This chapter specifies the OPC UA Information Model for a Security Key Service (SKS). The functionality and behaviour of an SKS is described in 5.4.3. It defines the distribution framework for cryptographic keys used for message security.

The SKS can be a network service used to manage keys for all Publishers and Subscribers or it can be part of a Publisher to manage the keys for the NetworkMessages sent by this Publisher.

Figure 34 depicts the ObjectTypes and their components used to represent the PublishSubscribe Object.

Figure 34 – PublishSubscribe Object Types Overview

The PublishSubscribe Object is the root node for all PubSub related configuration Objects. It is an instance of the PubSubKeyServiceType or the PublishSubscribeType and a component of the Server Object.

The PubSubKeyServiceType defines the Method for access to security keys and the related management of SecurityGroups. This ObjectType is used for the PublishSubscribe Object if only the Security Key Service functionality is provided. If the PubSub configuration functionality is provided, the PublishSubscribeType is used instead.

The SecurityGroups are organized by the SecurityGroupFolderType and represented by instances of the SecurityGroupType.

The PublishSubscribeType contains the entry points for the PubSub configuration model defined in clause 9.