Commit 6b14af7d authored by Jason Fox's avatar Jason Fox
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Clarify Auxilliary Registrations Behaviour

parent eebe97d6

md/clause-9.md

+27 −5
Original line number Original line Diff line number Diff line
@@ -37,11 +37,6 @@ kind of context data a [Context Broker]{.HTML-Keyboard} can exchange such as 
Entity IDs, entity types, attribute names, geofenced areas, etc. Ultimately, all

Entity IDs, entity types, attribute names, geofenced areas, etc. Ultimately, all

constraints specified in the registration shall be respected.

constraints specified in the registration shall be respected.





When a [Context Source]{.HTML-Keyboard} is registered, an operation mode is

selected. This defines the basis for distributed operations and also defines

whether or not the [Context Broker]{.HTML-Keyboard} is permitted to hold context

data about the Entities and Attributes locally itself.



If two registered [Context Sources]{.HTML-Keyboard} are providing context data

If two registered [Context Sources]{.HTML-Keyboard} are providing context data

for the same Attribute, the Attribute instances can be distinguished by

for the same Attribute, the Attribute instances can be distinguished by

_`datasetId`_. The mechanism for determining which data shall be returned is

_`datasetId`_. The mechanism for determining which data shall be returned is
@@ -275,6 +270,11 @@ defined as ["federationOps"]{.HTML-Code}. 




### 9.3.1 Introduction

### 9.3.1 Introduction





When a [Context Source]{.HTML-Keyboard} is registered, one of four modes of

operation is selected. This defines the basis for distributed operations and

also defines whether or not the [Context Broker]{.HTML-Keyboard} is permitted to

hold context data about the Entities and Attributes locally itself.



### 9.3.2 Additive registrations

### 9.3.2 Additive registrations





For additive registrations, the [Context Broker]{.HTML-Keyboard} is permitted to

For additive registrations, the [Context Broker]{.HTML-Keyboard} is permitted to
@@ -347,6 +347,28 @@ conflict to the registration. In the case that multiple overlapping **redirect** 
registrations are defined, operations are distributed to all registered [Context

registrations are defined, operations are distributed to all registered [Context

Sources]{.HTML-Keyboard}.

Sources]{.HTML-Keyboard}.





### 9.3.4 Precidence of distributed operations



The presence of a matching **exclusive** [Context Source

Registration]{.HTML-Keyboard} indicates that no further local or distributed

operations shall occur on the specified Attribute of a given Entity. Operations

associated with an **exclusive** [Context Source Registration]{.HTML-Keyboard}

are always processed before any other local or distributed operations.



Distributed operations triggered by **inclusive** [Context Source

Registrations]{.HTML-Keyboard} can take place in parallel to local operations.

When retrieving Entities, the algorithm defined in clause 8.5.3 shall apply in

case of conflict. **redirect** operations are similar, but no actions shall take

place within the local [Context Broker]{.HTML-Keyboard}.



**auxiliary** [Context Source Registrations]{.HTML-Keyboard} only apply during

context information consumption operations, and any distributed operation

asociated with an **auxiliary** [Context Source Registration]{.HTML-Keyboard}

shall only be triggered if no matching data has been received from all

previously encountered [Context Sources]{.HTML-Keyboard}, so that the

possibility of data retrieval from local and all other matching distributed

[Context Sources]{.HTML-Keyboard} has been exhausted.



## 9.4 Matching Context Source registrations

## 9.4 Matching Context Source registrations





When querying [Context Source Registrations]{.HTML-Keyboard} as described in

When querying [Context Source Registrations]{.HTML-Keyboard} as described in