Guaranteeing the ownership or copyright of digital communication is of extreme importance in this digital era. Watermarking is the technique which confirms the authenticity or integrity of communication by hiding relevant information in specified areas of the original signal such that it might render it difficult to distinguish one from the other. Thus, the digital watermark can be defined as a type of indicator secretly embedded in a noise tolerant signal such as image, audio or video data.

The paper presents a voice signal authentication scheme by employing signal features towards the preparation of the watermark and by embedding it in the transform domain with the Walsh transforms. Watermark used in this technique is unique for each member participating in this communication system and makes it is very imperative in the context of signal authentication.