Multiple phones in each room
When connecting MEWS with a PBX, the phone in the physical room is defined as a Space, or resource, in MEWS.
The name of the Space is the actual phone extension number, often the same as the room number.
As only one resource can be associated with a Reservation, we run into a problem when a room/suite is equipped with more than one phone, not uncommon in "high class" hotels. Each of these phones (=MEWS resources) needs somehow to be associated with the same Reservation.
Bjarne Ingelsson commented
An option could be to add customer defined key-value fields to the resource object, which the application then could read.
I.e ["Phones"] => ["11101,12101"] where the key is customer defined and the value could hold whatever data understandable by the application, in this example a list of phone-numbers.