HPACK
E40363
HPACK is the dedicated header compression format used by HTTP/2 to efficiently encode and transmit HTTP header fields while maintaining security and performance.
Observed surface forms (4)
| Surface form | As subject | As object |
|---|---|---|
| HPACK: Header Compression for HTTP/2 | 0 | 2 |
| HTTP/2 HPACK header compression specification | 0 | 1 |
| IANA HPACK static table registry | 0 | 1 |
| Internet Standard for HTTP/2 header compression | 0 | 1 |
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
HTTP/2 component
→
header compression format → |
| appliesTo |
HTTP header field names
→
HTTP header field values → |
| compressionScope |
HTTP request headers
→
HTTP response headers → |
| defines |
Huffman code table for header field values
→
binary encoding for header fields → static header field table entries → |
| designedFor |
efficient encoding of HTTP header fields
→
improving HTTP/2 performance → mitigating security risks of header compression → reduction of HTTP header size → |
| encodingType | binary → |
| fullName |
HPACK
self-linksurface differs
→
surface form: "HPACK: Header Compression for HTTP/2"
|
| hasGoal |
compression efficiency
→
deterministic memory use → low CPU overhead → protection against compression side‑channel attacks → |
| hasLimit | configurable maximum dynamic table size → |
| influencedBy | SPDY header compression → |
| influences | QPACK header compression for HTTP/3 → |
| publicationYear | 2015 → |
| publishedBy |
Internet Engineering Task Force
→
surface form: "IETF"
|
| relatedTo |
HTTP/2
→
QPACK → |
| replaces | generic compression of HTTP headers used in HTTP/1.x → |
| securityProperty |
allows limiting dynamic table size per endpoint
→
avoids use of general‑purpose stream compression over TLS for headers → reduces risk of CRIME‑like attacks on HTTP headers → |
| standardizedIn | RFC 7541 → |
| status |
HPACK
self-linksurface differs
→
surface form: "Internet Standard for HTTP/2 header compression"
|
| supportsOperation |
header table eviction
→
header table insertion → header table resizing → indexed header field representation → literal header field never indexed → literal header field representation → literal header field with indexing → literal header field without indexing → |
| usedByProtocol | HTTP/2 → |
| usesDataStructure |
dynamic table
→
static table → |
| usesTechnique |
dynamic Huffman coding
→
header table indexing → indexed representation of header fields → static Huffman coding → |
| workingGroup |
HTTP Working Group
→
surface form: "IETF HTTPbis Working Group"
|
Referenced by (8)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form: "HPACK: Header Compression for HTTP/2"
this entity surface form: "HTTP/2 HPACK header compression specification"
this entity surface form: "Internet Standard for HTTP/2 header compression"