What is GRPC (Google Remote Procedure Call)?

Google Remote Procedure Call is a framework that allows services to communicate with each other efficiently and quickly. By using GRPC, developers can build distributed applications more easily.

What is GRPC?

GRPC is an RPC (Remote Procedure Call) protocol based on HTTP/2, allowing clients and servers to communicate through methods defined in protobuffers.

GRPC is an open source framework designed to make building microservices easier and more efficient. With GRPC, developers can call remote methods on other servers as if they were running on the same machine. This helps optimize the application development process, especially in cross-platform environments.

Origin of GRPC

Before 2000, Remote Procedure Call (RPC) was the go-to method for service requests. RPC calls were efficient but complex. They were tightly coupled to specific implementations and could be unsafe, as they could expose too much of their internal details to the outside world.

Representational State Transfer (REST) ​​was designed to solve these problems. It provides a set of common methods for client-server communication. GET and POST will be familiar to most web developers. REST is easy to work with but not efficient. There are limitations to its request-response model and its data needs to be serialized for transmission, adding performance overhead.

To improve this situation, Google developed gRPC. GRPC was built on top of SPDY, an HTTP-compatible protocol developed by Google. However, after SPDY was standardized as HTTP/2, gRPC switched to using HTTP/2 as its primary transport protocol.

In August 2016, gRPC was officially released to the open source community.

GRPC uses Protocol Buffers (protobuf) as its interface definition language (IDL) and serialization engine. This enables GRPC to achieve higher performance and better scalability than previous technologies.

Why use GRPC?

GRPC brings many benefits to today's application development. Here are some of the prominent reasons why programmers often choose GRPC for their projects.

For performance

Performance is an extremely important factor in developing distributed applications. GRPC provides fast and efficient communication thanks to the use of HTTP/2.

Each GRPC connection can contain multiple requests and responses, which reduces overhead and saves bandwidth. Additionally, GRPC uses a binary protocol for data transmission, which increases speed compared to text protocols such as JSON.

For growth rate

By using .proto files to define methods and data types, programmers can easily automatically generate code for many different programming languages.

Other possibilities

GRPC does more than just provide an efficient communication protocol. It also supports a variety of other features such as authentication, error checking, and session management. These features help reduce the workload for programmers and improve application reliability.

Benefits of GRPC

GRPC offers many benefits to application development projects. Here are some of the prominent benefits that GRPC offers.

Speed ​​and efficiency

One of the biggest benefits of GRPC is its superior data transfer speed. Thanks to the use of HTTP/2 and the binary protocol, GRPC can handle millions of requests per second without slowing down.

Two-way streaming

GRPC allows clients and servers to communicate continuously without having to create a new connection for each request. This is useful in applications that need to be constantly updated, such as chat applications or online games.

HTTP/2

The use of HTTP/2 is one of the key factors that helps GRPC achieve high performance. HTTP/2 allows multiple requests to be transmitted concurrently over the same connection, which helps reduce latency and increase scalability for applications.

Additionally, HTTP/2 supports multiplexing, allowing multiple requests and responses to be sent simultaneously without having to wait for each one to complete. 

How gRPC works

To better understand GRPC, we need to learn about how it works. GRPC is based on the client-server model, in which the client sends requests to the server and receives responses.

Request submission process

When a client wants to call a method on the server, it sends a request containing information about the method and the required parameters. GRPC then encodes this request using protobuf and transmits it over HTTP/2 to the server.

The server will receive the request, decode it and execute the corresponding method. Once done, the server will send a response back to the client following the same process.

Handling feedback

The response from the server will also be encoded using protobuf and sent over an HTTP/2 connection. The client will receive the response, decode it and process it the way it was programmed.

What's special is that GRPC supports streaming for both requests and responses, allowing clients and servers to continuously send and receive data without having to wait for each other.

Connect and communicate

GRPC maintains a persistent connection between the client and server, saving resources compared to creating a new connection each time communication occurs. This connection can last for the entire lifetime of the application, minimizing latency and optimizing transmission speed.

Strengths and weaknesses of gRPC

GRPC offers many benefits but also has some weaknesses that programmers need to consider.

Strengths

One of GRPC's biggest strengths is its high performance. The use of HTTP/2 and binary protocol increases data transfer speed and reduces bandwidth requirements.

GRPC also supports many different programming languages ​​and provides automatic code generation tools, helping to speed up the development process.

Weaknesses

Despite its many advantages, GRPC also has some limitations. One of them is that it requires knowledge of protobuf and how to use the accompanying tools, making it difficult for novice programmers.

GRPC is not well suited for applications that need to communicate over the public internet, where firewalls may interfere with HTTP/2 connections.

Language Agnostic

One of the reasons why GRPC is so popular is its compatibility with many different programming languages.

Code Generation

GRPC allows automatic generation of code for different languages ​​from .proto definition files. This not only saves time but also ensures uniformity in communication between services.

Programmers simply define methods and data types in the .proto file, and GRPC automatically generates code for the languages ​​they need.

Security

GRPC also provides strong security features. It supports TLS (Transport Layer Security) to encrypt data during transmission, helping to protect sensitive information between client and server.

GRPC also supports user authentication through tokens or certificates, helping to ensure that only valid users have access to the service.

formal specification

GRPC has an official specification that anyone can refer to. This makes it easier to develop and implement GRPC, and creates a strong community around it.

With clear specifications, developers can easily follow and update new features. They can also contribute to the project and share their experiences with the community.

Deadline

GRPC allows developers to set deadlines for requests, helping to control response times and handle errors effectively. If a request is not completed within the specified time, GRPC automatically aborts the request, saving resources and optimizing application performance.

Conclude

GRPC (Google Remote Procedure Call) is a powerful and flexible technology for developing distributed applications. With many outstanding features, GRPC has scored points in the hearts of the programming community.

However, like any technology, GRPC has its own limitations. Therefore, before deciding to use GRPC for their projects, programmers need to carefully consider the relevant factors to ensure that they choose the most suitable solution for their needs.

Kareem Winters

Update 19 April 2025