Background

The ebXML Message Service (ebMS) specification version 2 states: The value of a CPAId element MUST be unique within a namespace mutually agreed by the two parties.

The NEXUSe2e developers interpreted this to mean that the scope of any CPAId's uniqueness may be in the context of two trading partners, as long as the parties agree. Developers of one or more other messaging systems require globally unique CPAId values, regardless of a mutually agreed more narrow namespace.

Work-Around Description, Submitted by Simplot

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Excerpt from the ebMS 2 specification regarding CPA ID: “The value of a CPAId element MUST be unique within a namespace mutually agreed by the two parties”parties.”.

CPAId is usually a concatenation of the two trading partner party IDs.  “CNInvoice” or “GenericFile” alone is more like a service or action value than a CPAId, and violates the ebMS 2 specification.  Adding party IDs to the CPAId like they are doing (e.g. uri://nexuse2e/Cleo/GenericFile) in essence makes it a unique ID between two parties.

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