Method and apparatus for subscriber authorization and audio message integrity verification

摘要

In the method, to the traffic signal an additional watermark signal is added which is not audible at the presence of the traffic signal, and then the signal is transmitted on a telecommunication link to a subscriber, where it is received and decoded, as a result of which a Watermark Binary Signature and a first Hash Function are received. The Watermark Binary Structure is compared at the receiving side of the link with the declared by the subscriber Watermark Binary Watermark Structure. A second Hash Function is determined from the non-decoded received signal. The two Hash Functions are compared with each other in order to determine whether the audio message has been edited.

<Paragraphs id="pa02" num="0002" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">To the subscriber's terminal an Electronic Subscriber Module (EMA) is connected which comprises in its structure a transmitting line (1) and a receiving line (2) of an additional signal (SD), in which transmitting line (1) the following main functional blocks are provided: Hash Function generator (gFS) and a Watermark Binary Signature generator (gBSZW), as well as an Additional Signal Generating unit (uFSD), while in the receiving line (2) the following main functional blocks are provided: an Additional Signal decoder (dSD), a Hash Function decoder (dFS), and a Hash Function comparator (kFS).

<Paragraphs id="pa03" num="0003" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">The advantageous features of the invention are constituted by a function of secret identification of a subscriber and a function of verification of integrity of a traffic signal as a subscriber's audio message, based on the technique of marking traffic channel in telecommunication links. These two functions: subscriber identification and audio message integrity verification, are performed in a secret manner, at the background of the traffic signal, and thus the subscriber with a terminal without the described apparatus connected thereto will not be aware that he is being authorized as a subscriber, and moreover the method and the apparatus are independent from the telecommunication link infrastructure and they do not interfere with its internal components.