VeriSign VP of authentication services Mark Griffiths said that under current Microsoft PKI deployments the chain of trust only goes as far as the certificate authority within the enterprise in which it is deployed.

When chained to VeriSign, companies will be able to tie their Microsoft-based PKIs together, Griffiths said. He emphasized, however, that VeriSign believes this is approach is less cost effective than just buying the whole PKI from VeriSign.