alternating high-low tone alarm, sounding like a European-style police siren).
9-6.1 Placing Secure Voice Calls on DEFINITY With STE-8510
When your STE is configured to the STE-8510 switch setting on a properly configured DEFINITY switch,
your secure voice calls can be established in two different ways. The first method is for you to establish
an auto-secure secure voice call between two ISDN STEs. The second method is to initiate a non-secure
voice call, and then press the SECVOICE Soft Key to initiate a secure voice call.
Using auto-secure call initiation ensures the connection will have best possible secure voice quality
possible between the two STEs. If data bearers are available between two STEs, STE signaling is
guaranteed. If data bearers are not available, the STE will attempt to perform STE signaling over voice
bearers. If the number being called is a DEFINITY data module number, this voice bearer attempt will fail
resulting in the initiating terminal receiving a reorder tone and a failed non-secure call. You should
reattempt the call using the voice station number. If the STE signaling attempt over voice bearers 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 resulting in a still lower voice quality secure connection (SV4.8 or SV2.4).
If the data bearer connection is established, the STE-8510 feature set contains data bearer call
appearances and call progress will happen a little differently than it would 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 a secure voice call is initiated by pressing the auto-secure
button, the call appearance will automatically be transferred to one of the data bearer call appearances as
soon as the first digit is dialed. The data bearer call will be 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 will automatically be transferred back to a voice bearer after all
digits have been entered. A call appearance button with an LED will then control the call.
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 (SV32) if the voice bearer is capable of
supporting STE signaling. If the voice bearer is not STE capable, the call will revert to SCIP and/or STU
signaling to negotiate a secure call.
If you know you are placing a STE secure voice call from a STE-8510 on the DEFINITY; select the
AUTOSEC Soft Key to ensure the highest secure voice quality.
9-6.2 Receiving Secure Voice Calls on DEFINITY With STE-8510
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
occur as described above, and your call will reside on a regular call appearance. Calls on normal call
appearances will negotiate to a signaling type compatible with the call initiator.
9-6.3 Secure Data Calls on DEFINITY
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.
9-6.3.1 Placing Secure Data Calls on DEFINITY with STE-8510
Similar to secure voice calls, secure data calls can be established in two different ways. The first method
is to establish an auto-secure secure data call between two ISDN STEs. The second method initiates a
non-secure voice call and a press of the SECDATA Soft Key initiates a secure data call.