Mountain View, Calif.--VeriSign, the world's top provider of Internet trust services, has agreed to acquire Redwood Shores, Calif.-based Signio, a provider of b-to-b and business-to-consumer Internet payment software. The acquisition gives VeriSign, which provides authentication and validation software, an entre into the booming b-to-b Web payment sector. VeriSign will issue approximately 5.6 million shares of VeriSign common stock for all of the issued and outstanding capital stock of Signio and will assume Signio's outstanding employee stock options. The acquisition will be accounted for as a purchase transaction. No other financial details of the pact were disclosed.