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Some XCON ideas. Henning Schulzrinne Dept. of Computer Science Columbia University hgs@cs.columbia.edu. Assumptions. Avoid transactions and similar constructions difficult to implement request is atomic Map closely to existing conference data structures
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Some XCON ideas Henning Schulzrinne Dept. of Computer Science Columbia University hgs@cs.columbia.edu IETF63 - XCON
Assumptions • Avoid transactions and similar constructions • difficult to implement • request is atomic • Map closely to existing conference data structures • avoids having to maintain two similar, but different structures • use superset of existing structure • Avoid two-level mechanism • Re-use well-known RPC mechanism • Use inheritance (no templates) • closely related concepts – confusing to have both • Affinity to CCCP, but further simplified IETF63 - XCON
Avoid two-level design “dial-out user” adds little abstraction depth get/set/delete something IETF63 - XCON
Re-use RPC • No need to design yet another remote procedure call (RPC) mechanism • Use SOAP – not prettiest, but by far the most popular • clients, servers, tools available in just about any language and OS • don’t know about Fortran and COBOL • well-understood by developer community • no need for protocol-level testing IETF63 - XCON
Example • Does not include standard SOAP header • e.g., addConference <conference-description> <subject>XCON</subject> <service-uris> <entry> <uri>http://example.com/</uri> <purpose>web-page</purpose> </entry> </service-uris> </conference-description> IETF63 - XCON
Operations (~CCCP) • add/change/get/deleteX • Conference • User • Endpoint • Media (for all users) IETF63 - XCON
Open issues • For adding users, can request fail partially • may want to add lots of users at once • add some users, but not others • generally want to proceed even if one user fails • can find out who got added by description returned IETF63 - XCON
What’s missing? • Simple start/end time property for conference • no repeats or the like • Conference media mixing • add floor control property to media • add moderator(s) to user property • define some standard algorithms for now • tiled: ““video follows audio” • no video mixing: “individual” • extend later • define video matrix • (label, width, height) IETF63 - XCON