What transport protocol does gRPC use? What is the difference between HTTP/2 and HTTP/1.1?

gRPC uses the HTTP/2 transport protocol for data transfer.

Main differences between HTTP/2 and HTTP/1.1:

• Multiplexing: HTTP/2 allows sending multiple requests and receiving responses simultaneously over a single TCP connection, significantly reducing latency. In HTTP/1.1, requests are processed sequentially or with limited parallelism.

• Binary protocol: HTTP/2 transmits data in a binary format, unlike HTTP/1.1 which uses text. This simplifies parsing and increases efficiency.

• Header compression: HTTP/2 uses HPACK to compress headers, reducing the amount of data transmitted.

• Stream prioritization: HTTP/2 allows clients to specify request priorities, helping the server allocate resources optimally.

• Server push support: HTTP/2 can send resources to the client without explicit requests, speeding up loading.

Example of initializing a gRPC server in Go (uses HTTP/2 under the hood):

import (
    "google.golang.org/grpc"
    "net"
)

func main() {
    lis, err := net.Listen("tcp", ":50051")
    if err != nil {
        panic(err)
    }
    grpcServer := grpc.NewServer()
    // Register services...
    grpcServer.Serve(lis)
}