None

  The entity (person or organization) that provides an appropriate agent, referred to as the “provider agent” to implement a particular Web service. It will use the provider agent to exchange messages with the requester’s requester agent. “Provider” is also used as a shorthand to refer to the provider agent acting on the provider’s behalf.
Source(s):
NIST SP 800-95 Web Services Architecture - W3C Working Group Note 11 February 2004

  A party that provides (1) a public key (e.g., in a certificate); (2) assurance, such as an assurance of the validity of a candidate public key or assurance of possession of the private key associated with a public key; or (3) key confirmation. Contrast with recipient.
Source(s):
NIST SP 800-56B Rev. 2
NIST SP 800-56B Rev. 1 [Superseded]