The Packet Header contains a single key called "fields".

JSON key: fields

This defines the fields contained in the common message header of the protocol you want to decode.

"PacketHeader" : {
"fields": [
{ "name": "Timestamp", "type": "INT64_LE" },
{ "name": "StreamID", "type": "INT8" },
{ "name": "MsgBlockCount", "type": "INT8", "flags": ["msg_count"] }
]

The additional keys provided in the “fields“ key are described in section MessageHeader.