Encrypted Trunk

Whenever a SNAP user wishes to place a secure call, his LISphone or LIScell will first establish a secured session with the LIStrunk and will transmit the destination number dialed by the subscriber to the LIStrunk. The LIStrunk establishes an outgoing call to the destination number and notifies the subscriber via a tone as to the level of security achieved on the connection (i.e. whether the security is end-to-end or “half way”).
Similarly, incoming calls are also secured whenever the calling party initiates a call using a special telephone number, which will flow trough the LIStrunk. These operations, which are seamless to the end-user, continuously secure the Access Network and beyond, giving the subscriber a peace of mind.

Call Flow and Specifications
LIStrunk to LIStrunk (E1/T1 to E1/T1)
The system operates the E1/T1 interface as a 30/24 individual time slot of voice information. The output port leaving one corporate destination is designated to input port of other corporate, and the 64K is encrypted / decrypted after ADPCM compression. The total call setup time is about 1.5 sec. While the round trip delay is less than 60msec.The secure connection is between one LIStrunk to another. Note that Data call is NOT SUPPORTED, only Voice or Fax. Please refer to system description.

LIStrunk to LIScell or LISphone
In cases where the destination of the call is a client OUTSIDE of the corporate environment, located anywhere in the Public Switched Telephone Network, the LIStrunk maintains the Security by using LISphone or LIScell unit which encrypts/decrypts the call at the destination location. The system compresses voice to 8 Kbit/sec (G-729A) for LISphone and 6.4/5.3Kbit/sec (G723.1) for LIScell while retaining a high voice quality (toll quality) and uses fax relay for fax transmission. The total call setup time is about 6 to 7sec. While the round trip delay is less than 100msec for LISphone and about 400msec for LIScell due to the GSM network constrains.

Product Benefits:
LIStrunk provides solutions for the following issues:

• Privacy to run your business
• Secure encrypted cell communications providing peace of mind
• Easy to use and user friendly Interface
• Rapid deployment - comes completely configured - no need for setup.
• Uses latest popular cellular phone models
• Expandable to communicate with land lines!
• Manageable solution with unlimited scalability