Melbourne, 15 May 2006
Siemens has developed the world's first cordless telephone with encryption technology. The Gigaset SL74X makes phone calls tap-proof and at the same time has the convenient features and the voice quality of a DECT telephone.
With technical equipment and the required know-how, it is becoming increasingly easier for unwanted listeners to hack into an unprotected telephone line. Companies that deal with strictly confidential information, particularly in the financial and technological sector, are therefore increasingly relying on devices with encryption technology.
In the encryption telephones that have been used up to this point in fixed-line networks, a modem installed at the phone simultaneously records the analog conversation and digitizes it. The little box equips this information with a 1024-bit key and then sends the digital data packet through the landline along with an identification code to the person on the other end. The recipient enters the usually four-digit code he sees on the telephone display into the keypad of his phone to decrypt the conversation before he accepts the call.
Siemens Home and Office Communication Devices has moved the small digital signal processor (DSP) that contains the encryption technology into the mobile handset of a Gigaset telephone, thereby making the radio link between handset and base station secure as well. And the DSP uses a key of 3072 bits, three times larger than its cord-equipped predecessor. The device will go on sale this fall for about 1,700 euros.
Despite the very efficient encryption, there is no loss in voice quality. Normally, placing tap-proof calls stretches the capacity of an analog landline to its limits because such lines are designed for voice transmission only. A conventional encryption telephone therefore reduces the voice data to a minimum — resulting in an unmistakable loss of voice quality. The DSP, on the other hand, filters out voice frequencies that are practically inaudible for the human ear. That reduces the quantity of data transmitted without diminishing the quality, a technique similar to the compression of music in MP3 files.
Press pictures are available at www.siemens.com/com-pictures/sl74x