The service behaviour is in accordance with the patterns detailed in Message Exchange Patterns: Identification Guidelines. A combination of an AMQP 1.0 implementation and an OGC Web Feature Service 2.0 Interface Standard implementation is used. Regarding message exchange patterns the service consists of- SYNCHRONOUS_REQUEST_REPLY - RESTful interfaces handle the subscription and request for Digital NOTAM.- BROKERED_PUBLISH_SUBSCRIBE_WITH_PUSH_MECHANISM - an AMQP 1.0 implementation handles the distribution of the messages. The behaviour of Digital NOTAM Subscription and Request Service Subscription Interface under normal conditions: - The service consumer sends RESTful request message to subscribe (subscription request contains valid filter)- The service consumer remains blocked while awaiting the reply- The service remains blocked while processing the reply- The service sends response message with AMQP Queue name, subscription filters and subscription status to the service consumer (subscription is by default created with status "PAUSED", i.e. subscription will not receive any Digital NOTAM messages yet)- The service consumer sends RESTful request message to activate subscription- The service consumer remains blocked while awaiting the reply- The service remains blocked while processing the reply- The service sends response message to the service consumer, informing about subscription status change The behaviour of Digital NOTAM Subscription and Request Service Distribution Interface under normal conditions: - event scenario is triggered, this causes change of aeronautical data in the system- the system generates Digital NOTAM message- the system distributes the message to AMQP Queues based on subscriptions and their stored filters (handled by AMQP Message Broker) - the service consumer connects to their AMQP Queue and consumes the message- the service consumer sends acknowledgement to AMQP Message Broker, the message is removed from the queueThe behaviour of Digital NOTAM Subscription and Request Service Request Interface under normal conditions: - The service consumer sends RESTful request message with WFS GetFeature query- The service consumer remains blocked while awaiting the reply- The service remains blocked while processing the reply- The service sends response message with data.