DR 09-0294 — OPC: Embedded packages and pack IRI references

[Chris Rae]

http://cid-c8ba0861dc5e4adc.office.live.com/view.aspx/Public%20Documents/2009/DR-09-0294.docx

This DR asks whether a pack IRI can support a reference to an OPC part embedded in an embedded OPC package. We've done a bit of investigation here and it looks like it is indeed syntactically valid for a pack IRI to point to a part in an embedded package. However, allowing this in the standard would require a wholesale review of relationships and packaging concepts because none of these sections were written with the intent of pack IRIs pointing to "sub-packages". I don't know about other implementations but I can tell you that MS Office is not happy at all if you use these types of embedded pack IRIs.

Could we resolve this DR by adding a comment that pack IRIs cannot point into embedded packages? It would clear up the standard as it stands and, if we decided to invest efforts in this area later, we could always modify the text to add the feature.

Chris