1. RESTful CSSM?

2. REST REST is not just no SOAP Operate on (state of) resources – In principle HTTP verbs PUT, GET, POST, DELETE – Similar to CRUD (Create, Read, Update, Delete) – Resource represents an object – Typically represented as XML doc As in Uniform Resource Identifier Not a functional resource – All Resources addressable by URI ~= Identity

3. Example Resources Resource IDs – https://cssm.esa.int/sa/service-agreement-id https://cssm.esa.int/sa/service-agreement-id – https://cssm.esa.int/profile/654321 https://cssm.esa.int/profile/654321 – https://cssm.esa.int/sa/service-agreement- id/profiles https://cssm.esa.int/sa/service-agreement- id/profiles

4. Examples QSA GET https://cssm.esa.int/sa/esa_nasa_sa_1https://cssm.esa.int/sa/esa_nasa_sa_1 -> serviceAgreement ATP PUT https://cssm.esa.int/sa/esa_nasa_sa_1/tp/tp_1https://cssm.esa.int/sa/esa_nasa_sa_1/tp/tp_1 – Body is profile as XML -> id of created resource (and other necessary info) https://cssm.esa.int/sa/esa_nasa_sa_1/tp/tp_1 25 …

5. References s1 s1 https://cssm.esa.int/sa/esa_nasa_sa_1/tp/tp_1 https://cssm.esa.int/sa/esa_nasa_sa_1/cp/Fwd2 https://cssm.dsn.nasa.gov/DSS-65 2008-04-12T00:00:00Z 2008-04-12T00:10:00Z true

6. Three-Phase Operations? Immediate return (like xxx-AR) – Acknowledges syntax, immediate checks etc. – Includes resource URI – Includes explicit state e.g. Requested – Includes expected disposition time State updated by CM – Notified to UM Resource (including state) can always be queried

7. Notifications? From CM to UM – return path Similar protocol possible POST https://cssm.esa.int/sa/esa_nasa_sa_1/notification/id https://cssm.esa.int/sa/esa_nasa_sa_1/notification/id – XML body e.g.

8. Mappings HTTP is obvious and easy SOAP REST also possible MO/MAL mapping would probably use COM

9. c.f. Document Exchange What do we lose? – Message sequence counts / checking Correlation seems not a problem – Multi-invocation packing – ???

10. c.f. Document Exchange What do we gain? – Less spec to write / maintain No new operations – At least one fully standard mapping (http) – Simpler implementation – Straightforward application to plain information entities Need to specify standard URL patterns

11. Miscellaneous thoughts Multi-way co-ordination (e.g. DDOR, handover) – URLs support possibility of refs between Multiple agencies Multiple SAs Support refs to non-CSSM resources? complex operations – E.g. ETP, ANT, SAS – How well do they fit resource model? – To be investigated