Lawful interception system or system for authorized electronic monitoring enables interception of communications in the network, leaving the interception subject and his correspondents, network operators, service providers and access providers unaware that the interception is taking place.

TNC enables handover, acquisition and recording of interception results, and also their presentation in the form suitable for the current phase of investigation or law enforcement procedure.


  • Full monitoring - call contents and interception related information IRI
  • Statistical monitoring - interception related info only
  • Complies to relevant international standards and recommendations ITU-T, ETSI, ISO, IEC ...
  • Paralel operation upto 8 independent services or agencies authorized to perform lawful interception
  • Standard, generaly available input/output units and data formats
  • Electrical characteristics per ITU-T Q and G series
  • High reliability and immunity to external influences
  • Built-in self-check and diagnostic functions
  • Modular internal construction enables easy expansion or reconfiguring


  • Lawful interception in fixed public switched telephone network
  • Lawful interception in mobile telephone network
  • Lawful interception in special / private / closed network
  • Law Enforcement Monitoring Facility LEMFas defined in ETSI recommendations


  • Supports proprietary architectures and specifications not compatible with ETSI standards
  • Technically unlimited number of targets
  • High level of data protection, both collected and processed data, and high level of system protection
  • Simultaneous independent interception of the same communication by several services or agencies
  • Advanced processing of interception results through integration of third-party tools
  • Fully software programmable intefaces
  • Advanced and user-friendly Graphic User Interface simplifies operator work

Open TNC architecture is suitable for heterogeneous network that contains ETSI compatible exchanges, SRCE exchanges and ETSI incompatible exchanges. Integrated TNC architecture enables handover of call contents and interception related information over the same transmission media.

Lawful interception system TNC is a state-of-the-art, highly professional system, featuring exceptional electrical characteristics, user-friendly concept and high reliability. Thanks to many adjustable and programmable features, TNC easily copes with customer special requests.

System TNC is designed for international market and is available in english, russian and serbian language versions.

Along with other GVS products, like switching systems, uninterruptable power supply systems, test & measurement equipment and others, TNC offers a complete, well composed solution and forms a one-stop-shop for all telecom equipment for your telecom network node.

Technical data

Network intefaces

  Compliance   ITU-T G.703 E1
  Bitrate   2048 kbps ±50 ppm
  Line coding   HDB3
  Impedance   120 Omega, twisted pair / 75 Omega, coax.
  Overvoltage protection   ITU-T K.41
  SS7 level 2/3   MTP Q.701 - Q.709
  SS7 level 4   ISUP Q.761 - Q.764
  DSS1 signaling   ITU-T Q.93x
  Data transmission   100BT, TCP/IP
  HI interface   ETSI ES 201 671

User interfaces

  Analog telephone   Z, Q.55x, 64 kb/s
  Analog line   Z inv, Q.55x, 64 kb/s
  Overvoltage protection   ITU-T K.20

System intefaces

  Operation & maintenance   LAN, 100BaseT
  System printer   Laser A4
  Input/output units   FDD, CD, DVD
  Alarm panel   RS-232, RS-485
  Power supply   48 V, A - ETSI ETS 300 132-2
  Optional power supply   220/230 V ac


  Analog ports   80 @ 1 E
  Acquisition channels   480 @ 1 E 16 x E1
  Operator workplaces   100

Call contents

  Interception   with or without call release
  Handover   HI3, ETSI ES 201 671
  Acquisition   added/quasi stereo
  Monitoring   real-time or VoIP
  Forwarding   PCM 64 kbps or VoIP
  Audio delay   < 250 sfmusec
  Recording   PCM16, PCM8, A/ mu, FLAC
  Playback   integrated
  Basic processing   integrated

Interception related information

  Handover   signaling channel
  Handover format   HI2, ETSI ES 201 671
  Data acquisition   correlating
  Monitoring   real-time
  Forwarding   e-mail, SMS, IM
  Recording   ISO/IEC 26300, XML, ODBC
  Statistical processing   integrated


  Compliance   ETSI TS 101 331
  Administration   HI1, ETSI ES 201 671
  Intercept admin.   single or group
  User administration   operators, permissions
  Results presentation   integrated
  Advanced processing   external tools
  Results exporting   generic/processed
  Export format   ISO/IEC 26300, MP3, PDF


  Functionality   ITU-T G.823, Q.541
  Clock absolute accuracy   2x10 -10
  Temperature stability   10 -10

Electrical characteristics

  Audio transmission   G.712, G.507
  Attenuation   7 dB -0,3 +0,7 @ 1020 Hz
  Non-linear distorsion   ±0,5dB -55 +3dB mo
  Crossover attenuation   >73dB @1020Hz
  Psophometric noise   < -72 dB m400 pW
  Non-psoph. noise   < -40 dB m100 000 pW
  Intermodulation   <-41dB m0@ 900/1020Hz
  Overload point   3,14 dB m0@ 1000Hz
  EM compatibility   ETSI EN 300 386

General data

  Temperature range   0 oC to 40 oC
  Storage temperature   -20 oC to 60 oC
  Relative humidity   0 to 90 %
  Board dimensions   PC AT
  Cabinet dimensions   23", 2,15 m
  Acoustic noise   ETSI ETS 300 753
  Documentation   CEPT T/CS 01-10E

Reliability and maintenance

  Service life   40 years
  Spare parts & repair   10 years
  Fault detection   automatic, 50-200 msec


Document Title




TNC System Fact Sheet



521 K