ASP.NET Core offers first-class gRPC support, making it a strong option for high-performance distributed systems and microservices.
gRPC’s throughput largely comes from HTTP/2 plus Protocol Buffers. HTTP/2 brings multiplexing, header compression, and server push, reducing latency and bandwidth. Protocol Buffers is a compact binary format that’s smaller and faster than JSON or XML.
The two key ingredients are:
This raises a practical question: if a REST API also uses HTTP/2 and a compact serializer, can it close the gap?
In ASP.NET Core, you can support both JSON and Protocol Buffers (and others) simultaneously to suit different clients.
See the docs on custom formatters. This lets you add formats like XML, Protocol Buffers, and MessagePack without invasive changes.
You can also configure Kestrel to select specific HTTP protocol versions. See Configure HTTP protocols.
If performance is the only goal, gRPC isn’t the only answer—it’s one implementation choice with its own learning curve and trade-offs. A REST API using HTTP/2 and an efficient serializer can also perform very well.
gRPC’s biggest convenience is robust client support across languages, which simplifies cross-language calls.