gRPC

gRPC is a relatively new, kind of complicated API system that's better for two way streaming and other data-heavy uses. Unfortunately, many features are only available in browsers that support HTTP/2.0 A lot of its efficiency may be due to:

• using google ProtocolBuffers instead of JSON or XML as the data encoding (actually, sending JSON compressed is probably just as efficient, but of course requires an encode/decode stage)
• using features that gang up multiple data blocks efficiently. You can also full duplex transmissions to the server.

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