DDSI-RTPS 2.5 RTF Avatar
  1. OMG Issue

DDSIRTP25 — Unclear specification on how the Publisher GUID is communicated

  • Key: DDSIRTP25-4
  • Status: open  
  • Source: Real-Time Innovations ( Gerardo Pardo-Castellote)
  • Summary:

    The specification uses a field called remoteGroupEntityId (see Table 8.67) to identify Publishers and Subscribers.

    Furthermore it specifies that this s communicated using a PID_ENDPOINT_GUID.

    It seems that this is related to PID_GROUP_GUID.
    But Table 9.14 says that PID_GROUP_GUID is "reserved for future versions"

    The relationship between this should be clarified.
    Furthermore the implementation of GROUP order and coherent access (8.7.5 and 8.7.6) require knowledge of which DataWriter belong to which Publishers. But how this is discovered is not specified.

    Minimally we should say that:

    A Publisher has a GUID that should be constructed from the GuidPrefix_t and an Entity_id.

    The PublisherGUID shall be communicated vis discovery using either a PID_GROUP_ENTITYID or PID_GROUP_GUID

    The WriterProxy::remoteGroupEntityId should contain the Publisher GUID

  • Reported: DDSI-RTPS 2.3b1 — Sat, 2 Mar 2019 19:57 GMT
  • Updated: Sat, 2 Mar 2019 19:57 GMT