San Diego-based Verimatrix, a developer of content security technology for the IPTV market, said Monday that the firm has signed on Bharat Sanchar Nigam Ltd (BSNL), an Indian IPTV operator, as a customer. Financial impact of the deal was not disclosed. Verimatrix said that the firm's Video Content Authority System has been deployed as part of a nation-wide IPTV launch. Verimatrix develops digital watermarking products used in set-top boxes to trace digital video, to prevent re-broadcasting and copying of that content. Verimatrix is venture backed by JK&B Capital, Goldman Sachs, and SunAmerica Ventures.