Proto2 and proto3 are wire compatible. The same construct in proto2 and
proto3 will have the same binary representation. If your proto only uses
features available in both proto2 and proto3, systems built with proto2
should be able to communicate with systems built with proto3 without any
problem
Hi,
I haven't been able to find any documentation that explicitly states
whether the wire (binary) format of Protobuf v2 messages are compatible
with protobuf messages generated with v3 (using `syntax=proto2`). The only
documentation seems to mention API differences between the two library
