DDS15 — The compatibility rules for the Presentation QoS are too strict

The compatibility rules for the Presentation QosPolicy, specified in section 2.2.3.6 of the DDS Specification prevent a subscriber configured using GROUP access scope from simultaneously matching a publisher configured using GROUP access scope and a publisher configured using TOPIC or INSTANCE access scope.

Proposed Resolution:
The addition of a new boolean field called "use_highest_offered_access_scope" to Presentation QosPolicy.

This boolean is not propagated as part of the discovery information and remains local to the subscriber. Users configure the subscriber to the minimum accepted access scope. When the boolean field is set to true, the subscriber will provide the access_scope offered by the publisher as opposed to its own access_scope value.

For example: a subscriber wanted to provide GROUP access scope when matched with a GROUP order publisher and with a publisher providing INSTANCE access scope, will use INSTANCE access scope and set the user_highest_offered_access_scope boolean to true.