HPACK is a compression format for data fields of the HTTP protocol standardized by the Internet Engineering Task Force (IETF) in conjunction withHTTP/2
. Generally, the data fields of the HTTP header are uncompressed. However, since web page content often consists of dozens or hundreds of requests, an unnecessary amount of bandwidth is required for redundant header fields, which ultimately increases latency. HPACK addresses header field redundancy and eliminates redundant header fields, as well as security-related vulnerabilities.