The recent thread between Jon and me has given me some added clarity as to the framing and scoping of the agreement problem space. Please consider the following as my view of how the agreement concept space is populated and which of these concepts are in or out of scope of WS-Agreement. Note, I have CAPITALIZED certain keywords that I think are the important concepts we need to tease apart. I thought this would be easier than reading HTML or LaTeX tags in the ASCII. :-) Do we have a concensus on these concept definitions and/or scoping? If so, I would be happy to try to rejigger the specification introductory text to better communicate this information. If not, I think it is crucial that we iterate on this until we do have consensus! karl In designing and presenting WS-Agreement, it is useful to define the concept space of agreement. 1. Agreement is a RELATIONSHIP between two parties. The core concept of WS-Agreement is that agreement is a relationship between two parties in which they are obligated to act in certain ways according to a notion of reciprocity. These obligations are necessarily domain-specific, and the reciprocity does not imply symmetry: one party may be obligated to complementary behaviors such as paying for service rather than returning service in kind. The semantics of this relationship are out of scope of WS-Agreement because they are domain-dependent. 2. WS-Agreement defines a PROTOCOL for establishing agreement. The fundamental resource management challenge being addressed by WS-Agreement is the standardization of a signaling protocol to allow temporary two-party agreement relationships to be established, maintained, and retired in a decentralized, multi-party, distributed system. These agreements modify, or parameterize, the behavior of the parties towards one another while respecting global system constraints on available resources etc. The mechanics and syntax of this protocol, except for the embedded domain-specific content, are within scope of WS-Agreement. 3. The WS-Agreement protocol encodes an agreement DOCUMENT which represents the nature of the relationship in order to facilitate agreement establishment. At minimum, WS-Agreement requires that one party OFFERs to establish agreement with an embedded agreement document. The other party must ACCEPT or REJECT this offer to establish (or not) the agreement relationship and bind the two parties. The syntax of this document, except for the embedded domain-specific content, are within scope of WS-Agreement. 4. The agreement document also is useful to represent the STATUS of the relationship for purposes of general system introspection and management. The presentation of the document and associated advisory metadata is within scope of WS-Agreement. 5. Another goal in some trust and accounting environments is to be able to DEMONSTRATE that an agreement relationship exists. The ability to demonstrate the existence of an agreement relationship may be valuable when resolving conflicts or in order to increase confidence in an agreement relationship between parties enjoying limited trust in one another. This demonstration of agreement can be facilitated by bilateral exchange of agreement documents with signature or some other means of visibility to a third party arbiter, whereas mere establishment of agreement between trusting parties may be accomplished with less data exchange. The ability to exchange agreement documents bilaterally is within scope of WS-Agreement, while the specifics of how one might sign such documents is out of scope and only supported through extension mechanisms. 6. Another goal is to be able to MEASURE the satisfaction of an agreement relationship. The measurement or validation of behavior of a party may be performed for different reasons by each party in the agreement and/or a third party. a) A party may measure its own behavior in order to adaptively stay within the terms of the agreement, to know whether it has done so, or to ADVISE the other party when the relationship cannot be satisfied. b) A party may measure the other party's behavior in order to RATE the reliability or trustworthiness of that party. c) A third party may AUDIT either party's behavior in order to facilitate resolution of conflicts (possibly in combination with demonstration of the agreement relationship). The self-monitoring behavior of an agreement party is out of scope of WS-Agreement, but the ability to advise other parties of past or imminent status changes is within scope. The monitoring of behaviors by the second or third party is out of scope of WS-Agreement. [Should an ability to advise a party of external observations of its behavior be in scope? It is not currently.] -- Karl Czajkowski karlcz@univa.com