PublicKeyInfrastructure (PKI) is a security mechanism often used in WebServices Implementations. Its use is also common in the setup of SecureSocketsLayer implementations (Layer 7 of OpenSystemsInterconnect model)
With adoption of OasisOrganization WebServicesSecurity (WSS) specification, PKI implementation become common amongst vendor products. This is because use of PKI mechanisms enabled easier "roll-your-own" SSL like mechanisms (with fine grained encryption and authentication) that conform with WSS and upcoming WS-SecureConversation, WS-Trust.
There exists a risk that has to be managed, due to vagueness in the application of the standards concerned.
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