Subscription and Notification Pattern

Is used by Doing Business Abroad Pilot in Use Case "Doing Business in Another Member State" (DBA UC2)

Introductory text

Functional Variants of the Subscription and Notification Pattern

Two distinct business requirements for Subscription and Notification Pattern: Updating of previously shared Evidence or being informed about an Event

Technically also two different approaches to Notification: Sending updated Data of a defined Evidence type or Event Notifications that contain only the identification data and the event type. Technical approach and business requirement do not relate one two one, giving rise to potential hybrid approaches.

Event The reference Architecture for the DE4A projects focusses the Subscription and Notification Pattern on Event Notification, which can be combines with the Lookup Pattern to cover the updating previously shared evidence use case. [23-04-2021: tables below still represent a hybrid approach and need rework]

Delimitation to BRIS (DBA specific)

As concluded in “DE4A Discussion paper BRIS 20200708 Final.docx” BRIS will not be used in the DBA pilot. This also applies for the subscription and notification pattern. The notifications send resorting under BRIS regulation are out of scope of DE4A. The DE4A pattern has its own subscriptions and notifications that do no relate to BRIS regulation. Note that in some cases this could lead to the situation that a Data Evaluator receives both a BRIS and a DE4A notification for one business event.

Note the BRIS proposed change in the technical working group: Subscription will be replaced by a push notification through registering international branches in the registry of the mother company. Thereby reversing the responsibilities.

Business Process

Event Subscription

Business Process

Activity Table

Activity / UC	Role	Type*	Description
Trigger initiate subscription	Public Service Procedure	User	A procedure of a public service provider leads to the registration of a subject. After this registration events can occur to the subject that could have impact on the service delivery to this subject. In order to be informed on these events, the public service provider can subscribe to the life-events or business-events of the subject. The  subscription process can also be triggered for technical reasons: for instance to resend failed subscription requests. In the pilot Doing Business Abroad the subject is the represented company itself or a new branch of the represented company (the parent-company of the branch) and Data Evaluators subscribe to be notified on the business events of the represented company. Note: subscriber should unsubscribe and re-subscribe if participant-id changes. To be able to do so, subscriptions have to be registered at the DE.
Initiate subscription	DE	Service	To initiate the subscription data is collected and the subscription need is formulated: subject identifier data owner identifier subscriber identifier event catalogue action 'subscribe' subscription start and end date The subscription need is forwarded to the Data Requestor (if applicable).
Trigger cancel subscription	eProcedure / Public service / Notification	Service	Potential triggers to cancel a subscription are: Public service: public service delivery can lead to the need to cancel the subscription (the public service has ended, e.g. a multi-year subsidy procedure, the country can decide to cancel the  branch-office registration). eProcedure: the user can also withdraw from service and thereby initiating cancellation of the subscription. Notification: after receiving a notification the assessment can be that the subscription is no longer needed (exception flow). Technical reasons: for instance an error at the DO-side could lead to the need to resend the request to cancel a subscription.
Cancel subscription	DE	Service	To cancel a subscription data is collected and the cancel subscription need is formulated: subject identifier data owner identifier subscriber identifier event catalogue action 'cancel subscription' subscription end date The cancel subscription need is forward to the Data Requestor (if applicable).
Lookup event provider routing information	DR	Service	The DR uses the data owner identifier to look up routing information on the competent authority that facilitates subscription service.
Inform National Contact point that un-subscription was not successful	DR	User	In case of the cancellation of a subscription there is a slight chance the participant ID of DO has changed: a manual process deals with this (unhappy) flow.
Send (un)subscription request	DR	Service	The request to subscribe or unsubscribe is send to the participant facilitating the subscription service using the previously retrieved routing information. The subscription / cancel subscription request contains: the participant id of the subscriber, the subject identifier, the event catalogue, the period of subscription and the requested action (subscribe / cancel subscription).
Forward (un)subscription error	DR	Service	The (un)subscription error message received from Data Transferor is forwarded to the Data Evaluator.
Investigate reason for (un)subscription error	DE	User	The received error message is analysed and appropriate actions are taken. This exception flow is not further detailed in this design.
Forward confirmation	DR	Service	The confirmation on the (un)subscription request (received from the DT) is forwarded to the Data Evaluator.
Log (un)subscription information	DE	Service	The confirmation is logged to complete the audit trail. Note: register in a way that it is easily readable (optional: include subscription id).
Validate (un)subscription request	DT	Service	The request is validated on a technical level: xml validation and check on DE authorisation. If the request validates it is forwarded to the Data Owner. Technical exceptions are out of scope.
Evaluate (un)subscription request	DO	Service	The (un)subscription request is evaluated to check if the request can be completed: Subscription functional checks: does subject exists, is event catalogue supported. Cancel subscription functional checks: does subscription exists. If the request does not pass the functional checks, the request is rejected and an error message will be send.
Prepare (un)subscription error message	DO	Service	Collect the content of the error message and send it to the Data Transferor (if applicable). The (un)subscription error message contains: participant id of subscriber, subject identifier, requested action, reference to the request message, full request message and the errorcode.
Send (un)subscription error message	DT	Service	The error message is forwarded to the Data Requestor from who the request was received.
Register (un)subscription	DO	Service	The Data Owner creates, changes or ends the subscription according the (un)subscription request.
Confirm (un)subscription	DO	Service	The confirmation of the (un)subscription is created and send to the Data Transferor (if applicable). The confirmation message contains: (un)subscription result (success), timestamp of (un)subscription, (un)subscription request reference, original (un)subscription request message.
Send (un)subscription confirmation	DT	Service	The (un)subscription confirmation is send to the Data Requestor from who the request was received. The (un)subscription confirmation message is added to the log.

Design decisions

Explicit request and preview

The nature of the subscription and notification pattern leads to a different use of the explicit request and preview as stated in the SDG-regulation:

• Notification is performed without a user transaction, making real-time explicit request and preview impossible.
• Fraud prevention outweighs user centricity, making explicit request and preview less opportune.
• The public nature of company data relaxes the need of explicit request and preview.

Implementing an explicit request for future notifications introduces the burden of creating and maintaining an explicit request administration, with for instance options to retract a previously given explicit request

Design decision: for the Business event notification explicit request and preview as defined in the SDG-regulation is not applicable.

Positioning of subscription registration

For the location of the subscription registration certain options can be considered:

• Fully at the data providing MS: The subscription is registered at the data providing member state. The DE sends messages to the DO via DR and DT to manage the subscription (subscribe, cancel subscription).

• Splitted between data provider and data consuming MS: It is a possibility to split the register; the DO then only registers which MS subscribe to a certain company, and the DC MS registers which DE subscribe to the company. The process flow would be: (1) a central component at the DT registers which DE’s subscribe to which subjects of which data owners; (2) the DT registers as a MS for this company; (3) the DO registers which MS subscribes to which company and sends notifications to the DT (4) the DT distributes the notification to all DE.
• At a central component: The DE4A-architecture implements the four-corner model, a central subscription register would conflict with this principle. Moreover, a subscription is a direct relation between a DO and a DE regarding a subject, there will be no added value to place such a subscription in an external, central component.

Design decision: The registration of subscriptions is placed within the data providing member state. DP MS is free to choose in which environment this is (DT, DO or another environment). The assumption for the design of the S&N pattern is that the subscription registration is fully placed in the environment of the DO.

Subscription period

Including a subscription period with start and end date has several consequences... todo

Design decision: a subscription period with mandatory start and end dates is included in the subscription.

Catalogue of DE4A business events

tbd, see table below

Subscription register requirements

Evidence exchange and subscription request

The main flow of the DBA-pilot is that the intermediation pattern triggers the subscription and notification pattern. Part of the intermediation pattern is the exchange of evidence: DE requests a specific evidence type from a specific company from the DO. In the happy flow the DE subscribes to receive notifications regarding this company. This trigger can be implemented in different ways:

• As a part of the request for evidence. The evidence exchange request then consists at least of: company identifier, requested evidence type, DE identifier, subscribe y/n.

• In a separate subscription request message: after a user consent to the preview and a successful completion of the registration process a separate subscription message is sent.

Design decision: the subscription request is not combined with the evidence exchange request but is sent after successful registration of the company/branch.

Combining the subscription request with the evidence exchange would be too early in the process. It would lead to (possibly a relative high number of) requests to cancel the subscription if no consent was given or the registration was not successful. This would also introduce the risk of unauthorised subscriptions and notifications if the cancellation fails.

There are two main choices for the subscription criteria, subscribe to changes in:

• business events
• evidences

Design decision: not all business events are related to an evidence, subscriptions must therefore be made to business events to cover all notifications to be sent, see table below.

Business event - evidence mapping

Below example for Doing Business Abroad Pilot. Each pilot (domain) must define their common event list including a clear semantic explanation of each business or life event in order for the Data Evaluator to be able to interpret the event correctly and define an appropriate course of action, e.g. request an updated evidence or discontinue the public service.

DE4A Business event	Event includes changes in	Related evidence type	Comment
Company info event	EUID, Updated company name/updated address/updated head quarters/changed identifier (EUID)/changed legal form/changed representatives	Company registration	Split this event in: address change, name change, ...? And with a status change, notify the specific status?
Annual report event	Annual reports	Annual report	What is the event? New annual report available, annual report changed, ...? Split this event?
Directors disqualification event	Disqualifications updated for directors	Directors disqualification
National merger event	Merger initiated/completed/cancelled, transferring company identifier, aquring company identifier		Notifications are only relevant when the transferring company has subscribers.
Cross border merger event	Merger initiated/completed/cancelled, transferrring company identifier, aquaring company identifier		Notifications are relevant when the transferring company has subscribers. This event is also relevant without a subscription. The business register of a company involved in a merger wants notifications even if there is no prior subscription to the foreign company in the cross border merger.

Event Notification

Business Process

Activity Table

Activity / UC	Role	Type	Description
Trigger Change in registered company	Company representative / SP	User	An event - business event or life event - occurs for the subject and this triggers the notification process. For the pilot Doing Business abroad the subject is the represented company. Business events impacting the company can be initiated by: a representative of the company itself, e.g.: merger, change of owner. a public service, e.g.: change of postal code, death of representative, court of law ruling.
Change company registration	DO	User	Standard process of the Data Owner - Business Register - to process changes in company registration as a result of the business event. NB is this action really in scope of the event notification process?
Identify event	DO	Service	The Data Owner determines the event identifier. Note that the DO must have a mapping of it's own business events to the list of DE4A business events.
Check subscription	DO	Service	The subscription register is queried for subscribers to the subject related to the event: No active subscriptions: end of process Active subscriptions for the DE4A event catalogue found: continue notification process Other active subscriptions found: trigger relevant process(es)
Prepare notification message and subscriber list	DO	Service	Make a list of the subscribers to notify and create the payload of the notification, mainly the DE4A business event name and the timestamp the event took place.
Resolve service metadata	DT	Service	Single notifications messages (one for each subscriber) are created from the list of subscribers and the notification payload. The routing information for each notification message is looked up. The messages contain: subject identifier, secondary subject identifier (in case the identifier changed), subscriber identification, event identification, event timestamp, subscription reference (optional).
Resolve subscriber participant ID and inform National Coordinator	DT	User	If address / DE participant id is not found in the metadata, manual action is needed: contact DE / MS of participant id to analyse the exception and take appropriate measures.
Request from DE to resend event notifications	DE	User	Exception flow for missed notifications (failed or non-failed): if a DE misses notifications a resend of notifications can be requested.
Resend past event notifications	DT	User	The resending of previously sent notifications requires a manual action at the DT.
Send event notification	DT	Service	The event notification is send to the Data Requestor, a technical acknowledgement that the notification has been received by the DR is received. The audit log is updated with both the event notification and the acknowledgement.
Validate event notification	DR	Service	The Data Requestor performs a technical validation of the event notification and forwards it to the Data Evaluator. A technical exception flow is out of scope of this process description.
Determine event response	DE	Service	The notified event is analysed and the appropriate response is determined. The determination result is logged as a part of the audit trail: Subject identifier Notified event Request id Determined response Timestamp of determination
Request unsubscription	DE	Service	When the company cannot be identified or the registered company or branch is no longer active the cancellation of the subscription is requested. Afterwards this will be analysed to find the cause of this apparently wrong subscription and to take appropriate measures.
Dismiss event	DE	Service	The notified event doesn't have impact on the procedures of the Data Evaluator and is dismissed. No further actions need to be taken.
Evidence update event triggered	DE	Service	The lookup pattern is triggered to request a new, current, copy of the relevant evidence. The pilot Doing Business Abroad will request the Company Registration Evidence.
Identify business responses and notify responsible party	DE	User	The responsible organisational unit is identified and informed in order to take appropriate action. It depends on the specific process if this action can be performed automated or manually.

Design decisions

Response on event notification

Functional responses from Data Evaluator to Data Owner after receiving an event notification, for example to inform that appropriate actions have been taken, are out of scope of the Subscription and Notification pattern.

Notifications from Subscriber

Notifications from Data Evaluator to Data Owner, for example to inform Data Owner on changes in the branch registration, are out of scope of the Subscription and Notification pattern.

Process Realisation

?All on one Page or do we create sub-pages for Business Process and Process Realisation?

Used by the following use cases

DBA (UC2)

Application collaborations

TBD