HTTP1.1 vs HTTP2 | Difference between HTTP1.1 and HTTP2
This page compares HTTP1.1 vs HTTP2 and mentions difference between HTTP1.1 and HTTP2 protocol types.
HTTP1.1 protocol
It was published in 1997 for providing improvement over HTTP protocol. It is World Wide Web (WWW) protocol which runs on top of TCP/IP protocol stack. It uses text based commands for communication between client and web server. It offers faster web page loading compare to HTTP and reduces web traffic.
The features of HTTP/1.1 protocol are as follows.
• Single request/response at a time, Browsers use multiple connections to achieve
concurrent requests and responses
• Requests and responses are text based
• Required host header
• Condition caching headers
• Digest authentication and proxy authentication
• Chunked transfer encoding
• Connection header
• Enhanced compression support
HTTP2 protocol

It was published in Feb. 2015 for providing many improvements over HTTP/1.1 protocol.
It uses binary data for communication between client and web server.
It offers faster web page loading compare to HTTP/1.1 protocol.
Figure depicts major difference between HTTP1.1 and HTTP2 protocols.
• Multiplexing : Multiple requests and responses are sent at a time over single connection
• Server push : Server pushes resources to client which reduces number of round trips and improves performance to
load web page faster.
• Supports header compression which reduces amount of data over connection.
• Supports prioritization of requests and responses which allows resources to be loaded faster.
• Supports binary format which is more efficient than text based format used in HTTP1.1
• Supports flow control mechanism to ensure client does not receive more data than its capacity and
server does not send more than client's capacity.
• Supports HTTPS encryption protocol
Difference between HTTP1.1 and HTTP2
Following is the tabular difference between HTTP1.1 and HTTP2.
Feature | HTTP1.1 | HTTP2 |
---|---|---|
Multiplexing | Not supported | Supported, Multiple requests/responses are sent over single connection. |
Server Push | Not supported | Supported, Server pushes resources to the client which enables faster web page loading. |
Header compression | Not supported | Supported using HPACK |
Prioritization | Not supported | Supported, offers better user experience |
Protocol data type | Text | Binary |
Encryption | Supports SSL/TLS | Supports HTTPS |
Flow control | Not supported | Supported |
Reference RFCs | It uses RFC 2616 | It uses RFC 7540 |
➨Also refer advantages and disadvantages of HTTP protocol >> and HTTP2 protocol >> for more information.