Table 17defines the parameters for the Service.

Table 17– ActivateSession Service Parameters







Common request parameters. The type RequestHeaderis defined in 7.28.



This is a signature generated with the private key associated with the clientCertificate. This parameter is calculated by appending the serverNonceto the serverCertificateand signing the resulting sequence of bytes.

If the serverCertificatecontains a chain, the signature calculation shall be done only with the leaf Certificate. For backward compatibility a Servershall check the signature with the full chain if the check with the leaf Certificatefails.

The SignatureAlgorithmshall be the AsymmetricSignatureAlgorithmspecified in the SecurityPolicyfor the Endpoint.

The SignatureDatatype is defined in 7.32.

clientSoftwareCertificates []


Reserved for future use.

The SignedSoftwareCertificatetype is defined in 7.33.

localeIds []


List of locale ids in priority order for localized strings. The first LocaleIdin the list has the highest priority. If the Serverreturns a localized string to the Client, the Servershall return the translation with the highest priority that it can. If it does not have a translation for any of the locales identified in this list, then it shall return the string value that it has and include the locale id with the string. See OPC 10000-3for more detail on locale ids. If the Clientfails to specify at least one locale id, the Servershall use any that it has.

This parameter only needs to be specified during the first call to ActivateSessionduring a single application Session. If it is not specified the Servershall keep using the current localeIdsfor the Session.


Extensible Parameter


The credentials of the user associated with the Clientapplication. The Serveruses these credentials to determine whether the Clientshould be allowed to activate a Sessionand what resources the Clienthas access to during this Session.

The UserIdentityTokenis an extensible parameter type defined in 7.36.

The EndpointDescription specifies what UserIdentityTokensthe Server shall accept.

Null or empty user token shall always be interpreted as anonymous.



If the Clientspecified a user identity token that supports digital signatures, then it shall create a signature and pass it as this parameter. Otherwise the parameter is null.

The SignatureAlgorithmdepends on the identity token type.

The SignatureDatatype is defined in 7.32.




Common response parameters (see 7.29for ResponseHeaderdefinition).



A random number that should never be used in any other request.

This number shall have a minimum length of 32 bytes.

The Clientshall use this value to prove possession of its Application Instance Certificatein the next call to ActivateSessionrequest.

results []


List of validation results for the SoftwareCertificates(see 7.34for StatusCodedefinition).

diagnosticInfos []


List of diagnostic information associated with SoftwareCertificatevalidation errors (see 7.8for DiagnosticInfo definition). This list is empty if diagnostics information was not requested in the request header or if no diagnostic information was encountered in processing of the request.