The NAP Statement of Health (SoH) message is generated by a System Health Agent (SHA) and is used to represent a snapshot of one or more aspects of a client's health state (for example if Antivirus is installed and enabled).

These Statement of Health (SoH) messages are grouped together into a System Statement Of Health (SSoH) message that represents the aggregate of all known aspects of the client's health. The SSoH message is then sent within other protocols such as PEAP so that the PEAP end-point or Quarantine Server can evaluate the overall client health by passing each SoH from the SSoH to the appropriate System Health Validator (SHV).

The SHVs validate the SoH to determine whether the client machine is compliant with its sub-policy. Using the responses from the SHVs, the Quarantine Server determines if its overall policy is satisfied. Based on the result, the Quarantine Server then produces a System Statement Of Health Response (SSoHR) that contains the overall Quarantine State (QSTATE) and the Statement Of Health Responses (SoHr) from each of the System Health Validators (SHVs) that were evaluated as part of the policy evaluation.

The SoH and SoHr messages are transmitted between the SHA and SHV via a variety of methods depending on the enforcement technology. For example, PEAP has been extended to allow the SoH and SoHr messages to be exchanged as part of tunnel establishment.

For Microsoft licensing information, see Published Protocols and Royalty-Free License on Microsoft Developer Network (MSDN).