"description": "The version of the VoIP specification this message adheres to. This specification is version 1. This field is a string such that experimental implementations can use non-integer versions. This field was an integer in the previous spec version and implementations must accept an integer 0"
"description": "This identifies the party that sent this event. A client may choose to re-use the device ID from end-to-end cryptography for the value of this field. "