Hi Markus
ContactMedium is a ubiquitous sub-entity, which API designers have seen fit to attach to various entities in the Open API model.
It's up to you, as implementer of an API, to decide how to use the capabilities. So each party (or party role) has its own contact medium, but it might be useful to have contact information at the level of the appointment itself.
Hope it helps
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Jonathan Goldberg
Amdocs Management Limited
Any opinions and statements made by me on this forum are purely personal, and do not necessarily reflect the position of the TM Forum or my employer.
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