Click for homepage
Elcrodat 6-2
ISDN Voice and Data encryptor

The Elcrodat 6-2 is a speech and data encryption device for ISDN telephone lines, developed by Rohde & Schwarz (R&S) in München (Germany) in the early 2000s. Is is the successor to the Elcrovox series initially developed by Siemens and is approved for TOP SECRET information. The Elcrodat series was developed by ANT (later: Bosch) in Backnang (Germany) before R&S took over.

The Elcrodat 6-2 allows voice data, fax messages and computer data to be transmitted securely over standard ISDN telephone lines. It is fully TEMPEST approved and is currently used by the German Government (2014) for voice/data communication at the highest security level.

A minimum installation consists of two or more Elcrodat 6-2 devices, a management station for certificate administration, a service station for remote administration and a logging station for remote monitoring of the encryption units. The image on the right shows a typical Elcrodat 6-2.
Elcrodat 6-2 with smart card

The unit is intended for desktop use and has a curved top surface with all controls at the front. At the right is 12-button telephone keypad plus 8 more control buttons. A large 4-line LCD screen at the left is used for interaction with the user. At the bottom right is a slot for a credit card-size authentication key. The Elcrodat 6-2 is the first encryption product approved for TOP SECRET that used Public Key Encryption (PKE) for key distribution. New keys are negotionated for each session.

Elcrodat 6-2 Elcrodat 6-2 with smart card Front view Close-up of the keypad Elcrodat 6-2 also known as ED6-2 Card slot
1 / 7
Elcrodat 6-2
2 / 7
Elcrodat 6-2 with smart card
3 / 7
Front view
4 / 7
Close-up of the keypad
5 / 7
Elcrodat 6-2 also known as ED6-2
6 / 7
Card slot
7 / 7
7 / 7

    Suitable for Euro-ISDN basic rate access (S0 bus/port). Allows 2 data channels to be encrypted independently. Maximum data rate 128 kbps.

    Special version for Euro-ISDN primary rate access (S2M port). Allows 30 data channels to be encrypted independently. Maximum data rate 1920 kbps.
Operation of the Elcrodat 6-2 is rather straightforward and involves only a few key-presses. All connections and indicators are at the front as show in the image below. Interaction with the user is via the large 4-line LCD screen at the left and the rubber push-buttons at the right.

The Elcrodat 6-2 is protected by a chip card in combination with a Personal Identification Number (PIN). For the encryption and decryption of information a (secret) algoritm is used which is based on a combination of asymmetrical and symmetrical encryption. For key exhange and authentication, the system uses an asymmetrical elliptical curve Public Key Encryption (PKE) technique. The actual data is encrypted with a proprietary symmetrical encryption algorithm developed by the Bundesamt für Sicherheit in der Informationstechnik (BSI) [2].

The Elcrodat 6-2 was approved by the for all security levels up to (and including) TOP SECRET and is the main encryption device used by the German prime minister Angela Merkel (2014). The device is also used by NATO and is probably the first PKE device that was approved by NATO.

  1. Rohde & Schwarz, ELCRODAT 6-2
    January 2009. Retrieved March 2014.

  2. BSI, Systembeschreibung ElcroDat 6-2
    German. Date unknown. Retrieved April 2014.
Further information
Any links shown in red are currently unavailable. If you like the information on this website, why not make a donation?
Crypto Museum. Created: Wednesday 02 April 2014. Last changed: Tuesday, 27 March 2018 - 07:12 CET.
Click for homepage