What the sequence numbers in the proto file represent
What makes Protobuf different from any other communication protocols or data storage formats is that each field, in its objects, has an equality sign (==) at the end, followed by a unique integer number. The equality sign followed by a numeric value is how you would normally assign a numeric value to a variable, but in Protobuf, it represents a unique sequence number of the field.
The reason these sequence numbers exist is that they are the only field identifiers that are used when the message is being transferred between the client and the server. The Protobuf messaging format has been designed to be as efficient as possible. Using arbitrary byte arrays to represent human-readable field names isn't very efficient. Instead, using numeric identifiers is the simplest way of both keeping track of each unique field and keeping the data payload size as small as possible.
Another feature that makes Protobuf so efficient is...