May 20, 2023

HTTP/2 is a protocol for transporting web content between servers and clients. It is the successor of the HTTP/1.1 protocol, which has been in use since 1999. HTTP/2 was designed to address the limitations of its predecessor and to improve the performance and security of web communication.

Purpose and Usage

HTTP/2 was designed to improve the performance of web communication by reducing latency and improving the speed at which pages are loaded. It does this by introducing several new features that were not present in HTTP/1.1.


One of the key features of HTTP/2 is multiplexing. This allows multiple requests and responses to be sent over a single connection. In HTTP/1.1, a new connection had to be established for each request/response pair, which led to a lot of overhead and increased latency. With HTTP/2, multiple requests can be sent over a single connection, which reduces the amount of overhead and improves the speed at which pages are loaded.

Server Push

Another feature of HTTP/2 is server push. This allows the server to push content to the client without the client having to request it. For example, if a page requires several resources to load (such as CSS, JavaScript, and images), the server can push those resources to the client before the client requests them. This can lead to significant performance improvements, as the client does not have to wait for the server to send the resources.

Header Compression

HTTP/2 also introduces header compression. In HTTP/1.1, headers were sent in plain text, which added a lot of overhead to each request/response pair. With HTTP/2, headers are compressed, which reduces the amount of overhead and improves the speed at which pages are loaded.

Binary Protocol

Finally, HTTP/2 uses a binary protocol instead of a text-based protocol. This allows for more efficient parsing and reduces the amount of data that needs to be sent over the network.


To use HTTP/2, both the server and the client must support the protocol. Most modern web servers and browsers support HTTP/2, including Apache, Nginx, Chrome, Firefox, and Edge.

To enable HTTP/2 on a server, the server must have a valid SSL/TLS certificate installed. This is because HTTP/2 requires that all communication be encrypted. Once the certificate is installed, the server can be configured to use HTTP/2 instead of HTTP/1.1.

To use HTTP/2 on the client side, the browser must support the protocol. Most modern browsers support HTTP/2, including Chrome, Firefox, Safari, and Edge. If the server supports HTTP/2 and the browser supports HTTP/2, the browser will automatically use HTTP/2 to communicate with the server.


As mentioned earlier, HTTP/2 requires that all communication be encrypted. This is enforced through the use of SSL/TLS certificates. By encrypting all communication, HTTP/2 provides an additional layer of security, which helps to prevent eavesdropping and other types of attacks.

However, HTTP/2 is not a substitute for other security measures, such as strong passwords, firewalls, and content security policies. It is important to use HTTP/2 in conjunction with other security measures to ensure the safety and privacy of web communication.

Comparison with HTTP/1.1

HTTP/2 is a significant improvement over HTTP/1.1. It provides better performance, improved security, and more efficient communication between servers and clients. The following table summarizes some of the key differences between HTTP/1.1 and HTTP/2:

Server PushNoYes
Header CompressionNoYes
Binary ProtocolNoYes