The SyncML Initiative got consolidated into the OMA umbrella as the scope and use of the specification was expanded to include many more devices and support global operation.
Technically, the OMA DM protocol uses XML for data exchange, more specifically the sub-set defined by SyncML.
The server and client are both stateful, meaning a specific sequence of messages are to be exchanged only after authentication is completed to perform any task.
Once the communication is established between the server and client, a sequence of messages might be exchanged to complete a given device management task.
Several parameters relating to the communication such as the maximum message size can be negotiated between the server and client during the initiation of a session.