HPACK - Header Compression for HTTP/2.0
draft-ietf-httpbis-header-compression-04
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| Authors | Roberto Peon , Herve Ruellan | ||
| Last updated | 2013-10-21 | ||
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draft-ietf-httpbis-header-compression-04
HTTPbis Working Group R. Peon
Internet-Draft Google, Inc
Intended status: Informational H. Ruellan
Expires: April 24, 2014 Canon CRF
October 21, 2013
HPACK - Header Compression for HTTP/2.0
draft-ietf-httpbis-header-compression-04
Abstract
This document describes HPACK, a format adapted to efficiently
represent HTTP header fields in the context of HTTP/2.0.
Editorial Note (To be removed by RFC Editor)
Discussion of this draft takes place on the HTTPBIS working group
mailing list (ietf-http-wg@w3.org), which is archived at
<http://lists.w3.org/Archives/Public/ietf-http-wg/>.
Working Group information and related documents can be found at
<http://tools.ietf.org/wg/httpbis/> (Wiki) and
<https://github.com/http2/http2-spec> (source code and issues
tracker).
The changes in this draft are summarized in Appendix A.1.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 24, 2014.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
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document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Outline . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Header Field Encoding . . . . . . . . . . . . . . . . . . . . 5
3.1. Encoding Concepts . . . . . . . . . . . . . . . . . . . . 5
3.1.1. Encoding Context . . . . . . . . . . . . . . . . . . . 5
3.1.2. Header Table . . . . . . . . . . . . . . . . . . . . . 6
3.1.3. Reference Set . . . . . . . . . . . . . . . . . . . . 6
3.1.4. Header Field Representation . . . . . . . . . . . . . 7
3.1.5. Header Field Emission . . . . . . . . . . . . . . . . 8
3.2. Header Block Decoding . . . . . . . . . . . . . . . . . . 8
3.2.1. Header Field Representation Processing . . . . . . . . 8
3.2.2. Reference Set Emission . . . . . . . . . . . . . . . . 9
3.2.3. Header Set Completion . . . . . . . . . . . . . . . . 9
3.3. Header Table Management . . . . . . . . . . . . . . . . . 9
3.3.1. Maximum Table Size . . . . . . . . . . . . . . . . . . 9
3.3.2. Entry Eviction When Header Table Size Changes . . . . 10
3.3.3. Entry Eviction when Adding New Entries . . . . . . . . 10
4. Detailed Format . . . . . . . . . . . . . . . . . . . . . . . 10
4.1. Low-level representations . . . . . . . . . . . . . . . . 10
4.1.1. Integer representation . . . . . . . . . . . . . . . . 11
4.1.2. String Literal Representation . . . . . . . . . . . . 13
4.2. Indexed Header Field Representation . . . . . . . . . . . 14
4.3. Literal Header Field Representation . . . . . . . . . . . 15
4.3.1. Literal Header Field without Indexing . . . . . . . . 15
4.3.2. Literal Header Field with Incremental Indexing . . . . 16
5. Security Considerations . . . . . . . . . . . . . . . . . . . 17
6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.1. Normative References . . . . . . . . . . . . . . . . . . . 18
6.2. Informative References . . . . . . . . . . . . . . . . . . 18
Appendix A. Change Log (to be removed by RFC Editor before
publication . . . . . . . . . . . . . . . . . . . . . 19
A.1. Since draft-ietf-httpbis-header-compression-03 . . . . . . 19
A.2. Since draft-ietf-httpbis-header-compression-02 . . . . . . 19
A.3. Since draft-ietf-httpbis-header-compression-01 . . . . . . 19
A.4. Since draft-ietf-httpbis-header-compression-01 . . . . . . 19
Appendix B. Static Table . . . . . . . . . . . . . . . . . . . . 20
Appendix C. Huffman Codes For Requests . . . . . . . . . . . . . 22
Appendix D. Huffman Codes for Responses . . . . . . . . . . . . . 28
Appendix E. Examples . . . . . . . . . . . . . . . . . . . . . . 33
E.1. Request Decoding Example With Huffman . . . . . . . . . . 33
E.2. Request Decoding Example Without Huffman . . . . . . . . . 38
E.3. Response Decoding Example With Huffman . . . . . . . . . . 43
E.4. Response Decoding Example Without Huffman . . . . . . . . 51
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1. Introduction
This document describes HPACK, a format adapted to efficiently
represent HTTP header fields in the context of HTTP/2.0 (see
[HTTP2]).
2. Overview
In HTTP/1.X (see [HTTP-p1]), header fields are sent without any form
of compression. As web pages have grown to include dozens to
hundreds of requests, the redundant header fields in these requests
now pose a problem of measurable latency and unnecessary bandwidth
(see [PERF1] and [PERF2]).
SPDY [SPDY] initially addressed this redundancy by compressing header
fields with Deflate, which proved very effective at eliminating the
redundant header fields. However, that aproach exposed a security
risk as demonstrated by the CRIME [CRIME].
In this document, we propose a new compressor for header fields which
eliminates redundant header fields, is not vulnerable to CRIME style
attacks, and which also has a bounded memory cost for use in
constrained environments.
2.1. Outline
The HTTP header field encoding described in this document is based on
a header table that map (name, value) pairs to index values. Header
tables are incrementally updated during the HTTP/2.0 session.
The encoder is responsible for deciding which header fields to insert
as new entries in the header table. The decoder then does exactly
what the encoder prescribes, ending in a state that exactly matches
the encoder's state. This enables decoders to remain simple and
understand a wide variety of encoders.
As two consecutive sets of header fields often have header fields in
common, each set of header fields is coded as a difference from the
previous set of header fields. The goal is to only encode the
changes (header fields present in one of the set and not in the
other) between the two sets of header fields.
Examples illustrating the use of these different mechanisms to
represent header fields are available in Appendix E.
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3. Header Field Encoding
3.1. Encoding Concepts
The encoding and decoding of header fields relies on some components
and concepts:
Header Field: A key, value pair. HPACK allows a header field value
to be either a value as specified by HTTP/1.X (see [HTTP-p1]), or
a NULL-separated ordered list of HTTP/1.X values.
Header Table: The header table (see Section 3.1.2) is a component
used to associate stored header fields to index values. The data
stored in this table is in first-in, first-out order.
Static Table: The static table (see Appendix B) is a component used
to associate static header fields to index values. This data is
ordered, read-only, always accessible, and may be shared amongst
all encoding contexts.
Reference Set: The reference set (see Section 3.1.3) is a component
containing an unordered set of references to entries in the header
table or static table. This is used for the differential encoding
of a new header set.
Header Set: A header set is a potentially ordered group of header
fields that are encoded jointly. A complete set of key-value
pairs contained in a HTTP request or response is a header set.
Header Field Representation: A header field can be represented in
encoded form either as a literal or as an index (see
Section 3.1.4).
Header Block: The entire set of encoded header field representations
which, when decoded, yield a complete header set.
Header Field Emission: When decoding a set of header field
representations, some operations emit a header field (see
Section 3.1.5). Emitted headers can be safely passed to the upper
processing layers as part of the current Header Set.
3.1.1. Encoding Context
The set of mutable structures used within an encoding context include
a header table and a reference set. Everything else is either
immutable or conceptual.
Using HTTP, messages are exchanged between a client and a server in
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both direction. To keep the encoding of header fields in each
direction independent from the other direction, there is one encoding
context for each direction.
The header fields contained in a PUSH_PROMISE frame sent by a server
to a client are encoded within the same context as the header fields
contained in the HEADERS frame corresponding to a response sent from
the server to the client.
3.1.2. Header Table
A header table consists of a list of header fields maintained in
first-in, first-out order. The first and newest entry in a header
table is always at index 0, and the oldest entry of a header table is
at the index len(header table)-1.
The header table is initially empty.
There is typically no need for the header table to contain duplicate
entries. However, duplicate entries MUST NOT be treated as an error
by a decoder.
The encoder decides how to update the header table and as such can
control how much memory is used by the header table. To limit the
memory requirements on the decoder side, the header table size is
strictly bounded (see Section 3.3.1).
The header table is updated during the processing of a set of header
field representations (see header field representation processing
(Section 3.2.1).
3.1.3. Reference Set
A reference set is an unordered set of references to entries either
within the header table or the static table.
The reference set is initially empty.
The reference set is updated during the processing of a set of header
field representations (see header field representation processing
(Section 3.2.1).
The reference set enables differential encoding, whereby only
differences between the previous header set and the current header
set need to be encoded.
When an entry is evicted from the header table, if it was referenced
from the reference set, its reference is removed from the reference
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set.
3.1.4. Header Field Representation
An encoded header field can be represented either as a literal or as
an index.
Literal Representation: A literal representation defines a new
header field. The header field name is represented either
literally or as a reference to an entry of the header table. The
header field value is represented literally.
Two different literal representations are provided:
* A literal representation that does not add the header field to
the header table (see Section 4.3.1).
* A literal representation that adds the header field as a new
entry at the beginning of the header table (see Section 4.3.2).
Indexed Representation: The indexed representation defines a header
field as a reference to an entry in either the header table or the
static table(see Section 4.2).
<---------- Index Address Space ---------->
<-- Header Table --> <-- Static Table -->
+---+-----------+---+ +---+-----------+---+
| 0 | ... | k | |k+1| ... | n |
+---+-----------+---+ +---+-----------+---+
^ |
| V
Insertion Point Drop Point
Index Address Space
Indices between 0 and len(header table)-1, inclusive, refer to
elements in the header table, with index 0 referring to the
beginning of the table.
Indices between len(header table) and len(header table)+
len(static table)-1, inclusive, refer to elements in the static
table, where the index len(header table) refers to the first
entry in the static table.
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Any other indices MUST be treated as erroneous, and the
compression context considered corrupt and unusable.
3.1.5. Header Field Emission
The emission of a header field is the process of passing that header
field to the application, so that the application can process and
react to header field data.
By emitting header fields instead of emitting header sets, the
decoder can be implemented in a streaming way, and as such must only
keep in memory the header table and the reference set. This bounds
the amount of memory used by the decoder, even in presence of a very
large set of header fields. The management of memory for handling
very large sets of header fields can therefore be deferred to the
application.
When a header field is a NULL-separated list of values, each value
within the list MAY be emitted separately, with the same header field
name, and the order of emission MUST be the order of appearance in
the list.
3.2. Header Block Decoding
The processing of a header block to obtain a header set is defined in
this section. To ensure that the decoding will successfully produce
a header set, a decoder MUST obey the following rules.
3.2.1. Header Field Representation Processing
All the header field representations contained in a header block are
processed in the order in which they are presented, as specified
below.
An _indexed representation_ corresponding to an entry _present_ in
the reference set entails the following actions:
o The reference to the entry is removed from the reference set.
An _indexed representation_ corresponding to an entry _not present_
in the reference set entails the following actions:
o If referencing an element of the static table:
* The header field corresponding to the referenced entry is
emitted.
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* The referenced static entry is added to the header table.
* If the new entry fits within the header table, a reference to
the header table entry is added to the reference set.
o If referencing an element of the header table:
* The header field corresponding to the referenced entry is
emitted.
* The referenced header table entry is added to the header table.
A _literal representation_ that is _not added_ to the header table
entails the following action:
o The header field is emitted.
A _literal representation_ that is _added_ to the header table
entails the following actions:
o The header field is inserted at the beginning of the header table.
o A reference to the new entry is added to the reference set.
o The header field is emitted.
3.2.2. Reference Set Emission
Once all the representations contained in a header block have been
processed, the header fields referenced in the reference set which
have not previously been emitted during this processing are emitted.
3.2.3. Header Set Completion
Once all of the header field representations have been processed, and
the remaining items in the reference set have been emitted, the
header set is complete.
3.3. Header Table Management
3.3.1. Maximum Table Size
To limit the memory requirements on the decoder side, the size of the
the header table is bounded. The size of the header table MUST stay
lower than or equal to the value of the HTTP/2.0 setting
SETTINGS_HEADER_TABLE_SIZE (see [HTTP2]).
The size of the the header table is the sum of the size of its
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entries.
The size of an entry is the sum of its name's length in bytes (as
defined in Section 4.1.2), of its value's length in bytes
(Section 4.1.2) and of 32 bytes.
The lengths are measured on the non-encoded entry name and entry
value (for the case when a Huffman encoding is used to transmit
string values).
The 32 bytes are an accounting for the entry structure overhead. For
example, an entry structure using two 64-bits pointers to reference
the name and the value and the entry, and two 64-bits integer for
counting the number of references to these name and value would use
32 bytes.
3.3.2. Entry Eviction When Header Table Size Changes
Whenever an entry is evicted from the header table, any reference to
that entry contained by the reference set is removed.
Whenever SETTINGS_HEADER_TABLE_SIZE is made smaller, entries are
evicted from the end of the header table until the size of the header
table is less than or equal to SETTINGS_HEADER_TABLE_SIZE.
The eviction of an entry from the header table causes the index of
the entries in the static table to be reduced by one.
3.3.3. Entry Eviction when Adding New Entries
Whenever a new entry is to be added to the table, any name referenced
by the representation is cached, and then entries are evicted from
the end of the header table until the size of the header table is
less than or equal to SETTINGS_HEADER_TABLE_SIZE - new entry size, or
until the table is empty.
If the size of the new entry is less than or equal to
SETTINGS_HEADER_TABLE_SIZE, that entry is added to the table. It is
not an error to attempt to add an entry that is larger than
SETTINGS_HEADER_TABLE_SIZE.
4. Detailed Format
4.1. Low-level representations
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4.1.1. Integer representation
Integers are used to represent name indexes, pair indexes or string
lengths. To allow for optimized processing, an integer
representation always finishes at the end of a byte.
An integer is represented in two parts: a prefix that fills the
current byte and an optional list of bytes that are used if the
integer value does not fit within the prefix. The number of bits of
the prefix (called N) is a parameter of the integer representation.
The N-bit prefix allows filling the current byte. If the value is
small enough (strictly less than 2^N-1), it is encoded within the
N-bit prefix. Otherwise all the bits of the prefix are set to 1 and
the value is encoded using an unsigned variable length integer [1]
representation. N is always between 1 and 8 bits. An integer
starting at a byte-boundary will have an 8-bit prefix.
The algorithm to represent an integer I is as follows:
If I < 2^N - 1, encode I on N bits
Else
encode 2^N - 1 on N bits
I = I - (2^N - 1)
While I >= 128
Encode (I % 128 + 128) on 8 bits
I = I / 128
encode (I) on 8 bits
This integer representation allows for values of indefinite size. It
is also possible for an encoder to send a large number of zero
values, which can waste bytes and could be used to overflow integer
values. Excessively large integer encodings - in value or octet
length - MUST be treated as a decoding error. Different limits can
be set for each of the different uses of integers, based on
implementation constraints.
4.1.1.1. Example 1: Encoding 10 using a 5-bit prefix
The value 10 is to be encoded with a 5-bit prefix.
o 10 is less than 31 (= 2^5 - 1) and is represented using the 5-bit
prefix.
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| X | X | X | 0 | 1 | 0 | 1 | 0 | 10 stored on 5 bits
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+---+---+---+---+---+---+---+---+
4.1.1.2. Example 2: Encoding 1337 using a 5-bit prefix
The value I=1337 is to be encoded with a 5-bit prefix.
1337 is greater than 31 (= 2^5 - 1).
The 5-bit prefix is filled with its max value (31).
I = 1337 - (2^5 - 1) = 1306.
I (1306) is greater than or equal to 128, the while loop body
executes:
I % 128 == 26
26 + 128 == 154
154 is encoded in 8 bits as: 10011010
I is set to 10 (1306 / 128 == 10)
I is no longer greater than or equal to 128, the while loop
terminates.
I, now 10, is encoded on 8 bits as: 00001010
The process ends.
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| X | X | X | 1 | 1 | 1 | 1 | 1 | Prefix = 31, I = 1306
| 1 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1306>=128, encode(154), I=1306/128
| 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 10<128, encode(10), done
+---+---+---+---+---+---+---+---+
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4.1.2. String Literal Representation
Header field names and header field values are encoded as sequences
of bytes. A header field name or a header field value is encoded in
three parts:
1. One bit, H, indicating whether or not the bytes are huffman
encoded.
2. The number of bytes required to hold the result of the next step,
represented as a variable-length-quantity (Section 4.1.1),
starting with a 7-bit prefix immediately following the first bit.
3. The encoded data of the string:
1. If H is true, then the the encoded string data is the bitwise
concatenation of the canonical [CANON]huffman code [HUFF]
corresponding to each character of the data, followed by
between 0-7 bits of padding.
2. If H is false, then the encoded string is the bytes of the
field value without modification.
Padding is necessary when doing huffman encoding to ensure that the
remaining bits between the actual end of the data and the next byte
boundary are not misinterpreted as part of the input data.
When padding for huffman encoding, use the bits from the EOS (end-of-
string) entry in the Huffman table, starting with the MSB. This
entry is guaranteed to be at least 8 bits long.
String literals sent in the client to server direction which use
huffman encoding are encoded with the codes within the request
huffman code table (Appendix C) (see Request Decoding With Huffman
Example (Appendix E.3)).
String literals sent in the server to client direction which use
huffman encoding are encoded with the codes within the response
huffman code table (Appendix D) (see Response Decoding With Huffman
Example (Appendix E.3)).
The EOS symbol is represented with value 256, and is used solely to
signal the end of the huffman-encoded key data or the end of the
huffman-encoded value data. Given that only between 0-7 bits of the
EOS symbol is included in any huffman-encoded string, and given that
the EOS symbol is at least 8 bits long, it is expected that it should
never be successfully decoded.
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0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 1 | Value Length Prefix (7) |
+---+---+---+---+---+---+---+---+
| Value Length (0-N bytes) |
+---+---+---+---+---+---+---+---+
...
+---+---+---+---+---+---+---+---+
| Huffman Encoded Data |Padding|
+---+---+---+---+---+---+---+---+
String Literal With Huffman Encoding
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 0 | Value Length Prefix (7) |
+---+---+---+---+---+---+---+---+
| Value Length (0-N bytes) |
+---+---+---+---+---+---+---+---+
...
+---+---+---+---+---+---+---+---+
| Field Bytes Without Encoding |
+---+---+---+---+---+---+---+---+
String Literal Without Huffman Encoding
4.2. Indexed Header Field Representation
An indexed header field representation either identifies an entry in
the header table or static table. The specified entry is emitted and
a reference to that entry is added to the reference set if it is not
currently in the reference set. If it is present in the reference
set then the reference is removed and the entry is not emitted.
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 1 | Index (7+) |
+---+---------------------------+
Indexed Header Field
This representation starts with the '1' 1-bit pattern, followed by
the index of the matching pair, represented as an integer with a
7-bit prefix.
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4.3. Literal Header Field Representation
Literal header field representations contain a literal header field
value. Header field names are either provided as a literal or by
reference to an existing header table or static table entry.
Literal representations all result in the emission of a header field
when decoded.
4.3.1. Literal Header Field without Indexing
A literal header field without indexing causes the emission of a
header field without altering the header table.
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 0 | 1 | Index (6+) |
+---+---+---+-------------------+
| Value Length (8+) |
+-------------------------------+
| Value String (Length octets) |
+-------------------------------+
Literal Header Field without Indexing - Indexed Name
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 0 | 1 | 0 |
+---+---+---+-------------------+
| Name Length (8+) |
+-------------------------------+
| Name String (Length octets) |
+-------------------------------+
| Value Length (8+) |
+-------------------------------+
| Value String (Length octets) |
+-------------------------------+
Literal Header Field without Indexing - New Name
This representation starts with the '01' 2-bit pattern.
If the header field name matches the header field name of a (name,
value) pair stored in the Header Table or Static Table, the index of
that entry, increased by one (index + 1), is represented as an
integer with a 6-bit prefix. Note that if the index is strictly
below 63, only one byte is used for this representation.
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If the header field name does not match a header field name entry,
the value 0 is represented on 6 bits followed by the header field
name (Section 4.1.2).
The header field name representation is followed by the header field
value represented as a literal string as described in Section 4.1.2.
4.3.2. Literal Header Field with Incremental Indexing
A literal header field with incremental indexing adds a new entry to
the header table.
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 0 | 0 | Index (6+) |
+---+---+---+-------------------+
| Value Length (8+) |
+-------------------------------+
| Value String (Length octets) |
+-------------------------------+
Literal Header Field with Incremental Indexing -
Indexed Name
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 0 | 0 | 0 |
+---+---+---+-------------------+
| Name Length (8+) |
+-------------------------------+
| Name String (Length octets) |
+-------------------------------+
| Value Length (8+) |
+-------------------------------+
| Value String (Length octets) |
+-------------------------------+
Literal Header Field with Incremental Indexing -
New Name
This representation starts with the '00' 2-bit pattern.
If the header field name matches the header field name of a (name,
value) pair stored in the header table or static table, the index of
the pair increased by one (index + 1) is represented as an integer
with a 6-bit prefix.
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If the header field name does not match a header field name entry,
the value 0 is represented on 6 bits followed by the header field
name (Section 4.1.2).
The header field name representation is followed by the header field
value represented as a literal string as described in Section 4.1.2.
5. Security Considerations
This compressor exists to solve security issues present in stream
compressors such as DEFLATE whereby the compression context can be
efficiently probed to reveal secrets. A conformant implementation of
this specification should be fairly safe against that kind of attack,
as the reaping of any information from the compression context
requires more work than guessing and verifying the plaintext data
directly with the server. As with any secret, however, the longer
the length of the secret, the more difficult the secret is to guess.
It is inadvisable to have short cookies that are relied upon to
remain secret for any duration of time.
A proper security-conscious implementation will also need to prevent
timing attacks by ensuring that the amount of time it takes to do
string comparisons is always a function of the total length of the
strings, and not a function of the number of matched characters.
A decoder needs to ensure that larger values or encodings of integers
do not permit exploitation. Decoders MUST limit the size of
integers, both in value and encoded length, that it accepts (see
Section 4.1.1).
Another common security problem is when the remote endpoint
successfully causes the local endpoint to exhaust its memory. This
compressor attempts to deal with the most obvious ways that this
could occur by limiting both the peak and the steady-state amount of
memory consumed in the compressor state, by providing ways for the
application to consume/flush the emitted header fields in small
chunks, and by considering overhead in the state size calculation.
Implementors must still be careful in the creation of APIs to an
implementation of this compressor by ensuring that header field keys
and values are either emitted as a stream, or that the compression
implementation have a limit on the maximum size of a key or value.
Failure to implement these kinds of safeguards may still result in a
scenario where the local endpoint exhausts its memory.
6. References
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6.1. Normative References
[HTTP-p1] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
draft-ietf-httpbis-p1-messaging-24 (work in progress),
September 2013.
[HTTP2] Belshe, M., Peon, R., Thomson, M., and A. Melnikov,
"Hypertext Transfer Protocol version 2.0",
draft-ietf-httpbis-http2-06 (work in progress),
August 2013.
6.2. Informative References
[CANON] Schwartz, E. and B. Kallick, "Generating a canonical
prefix encoding", Communications of the ACM Volume 7 Issue
3, pp. 166-169, March 1964,
<http://dl.acm.org/citation.cfm?id=363991>.
[CRIME] Rizzo, J. and T. Duong, "The Crime Attack",
September 2012, <https://docs.google.com/a/twist.com/
presentation/d/
11eBmGiHbYcHR9gL5nDyZChu_-lCa2GizeuOfaLU2HOU/
edit#slide=id.g1eb6c1b5_3_6>.
[HUFF] Huffman, D., "A Method for the Construction of Minimim
Redundancy Codes", Proceedings of the Institute of Radio
Engineers Volume 40, Number 9, pp. 1098-1101,
September 1952, <http://ieeexplore.ieee.org/xpl/
articleDetails.jsp?arnumber=4051119>.
[PERF1] Belshe, M., "IETF83: SPDY and What to Consider for
HTTP/2.0", March 2012, <http://www.ietf.org/proceedings/
83/slides/slides-83-httpbis-3>.
[PERF2] McManus, P., "SPDY: What I Like About You",
September 2011, <http://bitsup.blogspot.com/2011/09/
spdy-what-i-like-about-you.html>.
[SPDY] Belshe, M. and R. Peon, "SPDY Protocol",
draft-mbelshe-httpbis-spdy-00 (work in progress),
February 2012.
URIs
[1] <http://en.wikipedia.org/wiki/Variable-length_quantity>
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Appendix A. Change Log (to be removed by RFC Editor before publication
A.1. Since draft-ietf-httpbis-header-compression-03
o A large number of editorial changes; changed the description of
evicting/adding new entries.
o Removed substitution indexing
o Changed 'initial headers' to 'static headers', as per issue #258
o Merged 'request' and 'response' static headers, as per issue #259
o Changed text to indicate that new headers are added at index 0 and
expire from the largest index, as per issue #233
A.2. Since draft-ietf-httpbis-header-compression-02
o Corrected error in integer encoding pseudocode.
A.3. Since draft-ietf-httpbis-header-compression-01
o Refactored of Header Encoding Section: split definitions and
processing rule.
o Backward incompatible change: Updated reference set management as
per issue #214. This changes how the interaction between the
reference set and eviction works. This also changes the working
of the reference set in some specific cases.
o Backward incompatible change: modified initial header list, as per
issue #188.
o Added example of 32 bytes entry structure (issue #191).
o Added Header Set Completion section. Reflowed some text.
Clarified some writing which was akward. Added text about
duplicate header entry encoding. Clarified some language w.r.t
Header Set. Changed x-my-header to mynewheader. Added text in the
HeaderEmission section indicating that the application may also be
able to free up memory more quickly. Added information in
Security Considerations section.
A.4. Since draft-ietf-httpbis-header-compression-01
Fixed bug/omission in integer representation algorithm.
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Changed the document title.
Header matching text rewritten.
Changed the definition of header emission.
Changed the name of the setting which dictates how much memory the
compression context should use.
Removed "specific use cases" section
Corrected erroneous statement about what index can be contained in
one byte
Added descriptions of opcodes
Removed security claims from introduction.
Appendix B. Static Table
The static table consists of an unchangable ordered list of (name,
value) pairs. The first entry in the table is always represented by
the index len(header table), and the last entry in the table is
represented by the index len(header table)+len(static table)-1.
[[anchor9: The ordering of these tables is currently arbitrary. The
tables in this section should be updated and ordered such that the
table entries with the smallest indices are those which, based on a
statistical analysis of the frequency of use weighted by size,
achieve the largest decrease in bytes transmitted subject to HTTP 2.0
header field rules (like removal of some header fields). This set of
header fields is currently very likely incomplete, and should be made
complete.]]
The following table lists the pre-defined header fields that make-up
the static header table.
+-------+-----------------------------+--------------+
| Index | Header Name | Header Value |
+-------+-----------------------------+--------------+
| 0 | :authority | |
| 1 | :method | GET |
| 2 | :method | POST |
| 3 | :path | / |
| 4 | :path | /index.html |
| 5 | :scheme | http |
| 6 | :scheme | https |
| 7 | :status | 200 |
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| 8 | :status | 500 |
| 9 | :status | 404 |
| 10 | :status | 403 |
| 11 | :status | 400 |
| 12 | :status | 401 |
| 13 | accept-charset | |
| 14 | accept-encoding | |
| 15 | accept-language | |
| 16 | accept-ranges | |
| 17 | accept | |
| 18 | access-control-allow-origin | |
| 19 | age | |
| 20 | allow | |
| 21 | authorization | |
| 22 | cache-control | |
| 23 | content-disposition | |
| 24 | content-encoding | |
| 25 | content-language | |
| 26 | content-length | |
| 27 | content-location | |
| 28 | content-range | |
| 29 | content-type | |
| 30 | cookie | |
| 31 | date | |
| 32 | etag | |
| 33 | expect | |
| 34 | expires | |
| 35 | from | |
| 36 | if-match | |
| 37 | if-modified-since | |
| 38 | if-none-match | |
| 39 | if-range | |
| 40 | if-unmodified-since | |
| 41 | last-modified | |
| 42 | link | |
| 43 | location | |
| 44 | max-forwards | |
| 45 | proxy-authenticate | |
| 46 | proxy-authorization | |
| 47 | range | |
| 48 | referer | |
| 49 | refresh | |
| 50 | retry-after | |
| 51 | server | |
| 52 | set-cookie | |
| 53 | strict-transport-security | |
| 54 | transfer-encoding | |
| 55 | user-agent | |
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| 56 | vary | |
| 57 | via | |
| 58 | www-authenticate | |
+-------+-----------------------------+--------------+
Table 1: Static Table Entries
The table give the index of each entry in the static table. The full
index of each entry, to be used for encoding a reference to this
entry, is computed by adding the number of entries in the header
table to this index.
Appendix C. Huffman Codes For Requests
The following Huffman codes are used when encoding string literals in
the client to server direction.
[[anchor10: This table is out of date and needs updating. In
particular, EOS needs to be at least 7-bits long and currently is
not.]]
aligned aligned
to len to len
MSB in LSB in
sym as bits bits as hex bits
( 0) |11111111|11111111|11110111|010 [27] 7ffffba [27]
( 1) |11111111|11111111|11110111|011 [27] 7ffffbb [27]
( 2) |11111111|11111111|11110111|100 [27] 7ffffbc [27]
( 3) |11111111|11111111|11110111|101 [27] 7ffffbd [27]
( 4) |11111111|11111111|11110111|110 [27] 7ffffbe [27]
( 5) |11111111|11111111|11110111|111 [27] 7ffffbf [27]
( 6) |11111111|11111111|11111000|000 [27] 7ffffc0 [27]
( 7) |11111111|11111111|11111000|001 [27] 7ffffc1 [27]
( 8) |11111111|11111111|11111000|010 [27] 7ffffc2 [27]
( 9) |11111111|11111111|11111000|011 [27] 7ffffc3 [27]
( 10) |11111111|11111111|11111000|100 [27] 7ffffc4 [27]
( 11) |11111111|11111111|11111000|101 [27] 7ffffc5 [27]
( 12) |11111111|11111111|11111000|110 [27] 7ffffc6 [27]
( 13) |11111111|11111111|11111000|111 [27] 7ffffc7 [27]
( 14) |11111111|11111111|11111001|000 [27] 7ffffc8 [27]
( 15) |11111111|11111111|11111001|001 [27] 7ffffc9 [27]
( 16) |11111111|11111111|11111001|010 [27] 7ffffca [27]
( 17) |11111111|11111111|11111001|011 [27] 7ffffcb [27]
( 18) |11111111|11111111|11111001|100 [27] 7ffffcc [27]
( 19) |11111111|11111111|11111001|101 [27] 7ffffcd [27]
( 20) |11111111|11111111|11111001|110 [27] 7ffffce [27]
( 21) |11111111|11111111|11111001|111 [27] 7ffffcf [27]
( 22) |11111111|11111111|11111010|000 [27] 7ffffd0 [27]
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( 23) |11111111|11111111|11111010|001 [27] 7ffffd1 [27]
( 24) |11111111|11111111|11111010|010 [27] 7ffffd2 [27]
( 25) |11111111|11111111|11111010|011 [27] 7ffffd3 [27]
( 26) |11111111|11111111|11111010|100 [27] 7ffffd4 [27]
( 27) |11111111|11111111|11111010|101 [27] 7ffffd5 [27]
( 28) |11111111|11111111|11111010|110 [27] 7ffffd6 [27]
( 29) |11111111|11111111|11111010|111 [27] 7ffffd7 [27]
( 30) |11111111|11111111|11111011|000 [27] 7ffffd8 [27]
( 31) |11111111|11111111|11111011|001 [27] 7ffffd9 [27]
' ' ( 32) |11101000| [8] e8 [8]
'!' ( 33) |11111111|1100 [12] ffc [12]
'"' ( 34) |11111111|111010 [14] 3ffa [14]
'#' ( 35) |11111111|1111100 [15] 7ffc [15]
'$' ( 36) |11111111|1111101 [15] 7ffd [15]
'%' ( 37) |100100 [6] 24 [6]
'&' ( 38) |1101110 [7] 6e [7]
''' ( 39) |11111111|1111110 [15] 7ffe [15]
'(' ( 40) |11111111|010 [11] 7fa [11]
')' ( 41) |11111111|011 [11] 7fb [11]
'*' ( 42) |11111110|10 [10] 3fa [10]
'+' ( 43) |11111111|100 [11] 7fc [11]
',' ( 44) |11101001| [8] e9 [8]
'-' ( 45) |100101 [6] 25 [6]
'.' ( 46) |00100 [5] 4 [5]
'/' ( 47) |0000 [4] 0 [4]
'0' ( 48) |00101 [5] 5 [5]
'1' ( 49) |00110 [5] 6 [5]
'2' ( 50) |00111 [5] 7 [5]
'3' ( 51) |100110 [6] 26 [6]
'4' ( 52) |100111 [6] 27 [6]
'5' ( 53) |101000 [6] 28 [6]
'6' ( 54) |101001 [6] 29 [6]
'7' ( 55) |101010 [6] 2a [6]
'8' ( 56) |101011 [6] 2b [6]
'9' ( 57) |101100 [6] 2c [6]
':' ( 58) |11110110|0 [9] 1ec [9]
';' ( 59) |11101010| [8] ea [8]
'<' ( 60) |11111111|11111111|10 [18] 3fffe [18]
'=' ( 61) |101101 [6] 2d [6]
'>' ( 62) |11111111|11111110|0 [17] 1fffc [17]
'?' ( 63) |11110110|1 [9] 1ed [9]
'@' ( 64) |11111111|111011 [14] 3ffb [14]
'A' ( 65) |1101111 [7] 6f [7]
'B' ( 66) |11101011| [8] eb [8]
'C' ( 67) |11101100| [8] ec [8]
'D' ( 68) |11101101| [8] ed [8]
'E' ( 69) |11101110| [8] ee [8]
'F' ( 70) |1110000 [7] 70 [7]
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'G' ( 71) |11110111|0 [9] 1ee [9]
'H' ( 72) |11110111|1 [9] 1ef [9]
'I' ( 73) |11111000|0 [9] 1f0 [9]
'J' ( 74) |11111000|1 [9] 1f1 [9]
'K' ( 75) |11111110|11 [10] 3fb [10]
'L' ( 76) |11111001|0 [9] 1f2 [9]
'M' ( 77) |11101111| [8] ef [8]
'N' ( 78) |11111001|1 [9] 1f3 [9]
'O' ( 79) |11111010|0 [9] 1f4 [9]
'P' ( 80) |11111010|1 [9] 1f5 [9]
'Q' ( 81) |11111011|0 [9] 1f6 [9]
'R' ( 82) |11111011|1 [9] 1f7 [9]
'S' ( 83) |11110000| [8] f0 [8]
'T' ( 84) |11110001| [8] f1 [8]
'U' ( 85) |11111100|0 [9] 1f8 [9]
'V' ( 86) |11111100|1 [9] 1f9 [9]
'W' ( 87) |11111101|0 [9] 1fa [9]
'X' ( 88) |11111101|1 [9] 1fb [9]
'Y' ( 89) |11111110|0 [9] 1fc [9]
'Z' ( 90) |11111111|00 [10] 3fc [10]
'[' ( 91) |11111111|111100 [14] 3ffc [14]
'\' ( 92) |11111111|11111111|11111011|010 [27] 7ffffda [27]
']' ( 93) |11111111|11100 [13] 1ffc [13]
'^' ( 94) |11111111|111101 [14] 3ffd [14]
'_' ( 95) |101110 [6] 2e [6]
'`' ( 96) |11111111|11111111|110 [19] 7fffe [19]
'a' ( 97) |01000 [5] 8 [5]
'b' ( 98) |101111 [6] 2f [6]
'c' ( 99) |01001 [5] 9 [5]
'd' (100) |110000 [6] 30 [6]
'e' (101) |0001 [4] 1 [4]
'f' (102) |110001 [6] 31 [6]
'g' (103) |110010 [6] 32 [6]
'h' (104) |110011 [6] 33 [6]
'i' (105) |01010 [5] a [5]
'j' (106) |1110001 [7] 71 [7]
'k' (107) |1110010 [7] 72 [7]
'l' (108) |01011 [5] b [5]
'm' (109) |110100 [6] 34 [6]
'n' (110) |01100 [5] c [5]
'o' (111) |01101 [5] d [5]
'p' (112) |01110 [5] e [5]
'q' (113) |11110010| [8] f2 [8]
'r' (114) |01111 [5] f [5]
's' (115) |10000 [5] 10 [5]
't' (116) |10001 [5] 11 [5]
'u' (117) |110101 [6] 35 [6]
'v' (118) |1110011 [7] 73 [7]
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'w' (119) |110110 [6] 36 [6]
'x' (120) |11110011| [8] f3 [8]
'y' (121) |11110100| [8] f4 [8]
'z' (122) |11110101| [8] f5 [8]
'{' (123) |11111111|11111110|1 [17] 1fffd [17]
'|' (124) |11111111|101 [11] 7fd [11]
'}' (125) |11111111|11111111|0 [17] 1fffe [17]
'~' (126) |11111111|1101 [12] ffd [12]
(127) |11111111|11111111|11111011|011 [27] 7ffffdb [27]
(128) |11111111|11111111|11111011|100 [27] 7ffffdc [27]
(129) |11111111|11111111|11111011|101 [27] 7ffffdd [27]
(130) |11111111|11111111|11111011|110 [27] 7ffffde [27]
(131) |11111111|11111111|11111011|111 [27] 7ffffdf [27]
(132) |11111111|11111111|11111100|000 [27] 7ffffe0 [27]
(133) |11111111|11111111|11111100|001 [27] 7ffffe1 [27]
(134) |11111111|11111111|11111100|010 [27] 7ffffe2 [27]
(135) |11111111|11111111|11111100|011 [27] 7ffffe3 [27]
(136) |11111111|11111111|11111100|100 [27] 7ffffe4 [27]
(137) |11111111|11111111|11111100|101 [27] 7ffffe5 [27]
(138) |11111111|11111111|11111100|110 [27] 7ffffe6 [27]
(139) |11111111|11111111|11111100|111 [27] 7ffffe7 [27]
(140) |11111111|11111111|11111101|000 [27] 7ffffe8 [27]
(141) |11111111|11111111|11111101|001 [27] 7ffffe9 [27]
(142) |11111111|11111111|11111101|010 [27] 7ffffea [27]
(143) |11111111|11111111|11111101|011 [27] 7ffffeb [27]
(144) |11111111|11111111|11111101|100 [27] 7ffffec [27]
(145) |11111111|11111111|11111101|101 [27] 7ffffed [27]
(146) |11111111|11111111|11111101|110 [27] 7ffffee [27]
(147) |11111111|11111111|11111101|111 [27] 7ffffef [27]
(148) |11111111|11111111|11111110|000 [27] 7fffff0 [27]
(149) |11111111|11111111|11111110|001 [27] 7fffff1 [27]
(150) |11111111|11111111|11111110|010 [27] 7fffff2 [27]
(151) |11111111|11111111|11111110|011 [27] 7fffff3 [27]
(152) |11111111|11111111|11111110|100 [27] 7fffff4 [27]
(153) |11111111|11111111|11111110|101 [27] 7fffff5 [27]
(154) |11111111|11111111|11111110|110 [27] 7fffff6 [27]
(155) |11111111|11111111|11111110|111 [27] 7fffff7 [27]
(156) |11111111|11111111|11111111|000 [27] 7fffff8 [27]
(157) |11111111|11111111|11111111|001 [27] 7fffff9 [27]
(158) |11111111|11111111|11111111|010 [27] 7fffffa [27]
(159) |11111111|11111111|11111111|011 [27] 7fffffb [27]
(160) |11111111|11111111|11111111|100 [27] 7fffffc [27]
(161) |11111111|11111111|11111111|101 [27] 7fffffd [27]
(162) |11111111|11111111|11111111|110 [27] 7fffffe [27]
(163) |11111111|11111111|11111111|111 [27] 7ffffff [27]
(164) |11111111|11111111|11100000|00 [26] 3ffff80 [26]
(165) |11111111|11111111|11100000|01 [26] 3ffff81 [26]
(166) |11111111|11111111|11100000|10 [26] 3ffff82 [26]
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(167) |11111111|11111111|11100000|11 [26] 3ffff83 [26]
(168) |11111111|11111111|11100001|00 [26] 3ffff84 [26]
(169) |11111111|11111111|11100001|01 [26] 3ffff85 [26]
(170) |11111111|11111111|11100001|10 [26] 3ffff86 [26]
(171) |11111111|11111111|11100001|11 [26] 3ffff87 [26]
(172) |11111111|11111111|11100010|00 [26] 3ffff88 [26]
(173) |11111111|11111111|11100010|01 [26] 3ffff89 [26]
(174) |11111111|11111111|11100010|10 [26] 3ffff8a [26]
(175) |11111111|11111111|11100010|11 [26] 3ffff8b [26]
(176) |11111111|11111111|11100011|00 [26] 3ffff8c [26]
(177) |11111111|11111111|11100011|01 [26] 3ffff8d [26]
(178) |11111111|11111111|11100011|10 [26] 3ffff8e [26]
(179) |11111111|11111111|11100011|11 [26] 3ffff8f [26]
(180) |11111111|11111111|11100100|00 [26] 3ffff90 [26]
(181) |11111111|11111111|11100100|01 [26] 3ffff91 [26]
(182) |11111111|11111111|11100100|10 [26] 3ffff92 [26]
(183) |11111111|11111111|11100100|11 [26] 3ffff93 [26]
(184) |11111111|11111111|11100101|00 [26] 3ffff94 [26]
(185) |11111111|11111111|11100101|01 [26] 3ffff95 [26]
(186) |11111111|11111111|11100101|10 [26] 3ffff96 [26]
(187) |11111111|11111111|11100101|11 [26] 3ffff97 [26]
(188) |11111111|11111111|11100110|00 [26] 3ffff98 [26]
(189) |11111111|11111111|11100110|01 [26] 3ffff99 [26]
(190) |11111111|11111111|11100110|10 [26] 3ffff9a [26]
(191) |11111111|11111111|11100110|11 [26] 3ffff9b [26]
(192) |11111111|11111111|11100111|00 [26] 3ffff9c [26]
(193) |11111111|11111111|11100111|01 [26] 3ffff9d [26]
(194) |11111111|11111111|11100111|10 [26] 3ffff9e [26]
(195) |11111111|11111111|11100111|11 [26] 3ffff9f [26]
(196) |11111111|11111111|11101000|00 [26] 3ffffa0 [26]
(197) |11111111|11111111|11101000|01 [26] 3ffffa1 [26]
(198) |11111111|11111111|11101000|10 [26] 3ffffa2 [26]
(199) |11111111|11111111|11101000|11 [26] 3ffffa3 [26]
(200) |11111111|11111111|11101001|00 [26] 3ffffa4 [26]
(201) |11111111|11111111|11101001|01 [26] 3ffffa5 [26]
(202) |11111111|11111111|11101001|10 [26] 3ffffa6 [26]
(203) |11111111|11111111|11101001|11 [26] 3ffffa7 [26]
(204) |11111111|11111111|11101010|00 [26] 3ffffa8 [26]
(205) |11111111|11111111|11101010|01 [26] 3ffffa9 [26]
(206) |11111111|11111111|11101010|10 [26] 3ffffaa [26]
(207) |11111111|11111111|11101010|11 [26] 3ffffab [26]
(208) |11111111|11111111|11101011|00 [26] 3ffffac [26]
(209) |11111111|11111111|11101011|01 [26] 3ffffad [26]
(210) |11111111|11111111|11101011|10 [26] 3ffffae [26]
(211) |11111111|11111111|11101011|11 [26] 3ffffaf [26]
(212) |11111111|11111111|11101100|00 [26] 3ffffb0 [26]
(213) |11111111|11111111|11101100|01 [26] 3ffffb1 [26]
(214) |11111111|11111111|11101100|10 [26] 3ffffb2 [26]
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(215) |11111111|11111111|11101100|11 [26] 3ffffb3 [26]
(216) |11111111|11111111|11101101|00 [26] 3ffffb4 [26]
(217) |11111111|11111111|11101101|01 [26] 3ffffb5 [26]
(218) |11111111|11111111|11101101|10 [26] 3ffffb6 [26]
(219) |11111111|11111111|11101101|11 [26] 3ffffb7 [26]
(220) |11111111|11111111|11101110|00 [26] 3ffffb8 [26]
(221) |11111111|11111111|11101110|01 [26] 3ffffb9 [26]
(222) |11111111|11111111|11101110|10 [26] 3ffffba [26]
(223) |11111111|11111111|11101110|11 [26] 3ffffbb [26]
(224) |11111111|11111111|11101111|00 [26] 3ffffbc [26]
(225) |11111111|11111111|11101111|01 [26] 3ffffbd [26]
(226) |11111111|11111111|11101111|10 [26] 3ffffbe [26]
(227) |11111111|11111111|11101111|11 [26] 3ffffbf [26]
(228) |11111111|11111111|11110000|00 [26] 3ffffc0 [26]
(229) |11111111|11111111|11110000|01 [26] 3ffffc1 [26]
(230) |11111111|11111111|11110000|10 [26] 3ffffc2 [26]
(231) |11111111|11111111|11110000|11 [26] 3ffffc3 [26]
(232) |11111111|11111111|11110001|00 [26] 3ffffc4 [26]
(233) |11111111|11111111|11110001|01 [26] 3ffffc5 [26]
(234) |11111111|11111111|11110001|10 [26] 3ffffc6 [26]
(235) |11111111|11111111|11110001|11 [26] 3ffffc7 [26]
(236) |11111111|11111111|11110010|00 [26] 3ffffc8 [26]
(237) |11111111|11111111|11110010|01 [26] 3ffffc9 [26]
(238) |11111111|11111111|11110010|10 [26] 3ffffca [26]
(239) |11111111|11111111|11110010|11 [26] 3ffffcb [26]
(240) |11111111|11111111|11110011|00 [26] 3ffffcc [26]
(241) |11111111|11111111|11110011|01 [26] 3ffffcd [26]
(242) |11111111|11111111|11110011|10 [26] 3ffffce [26]
(243) |11111111|11111111|11110011|11 [26] 3ffffcf [26]
(244) |11111111|11111111|11110100|00 [26] 3ffffd0 [26]
(245) |11111111|11111111|11110100|01 [26] 3ffffd1 [26]
(246) |11111111|11111111|11110100|10 [26] 3ffffd2 [26]
(247) |11111111|11111111|11110100|11 [26] 3ffffd3 [26]
(248) |11111111|11111111|11110101|00 [26] 3ffffd4 [26]
(249) |11111111|11111111|11110101|01 [26] 3ffffd5 [26]
(250) |11111111|11111111|11110101|10 [26] 3ffffd6 [26]
(251) |11111111|11111111|11110101|11 [26] 3ffffd7 [26]
(252) |11111111|11111111|11110110|00 [26] 3ffffd8 [26]
(253) |11111111|11111111|11110110|01 [26] 3ffffd9 [26]
(254) |11111111|11111111|11110110|10 [26] 3ffffda [26]
(255) |11111111|11111111|11110110|11 [26] 3ffffdb [26]
EOS (256) |11111111|11111111|11110111|00 [26] 3ffffdc [26]
Peon & Ruellan Expires April 24, 2014 [Page 27]
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Appendix D. Huffman Codes for Responses
The following Huffman codes are used when encoding string literals in
the server to client direction.
[[anchor11: This table is out of date and needs updating. In
particular, EOS needs to be at least 7-bits long and currently is
not.]]
aligned aligned
to len to len
MSB in LSB in
sym as bits bits as hex bits
( 0) |11111111|11111111|11011110|0 [25] 1ffffbc [25]
( 1) |11111111|11111111|11011110|1 [25] 1ffffbd [25]
( 2) |11111111|11111111|11011111|0 [25] 1ffffbe [25]
( 3) |11111111|11111111|11011111|1 [25] 1ffffbf [25]
( 4) |11111111|11111111|11100000|0 [25] 1ffffc0 [25]
( 5) |11111111|11111111|11100000|1 [25] 1ffffc1 [25]
( 6) |11111111|11111111|11100001|0 [25] 1ffffc2 [25]
( 7) |11111111|11111111|11100001|1 [25] 1ffffc3 [25]
( 8) |11111111|11111111|11100010|0 [25] 1ffffc4 [25]
( 9) |11111111|11111111|11100010|1 [25] 1ffffc5 [25]
( 10) |11111111|11111111|11100011|0 [25] 1ffffc6 [25]
( 11) |11111111|11111111|11100011|1 [25] 1ffffc7 [25]
( 12) |11111111|11111111|11100100|0 [25] 1ffffc8 [25]
( 13) |11111111|11111111|11100100|1 [25] 1ffffc9 [25]
( 14) |11111111|11111111|11100101|0 [25] 1ffffca [25]
( 15) |11111111|11111111|11100101|1 [25] 1ffffcb [25]
( 16) |11111111|11111111|11100110|0 [25] 1ffffcc [25]
( 17) |11111111|11111111|11100110|1 [25] 1ffffcd [25]
( 18) |11111111|11111111|11100111|0 [25] 1ffffce [25]
( 19) |11111111|11111111|11100111|1 [25] 1ffffcf [25]
( 20) |11111111|11111111|11101000|0 [25] 1ffffd0 [25]
( 21) |11111111|11111111|11101000|1 [25] 1ffffd1 [25]
( 22) |11111111|11111111|11101001|0 [25] 1ffffd2 [25]
( 23) |11111111|11111111|11101001|1 [25] 1ffffd3 [25]
( 24) |11111111|11111111|11101010|0 [25] 1ffffd4 [25]
( 25) |11111111|11111111|11101010|1 [25] 1ffffd5 [25]
( 26) |11111111|11111111|11101011|0 [25] 1ffffd6 [25]
( 27) |11111111|11111111|11101011|1 [25] 1ffffd7 [25]
( 28) |11111111|11111111|11101100|0 [25] 1ffffd8 [25]
( 29) |11111111|11111111|11101100|1 [25] 1ffffd9 [25]
( 30) |11111111|11111111|11101101|0 [25] 1ffffda [25]
( 31) |11111111|11111111|11101101|1 [25] 1ffffdb [25]
' ' ( 32) |0000 [4] 0 [4]
'!' ( 33) |11111111|1010 [12] ffa [12]
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'"' ( 34) |1101010 [7] 6a [7]
'#' ( 35) |11111111|11010 [13] 1ffa [13]
'$' ( 36) |11111111|111100 [14] 3ffc [14]
'%' ( 37) |11110110|0 [9] 1ec [9]
'&' ( 38) |11111110|00 [10] 3f8 [10]
''' ( 39) |11111111|11011 [13] 1ffb [13]
'(' ( 40) |11110110|1 [9] 1ed [9]
')' ( 41) |11110111|0 [9] 1ee [9]
'*' ( 42) |11111111|1011 [12] ffb [12]
'+' ( 43) |11111111|010 [11] 7fa [11]
',' ( 44) |100010 [6] 22 [6]
'-' ( 45) |100011 [6] 23 [6]
'.' ( 46) |100100 [6] 24 [6]
'/' ( 47) |1101011 [7] 6b [7]
'0' ( 48) |0001 [4] 1 [4]
'1' ( 49) |0010 [4] 2 [4]
'2' ( 50) |0011 [4] 3 [4]
'3' ( 51) |01000 [5] 8 [5]
'4' ( 52) |01001 [5] 9 [5]
'5' ( 53) |01010 [5] a [5]
'6' ( 54) |100101 [6] 25 [6]
'7' ( 55) |100110 [6] 26 [6]
'8' ( 56) |01011 [5] b [5]
'9' ( 57) |01100 [5] c [5]
':' ( 58) |01101 [5] d [5]
';' ( 59) |11110111|1 [9] 1ef [9]
'<' ( 60) |11111111|11111010| [16] fffa [16]
'=' ( 61) |1101100 [7] 6c [7]
'>' ( 62) |11111111|11100 [13] 1ffc [13]
'?' ( 63) |11111111|1100 [12] ffc [12]
'@' ( 64) |11111111|11111011| [16] fffb [16]
'A' ( 65) |1101101 [7] 6d [7]
'B' ( 66) |11101010| [8] ea [8]
'C' ( 67) |11101011| [8] eb [8]
'D' ( 68) |11101100| [8] ec [8]
'E' ( 69) |11101101| [8] ed [8]
'F' ( 70) |11101110| [8] ee [8]
'G' ( 71) |100111 [6] 27 [6]
'H' ( 72) |11111000|0 [9] 1f0 [9]
'I' ( 73) |11101111| [8] ef [8]
'J' ( 74) |11110000| [8] f0 [8]
'K' ( 75) |11111110|01 [10] 3f9 [10]
'L' ( 76) |11111000|1 [9] 1f1 [9]
'M' ( 77) |101000 [6] 28 [6]
'N' ( 78) |11110001| [8] f1 [8]
'O' ( 79) |11110010| [8] f2 [8]
'P' ( 80) |11111001|0 [9] 1f2 [9]
'Q' ( 81) |11111110|10 [10] 3fa [10]
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'R' ( 82) |11111001|1 [9] 1f3 [9]
'S' ( 83) |101001 [6] 29 [6]
'T' ( 84) |01110 [5] e [5]
'U' ( 85) |11111010|0 [9] 1f4 [9]
'V' ( 86) |11111010|1 [9] 1f5 [9]
'W' ( 87) |11110011| [8] f3 [8]
'X' ( 88) |11111110|11 [10] 3fb [10]
'Y' ( 89) |11111011|0 [9] 1f6 [9]
'Z' ( 90) |11111111|00 [10] 3fc [10]
'[' ( 91) |11111111|011 [11] 7fb [11]
'\' ( 92) |11111111|11101 [13] 1ffd [13]
']' ( 93) |11111111|100 [11] 7fc [11]
'^' ( 94) |11111111|1111100 [15] 7ffc [15]
'_' ( 95) |11111011|1 [9] 1f7 [9]
'`' ( 96) |11111111|11111111|0 [17] 1fffe [17]
'a' ( 97) |01111 [5] f [5]
'b' ( 98) |1101110 [7] 6e [7]
'c' ( 99) |101010 [6] 2a [6]
'd' (100) |101011 [6] 2b [6]
'e' (101) |10000 [5] 10 [5]
'f' (102) |1101111 [7] 6f [7]
'g' (103) |1110000 [7] 70 [7]
'h' (104) |1110001 [7] 71 [7]
'i' (105) |101100 [6] 2c [6]
'j' (106) |11111100|0 [9] 1f8 [9]
'k' (107) |11111100|1 [9] 1f9 [9]
'l' (108) |1110010 [7] 72 [7]
'm' (109) |101101 [6] 2d [6]
'n' (110) |101110 [6] 2e [6]
'o' (111) |101111 [6] 2f [6]
'p' (112) |110000 [6] 30 [6]
'q' (113) |11111101|0 [9] 1fa [9]
'r' (114) |110001 [6] 31 [6]
's' (115) |110010 [6] 32 [6]
't' (116) |110011 [6] 33 [6]
'u' (117) |110100 [6] 34 [6]
'v' (118) |1110011 [7] 73 [7]
'w' (119) |11110100| [8] f4 [8]
'x' (120) |1110100 [7] 74 [7]
'y' (121) |11110101| [8] f5 [8]
'z' (122) |11111101|1 [9] 1fb [9]
'{' (123) |11111111|11111100| [16] fffc [16]
'|' (124) |11111111|111101 [14] 3ffd [14]
'}' (125) |11111111|11111101| [16] fffd [16]
'~' (126) |11111111|11111110| [16] fffe [16]
(127) |11111111|11111111|11101110|0 [25] 1ffffdc [25]
(128) |11111111|11111111|11101110|1 [25] 1ffffdd [25]
(129) |11111111|11111111|11101111|0 [25] 1ffffde [25]
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(130) |11111111|11111111|11101111|1 [25] 1ffffdf [25]
(131) |11111111|11111111|11110000|0 [25] 1ffffe0 [25]
(132) |11111111|11111111|11110000|1 [25] 1ffffe1 [25]
(133) |11111111|11111111|11110001|0 [25] 1ffffe2 [25]
(134) |11111111|11111111|11110001|1 [25] 1ffffe3 [25]
(135) |11111111|11111111|11110010|0 [25] 1ffffe4 [25]
(136) |11111111|11111111|11110010|1 [25] 1ffffe5 [25]
(137) |11111111|11111111|11110011|0 [25] 1ffffe6 [25]
(138) |11111111|11111111|11110011|1 [25] 1ffffe7 [25]
(139) |11111111|11111111|11110100|0 [25] 1ffffe8 [25]
(140) |11111111|11111111|11110100|1 [25] 1ffffe9 [25]
(141) |11111111|11111111|11110101|0 [25] 1ffffea [25]
(142) |11111111|11111111|11110101|1 [25] 1ffffeb [25]
(143) |11111111|11111111|11110110|0 [25] 1ffffec [25]
(144) |11111111|11111111|11110110|1 [25] 1ffffed [25]
(145) |11111111|11111111|11110111|0 [25] 1ffffee [25]
(146) |11111111|11111111|11110111|1 [25] 1ffffef [25]
(147) |11111111|11111111|11111000|0 [25] 1fffff0 [25]
(148) |11111111|11111111|11111000|1 [25] 1fffff1 [25]
(149) |11111111|11111111|11111001|0 [25] 1fffff2 [25]
(150) |11111111|11111111|11111001|1 [25] 1fffff3 [25]
(151) |11111111|11111111|11111010|0 [25] 1fffff4 [25]
(152) |11111111|11111111|11111010|1 [25] 1fffff5 [25]
(153) |11111111|11111111|11111011|0 [25] 1fffff6 [25]
(154) |11111111|11111111|11111011|1 [25] 1fffff7 [25]
(155) |11111111|11111111|11111100|0 [25] 1fffff8 [25]
(156) |11111111|11111111|11111100|1 [25] 1fffff9 [25]
(157) |11111111|11111111|11111101|0 [25] 1fffffa [25]
(158) |11111111|11111111|11111101|1 [25] 1fffffb [25]
(159) |11111111|11111111|11111110|0 [25] 1fffffc [25]
(160) |11111111|11111111|11111110|1 [25] 1fffffd [25]
(161) |11111111|11111111|11111111|0 [25] 1fffffe [25]
(162) |11111111|11111111|11111111|1 [25] 1ffffff [25]
(163) |11111111|11111111|10000000| [24] ffff80 [24]
(164) |11111111|11111111|10000001| [24] ffff81 [24]
(165) |11111111|11111111|10000010| [24] ffff82 [24]
(166) |11111111|11111111|10000011| [24] ffff83 [24]
(167) |11111111|11111111|10000100| [24] ffff84 [24]
(168) |11111111|11111111|10000101| [24] ffff85 [24]
(169) |11111111|11111111|10000110| [24] ffff86 [24]
(170) |11111111|11111111|10000111| [24] ffff87 [24]
(171) |11111111|11111111|10001000| [24] ffff88 [24]
(172) |11111111|11111111|10001001| [24] ffff89 [24]
(173) |11111111|11111111|10001010| [24] ffff8a [24]
(174) |11111111|11111111|10001011| [24] ffff8b [24]
(175) |11111111|11111111|10001100| [24] ffff8c [24]
(176) |11111111|11111111|10001101| [24] ffff8d [24]
(177) |11111111|11111111|10001110| [24] ffff8e [24]
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(178) |11111111|11111111|10001111| [24] ffff8f [24]
(179) |11111111|11111111|10010000| [24] ffff90 [24]
(180) |11111111|11111111|10010001| [24] ffff91 [24]
(181) |11111111|11111111|10010010| [24] ffff92 [24]
(182) |11111111|11111111|10010011| [24] ffff93 [24]
(183) |11111111|11111111|10010100| [24] ffff94 [24]
(184) |11111111|11111111|10010101| [24] ffff95 [24]
(185) |11111111|11111111|10010110| [24] ffff96 [24]
(186) |11111111|11111111|10010111| [24] ffff97 [24]
(187) |11111111|11111111|10011000| [24] ffff98 [24]
(188) |11111111|11111111|10011001| [24] ffff99 [24]
(189) |11111111|11111111|10011010| [24] ffff9a [24]
(190) |11111111|11111111|10011011| [24] ffff9b [24]
(191) |11111111|11111111|10011100| [24] ffff9c [24]
(192) |11111111|11111111|10011101| [24] ffff9d [24]
(193) |11111111|11111111|10011110| [24] ffff9e [24]
(194) |11111111|11111111|10011111| [24] ffff9f [24]
(195) |11111111|11111111|10100000| [24] ffffa0 [24]
(196) |11111111|11111111|10100001| [24] ffffa1 [24]
(197) |11111111|11111111|10100010| [24] ffffa2 [24]
(198) |11111111|11111111|10100011| [24] ffffa3 [24]
(199) |11111111|11111111|10100100| [24] ffffa4 [24]
(200) |11111111|11111111|10100101| [24] ffffa5 [24]
(201) |11111111|11111111|10100110| [24] ffffa6 [24]
(202) |11111111|11111111|10100111| [24] ffffa7 [24]
(203) |11111111|11111111|10101000| [24] ffffa8 [24]
(204) |11111111|11111111|10101001| [24] ffffa9 [24]
(205) |11111111|11111111|10101010| [24] ffffaa [24]
(206) |11111111|11111111|10101011| [24] ffffab [24]
(207) |11111111|11111111|10101100| [24] ffffac [24]
(208) |11111111|11111111|10101101| [24] ffffad [24]
(209) |11111111|11111111|10101110| [24] ffffae [24]
(210) |11111111|11111111|10101111| [24] ffffaf [24]
(211) |11111111|11111111|10110000| [24] ffffb0 [24]
(212) |11111111|11111111|10110001| [24] ffffb1 [24]
(213) |11111111|11111111|10110010| [24] ffffb2 [24]
(214) |11111111|11111111|10110011| [24] ffffb3 [24]
(215) |11111111|11111111|10110100| [24] ffffb4 [24]
(216) |11111111|11111111|10110101| [24] ffffb5 [24]
(217) |11111111|11111111|10110110| [24] ffffb6 [24]
(218) |11111111|11111111|10110111| [24] ffffb7 [24]
(219) |11111111|11111111|10111000| [24] ffffb8 [24]
(220) |11111111|11111111|10111001| [24] ffffb9 [24]
(221) |11111111|11111111|10111010| [24] ffffba [24]
(222) |11111111|11111111|10111011| [24] ffffbb [24]
(223) |11111111|11111111|10111100| [24] ffffbc [24]
(224) |11111111|11111111|10111101| [24] ffffbd [24]
(225) |11111111|11111111|10111110| [24] ffffbe [24]
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(226) |11111111|11111111|10111111| [24] ffffbf [24]
(227) |11111111|11111111|11000000| [24] ffffc0 [24]
(228) |11111111|11111111|11000001| [24] ffffc1 [24]
(229) |11111111|11111111|11000010| [24] ffffc2 [24]
(230) |11111111|11111111|11000011| [24] ffffc3 [24]
(231) |11111111|11111111|11000100| [24] ffffc4 [24]
(232) |11111111|11111111|11000101| [24] ffffc5 [24]
(233) |11111111|11111111|11000110| [24] ffffc6 [24]
(234) |11111111|11111111|11000111| [24] ffffc7 [24]
(235) |11111111|11111111|11001000| [24] ffffc8 [24]
(236) |11111111|11111111|11001001| [24] ffffc9 [24]
(237) |11111111|11111111|11001010| [24] ffffca [24]
(238) |11111111|11111111|11001011| [24] ffffcb [24]
(239) |11111111|11111111|11001100| [24] ffffcc [24]
(240) |11111111|11111111|11001101| [24] ffffcd [24]
(241) |11111111|11111111|11001110| [24] ffffce [24]
(242) |11111111|11111111|11001111| [24] ffffcf [24]
(243) |11111111|11111111|11010000| [24] ffffd0 [24]
(244) |11111111|11111111|11010001| [24] ffffd1 [24]
(245) |11111111|11111111|11010010| [24] ffffd2 [24]
(246) |11111111|11111111|11010011| [24] ffffd3 [24]
(247) |11111111|11111111|11010100| [24] ffffd4 [24]
(248) |11111111|11111111|11010101| [24] ffffd5 [24]
(249) |11111111|11111111|11010110| [24] ffffd6 [24]
(250) |11111111|11111111|11010111| [24] ffffd7 [24]
(251) |11111111|11111111|11011000| [24] ffffd8 [24]
(252) |11111111|11111111|11011001| [24] ffffd9 [24]
(253) |11111111|11111111|11011010| [24] ffffda [24]
(254) |11111111|11111111|11011011| [24] ffffdb [24]
(255) |11111111|11111111|11011100| [24] ffffdc [24]
EOS (256) |11111111|11111111|11011101| [24] ffffdd [24]
Appendix E. Examples
A number of examples are worked through here, for both requests and
responses, and with and without huffman coding.
E.1. Request Decoding Example With Huffman
# Header set to be encoded
:method: GET
:scheme: http
:path: /
:authority: www.foo.com
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# Hexdump of encoded data which will be decoded
02 84 f7 77 78 ff 07 83 ce 31 77 06 81 0f 04 88 | ...wx....1w.....
db 6d 89 8b 5a 44 b7 4f | .m..ZD.O
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '02'
name_index:
encoded: "02"
decoded: 2
value_data_length:
encoded: "84"
decoded: 4
value_data:
is_huffman_encoded: 1
encoded: "f77778ff"
decoded: "GET"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '07'
name_index:
encoded: "07"
decoded: 7
value_data_length:
encoded: "83"
decoded: 3
value_data:
is_huffman_encoded: 1
encoded: "ce3177"
decoded: "http"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '06'
name_index:
encoded: "06"
decoded: 6
value_data_length:
encoded: "81"
decoded: 1
value_data:
is_huffman_encoded: 1
encoded: "0f"
decoded: "/"
LITERAL_INCREMENTAL_OPCODE:
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opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '04'
name_index:
encoded: "04"
decoded: 4
value_data_length:
encoded: "88"
decoded: 8
value_data:
is_huffman_encoded: 1
encoded: "db6d898b5a44b74f"
decoded: "www.foo.com"
# Decoded header set
:authority: www.foo.com
:method: GET
:path: /
:scheme: http
#########################
# Header set to be encoded
:method: GET
:scheme: https
:path: /
:authority: www.bar.com
cache-control: no-cache
# Hexdump of encoded data which will be decoded
03 84 ce 31 74 3f 02 88 db 6d 89 7a 1e 44 b7 4f | ...1t?...m.z.D.O
1d 86 63 65 4a 13 98 ff 83 85 | ..ceJ.....
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '03'
name_index:
encoded: "03"
decoded: 3
value_data_length:
encoded: "84"
decoded: 4
value_data:
is_huffman_encoded: 1
encoded: "ce31743f"
decoded: "https"
Peon & Ruellan Expires April 24, 2014 [Page 35]
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LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '02'
name_index:
encoded: "02"
decoded: 2
value_data_length:
encoded: "88"
decoded: 8
value_data:
is_huffman_encoded: 1
encoded: "db6d897a1e44b74f"
decoded: "www.bar.com"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '1d'
name_index:
encoded: "1d"
decoded: 29
value_data_length:
encoded: "86"
decoded: 6
value_data:
is_huffman_encoded: 1
encoded: "63654a1398ff"
decoded: "no-cache"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '83'
entry_index:
encoded: "83"
decoded: 3
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '85'
entry_index:
encoded: "85"
decoded: 5
# Decoded header set
:authority: www.bar.com
:method: GET
:path: /
:scheme: https
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cache-control: no-cache
#########################
# Header set to be encoded
:method: GET
:scheme: https
:path: /custom-path.css
:authority: www.bar.com
custom-key: custom-value
# Hexdump of encoded data which will be decoded
05 8b 04 eb 08 b7 49 5c 88 e6 44 c2 1f 00 88 4e | ......I\..D....N
b0 8b 74 97 90 fa 7f 89 4e b0 8b 74 97 9a 17 a8 | ..t.....N..t....
ff 82 86 | ...
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '05'
name_index:
encoded: "05"
decoded: 5
value_data_length:
encoded: "8b"
decoded: 11
value_data:
is_huffman_encoded: 1
encoded: "04eb08b7495c88e644c21f"
decoded: "/custom-path.css"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '00'
name_index:
encoded: "00"
decoded: 0
name_data_length:
encoded: "88"
decoded: 8
name_data:
is_huffman_encoded: 1
encoded: "4eb08b749790fa7f"
decoded: "custom-key"
value_data_length:
encoded: "89"
decoded: 9
value_data:
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is_huffman_encoded: 1
encoded: "4eb08b74979a17a8ff"
decoded: "custom-value"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '82'
entry_index:
encoded: "82"
decoded: 2
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '86'
entry_index:
encoded: "86"
decoded: 6
# Decoded header set
:authority: www.bar.com
:method: GET
:path: /custom-path.css
:scheme: https
custom-key: custom-value
#########################
E.2. Request Decoding Example Without Huffman
# Header set to be encoded
:method: GET
:scheme: http
:path: /
:authority: www.foo.com
# Hexdump of encoded data which will be decoded
02 03 47 45 54 07 04 68 74 74 70 06 01 2f 04 0b | ..GET..http../..
77 77 77 2e 66 6f 6f 2e 63 6f 6d | www.foo.com
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '02'
name_index:
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encoded: "02"
decoded: 2
value_data_length:
encoded: "03"
decoded: 3
value_data:
is_huffman_encoded: 0
encoded: "474554"
decoded: "GET"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '07'
name_index:
encoded: "07"
decoded: 7
value_data_length:
encoded: "04"
decoded: 4
value_data:
is_huffman_encoded: 0
encoded: "68747470"
decoded: "http"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '06'
name_index:
encoded: "06"
decoded: 6
value_data_length:
encoded: "01"
decoded: 1
value_data:
is_huffman_encoded: 0
encoded: "2f"
decoded: "/"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '04'
name_index:
encoded: "04"
decoded: 4
value_data_length:
encoded: "0b"
decoded: 11
value_data:
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is_huffman_encoded: 0
encoded: "7777772e666f6f2e636f6d"
decoded: "www.foo.com"
# Decoded header set
:authority: www.foo.com
:method: GET
:path: /
:scheme: http
#########################
# Header set to be encoded
:method: GET
:scheme: https
:path: /
:authority: www.bar.com
cache-control: no-cache
# Hexdump of encoded data which will be decoded
03 05 68 74 74 70 73 02 0b 77 77 77 2e 62 61 72 | ..https..www.bar
2e 63 6f 6d 1d 08 6e 6f 2d 63 61 63 68 65 83 85 | .com..no-cache..
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '03'
name_index:
encoded: "03"
decoded: 3
value_data_length:
encoded: "05"
decoded: 5
value_data:
is_huffman_encoded: 0
encoded: "6874747073"
decoded: "https"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '02'
name_index:
encoded: "02"
decoded: 2
value_data_length:
encoded: "0b"
decoded: 11
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value_data:
is_huffman_encoded: 0
encoded: "7777772e6261722e636f6d"
decoded: "www.bar.com"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '1d'
name_index:
encoded: "1d"
decoded: 29
value_data_length:
encoded: "08"
decoded: 8
value_data:
is_huffman_encoded: 0
encoded: "6e6f2d6361636865"
decoded: "no-cache"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '83'
entry_index:
encoded: "83"
decoded: 3
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '85'
entry_index:
encoded: "85"
decoded: 5
# Decoded header set
:authority: www.bar.com
:method: GET
:path: /
:scheme: https
cache-control: no-cache
#########################
# Header set to be encoded
:method: GET
:scheme: https
:path: /custom-path.css
:authority: www.bar.com
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custom-key: custom-value
# Hexdump of encoded data which will be decoded
05 10 2f 63 75 73 74 6f 6d 2d 70 61 74 68 2e 63 | ../custom-path.c
73 73 00 0a 63 75 73 74 6f 6d 2d 6b 65 79 0c 63 | ss..custom-key.c
75 73 74 6f 6d 2d 76 61 6c 75 65 82 86 | ustom-value..
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '05'
name_index:
encoded: "05"
decoded: 5
value_data_length:
encoded: "10"
decoded: 16
value_data:
is_huffman_encoded: 0
encoded: "2f637573746f6d2d706174682e637373"
decoded: "/custom-path.css"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '00'
name_index:
encoded: "00"
decoded: 0
name_data_length:
encoded: "0a"
decoded: 10
name_data:
is_huffman_encoded: 0
encoded: "637573746f6d2d6b6579"
decoded: "custom-key"
value_data_length:
encoded: "0c"
decoded: 12
value_data:
is_huffman_encoded: 0
encoded: "637573746f6d2d76616c7565"
decoded: "custom-value"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '82'
entry_index:
encoded: "82"
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decoded: 2
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '86'
entry_index:
encoded: "86"
decoded: 6
# Decoded header set
:authority: www.bar.com
:method: GET
:path: /custom-path.css
:scheme: https
custom-key: custom-value
#########################
E.3. Response Decoding Example With Huffman
# Header set to be encoded
:status: 302
cache-control: private
date: Mon, 21 OCt 2013 20:13:21 GMT
location: : https://www.bar.com
# Hexdump of encoded data which will be decoded
08 82 40 9f 18 86 c3 1b 39 bf 38 7f 22 92 a2 fb | ..@.....9.8."...
a2 03 20 f2 eb cc 0c 49 00 62 d2 43 4c 82 7a 1d | .. ....I.b.CL.z.
2f 91 68 71 cf 3c 32 6e bd 7e 9e 9e 92 6e 7e 32 | /.hq.<2n.~...n~2
55 7d bf | U}.
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '08'
name_index:
encoded: "08"
decoded: 8
value_data_length:
encoded: "82"
decoded: 2
value_data:
is_huffman_encoded: 1
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encoded: "409f"
decoded: "302"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '18'
name_index:
encoded: "18"
decoded: 24
value_data_length:
encoded: "86"
decoded: 6
value_data:
is_huffman_encoded: 1
encoded: "c31b39bf387f"
decoded: "private"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '22'
name_index:
encoded: "22"
decoded: 34
value_data_length:
encoded: "92"
decoded: 18
value_data:
is_huffman_encoded: 1
encoded: "a2fba20320f2ebcc0c490062d2434c827a1d"
decoded: "Mon, 21 OCt 2013 20:13:21 GMT"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '2f'
name_index:
encoded: "2f"
decoded: 47
value_data_length:
encoded: "91"
decoded: 17
value_data:
is_huffman_encoded: 1
encoded: "6871cf3c326ebd7e9e9e926e7e32557dbf"
decoded: ": https://www.bar.com"
# Decoded header set
:status: 302
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cache-control: private
date: Mon, 21 OCt 2013 20:13:21 GMT
location: : https://www.bar.com
#########################
# Header set to be encoded
:status: 200
cache-control: private
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
content-encoding: gzip
set-cookie: foo=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAALASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ1234 max-age=3600; version=1
# Hexdump of encoded data which will be decoded
04 82 31 1f 03 92 a2 fb a2 03 20 f2 eb cc 0c 49 | ..1....... ....I
00 62 d2 43 4c c2 7a 1d 03 90 e3 9e 78 64 dd 7a | .b.CL.z.....xd.z
fd 3d 3d 24 dc fc 64 aa fb 7f 20 84 e1 fb b3 0f | .==$..d... .....
3d ff ee 02 df 7d fb 36 ed db b7 6e dd bb 76 ed | =....}.6...n..v.
db b7 6e dd bb 76 ed db b7 6e dd bb 76 ed db b7 | ..n..v...n..v...
6e dd bb 76 ed db b7 6e dd bb 76 ed db b7 6e dd | n..v...n..v...n.
bb 76 ed db b7 6e dd bb 76 ed db b7 6e dd bb 76 | .v...n..v...n..v
ed db b7 6e dd bb 7e 3b 69 ec f0 fe 7e 1f d7 f3 | ...n..~;i...~...
d5 fe 7f 7e 5f d7 9f 6f 97 cb bf e9 b7 fb fe bc | ...~_..o........
fb 7c bb fe 9b 7f bf 8f 87 f3 f0 fe bc fc bb 7b | .|.............{
fe 9b 7e 3f d7 9f 6f 97 7f d3 6f f7 f1 fe bb 7e | ..~?..o...o....~
9b 7f bf 8f c7 f9 f0 db 4f 67 f5 e7 db e5 f4 ef | ........Og......
db fd f8 91 a1 3f 1d b4 f6 78 7f 3f 0f eb f9 ea | .....?...x.?....
ff 3f bf 2f eb cf b7 cb e5 df f4 db fd ff 5e 7d | .?./..........^}
be 5d ff 4d bf df c7 c3 f9 f8 7f 5e 7e 5d bd ff | .].M.......^~]..
4d bf 1f eb cf b7 cb bf e9 b7 fb f8 ff 5d bf 4d | M............].M
bf df c7 e3 fc f8 6d a7 b3 fa f3 ed f2 fa 77 ed | ......m.......w.
fe fc 48 d0 9f 8e da 7b 3c 3f 9f 87 f5 fc f5 7f | ..H....{<?......
9f df 97 f5 e7 db e5 f2 ef fa 6d fe ff af 3e df | ..........m...>.
2e ff a6 df ef e3 e1 fc fc 3f af 3f 2e de ff a6 | .........?.?....
df 8f f5 e7 db e5 df f4 db fd fc 7f ae df a6 df | ................
ef e3 f1 fe 7c 36 d3 d9 fd 79 f6 f9 7d 3b f6 ff | ....|6...y..};..
7e 24 68 4f c7 6d 3d 9e 1f cf c3 fa fe 7a bf cf | ~$hO.m=......z..
ef cb fa f3 ed f2 f9 77 fd 36 ff 7f d7 9f 6f 97 | .......w.6....o.
7f d3 6f f7 f1 f0 fe 7e 1f d7 9f 97 6f 7f d3 6f | ..o....~....o..o
c7 fa f3 ed f2 ef fa 6d fe fe 3f d7 6f d3 6f f7 | .......m..?.o.o.
f1 f8 ff 3e 1b 69 ec fe bc fb 7c be 9d fb 7f bf | ...>.i....|.....
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12 34 27 fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f | .4'..?....?....?
cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf | ....?....?....?.
f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 | ...?....?....?..
fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc | ..?....?....?...
ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff | .?....?....?....
3f cf f3 fc ff 3f cf f3 fc ff 3f cf f0 8d 09 0b | ?....?....?.....
5f d2 37 f0 86 c4 4a 23 ef 0e 70 c7 2b 2f bb 61 | _.7...J#..p.+/.a
7f 85 86 88 | ....
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '04'
name_index:
encoded: "04"
decoded: 4
value_data_length:
encoded: "82"
decoded: 2
value_data:
is_huffman_encoded: 1
encoded: "311f"
decoded: "200"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '03'
name_index:
encoded: "03"
decoded: 3
value_data_length:
encoded: "92"
decoded: 18
value_data:
is_huffman_encoded: 1
encoded: "a2fba20320f2ebcc0c490062d2434cc27a1d"
decoded: "Mon, 21 OCt 2013 20:13:22 GMT"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '03'
name_index:
encoded: "03"
decoded: 3
value_data_length:
encoded: "90"
decoded: 16
value_data:
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is_huffman_encoded: 1
encoded: "e39e7864dd7afd3d3d24dcfc64aafb7f"
decoded: "https://www.bar.com"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '20'
name_index:
encoded: "20"
decoded: 32
value_data_length:
encoded: "84"
decoded: 4
value_data:
is_huffman_encoded: 1
encoded: "e1fbb30f"
decoded: "gzip"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '3d'
name_index:
encoded: "3d"
decoded: 61
value_data_length:
encoded: "ffee02"
decoded: 493
value_data:
is_huffman_encoded: 1
encoded: "df7dfb36eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76edd\
bb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddb\
b76eddbb7e3b69ecf0fe7e1fd7f3d5fe7f7e5fd79f6f97cbbfe9b7fbfebcfb7cbbfe9b7\
fbf8f87f3f0febcfcbb7bfe9b7e3fd79f6f977fd36ff7f1febb7e9b7fbf8fc7f9f0db4f\
67f5e7dbe5f4efdbfdf891a13f1db4f6787f3f0febf9eaff3fbf2febcfb7cbe5dff4dbf\
dff5e7dbe5dff4dbfdfc7c3f9f87f5e7e5dbdff4dbf1febcfb7cbbfe9b7fbf8ff5dbf4d\
bfdfc7e3fcf86da7b3faf3edf2fa77edfefc48d09f8eda7b3c3f9f87f5fcf57f9fdf97f\
5e7dbe5f2effa6dfeffaf3edf2effa6dfefe3e1fcfc3faf3f2edeffa6df8ff5e7dbe5df\
f4dbfdfc7faedfa6dfefe3f1fe7c36d3d9fd79f6f97d3bf6ff7e24684fc76d3d9e1fcfc\
3fafe7abfcfefcbfaf3edf2f977fd36ff7fd79f6f977fd36ff7f1f0fe7e1fd79f976f7f\
d36fc7faf3edf2effa6dfefe3fd76fd36ff7f1f8ff3e1b69ecfebcfb7cbe9dfb7fbf123\
427fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcf\
f3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff\
3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff08d090b5fd237f086c44a23ef0e70c7\
2b2fbb617f"
decoded: "foo=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAALASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIU\
AXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQ\
WEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOE\
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IUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJK\
HQWOEIUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234ZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ1234max-age=3600; version=1\
"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '85'
entry_index:
encoded: "85"
decoded: 5
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '86'
entry_index:
encoded: "86"
decoded: 6
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '88'
entry_index:
encoded: "88"
decoded: 8
# Decoded header set
:status: 200
cache-control: private
content-encoding: gzip
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
set-cookie: foo=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAALASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ1234 max-age=3600; version=1
#########################
# Header set to be encoded
:status: 200
cache-control: private
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
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content-encoding: gzip
set-cookie: foo=ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZLASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1234 max-age=3600; version=1
# Hexdump of encoded data which will be decoded
01 ff ee 02 df 7d fb 3f cf f3 fc ff 3f cf f3 fc | .....}.?....?...
ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff | .?....?....?....
3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f | ?....?....?....?
cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf | ....?....?....?.
f3 fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 | ...?....?....?..
fc ff 3f cf f3 fc ff 3f cf f3 fc ff 3f cf f3 fc | ..?....?....?...
ff 3e 3b 69 ec f0 fe 7e 1f d7 f3 d5 fe 7f 7e 5f | .>;i...~......~_
d7 9f 6f 97 cb bf e9 b7 fb fe bc fb 7c bb fe 9b | ..o.........|...
7f bf 8f 87 f3 f0 fe bc fc bb 7b fe 9b 7e 3f d7 | ..........{..~?.
9f 6f 97 7f d3 6f f7 f1 fe bb 7e 9b 7f bf 8f c7 | .o...o....~.....
f9 f0 db 4f 67 f5 e7 db e5 f4 ef db fd f8 91 a1 | ...Og...........
3f 1d b4 f6 78 7f 3f 0f eb f9 ea ff 3f bf 2f eb | ?...x.?.....?./.
cf b7 cb e5 df f4 db fd ff 5e 7d be 5d ff 4d bf | .........^}.].M.
df c7 c3 f9 f8 7f 5e 7e 5d bd ff 4d bf 1f eb cf | ......^~]..M....
b7 cb bf e9 b7 fb f8 ff 5d bf 4d bf df c7 e3 fc | ........].M.....
f8 6d a7 b3 fa f3 ed f2 fa 77 ed fe fc 48 d0 9f | .m.......w...H..
8e da 7b 3c 3f 9f 87 f5 fc f5 7f 9f df 97 f5 e7 | ..{<?...........
db e5 f2 ef fa 6d fe ff af 3e df 2e ff a6 df ef | .....m...>......
e3 e1 fc fc 3f af 3f 2e de ff a6 df 8f f5 e7 db | ....?.?.........
e5 df f4 db fd fc 7f ae df a6 df ef e3 f1 fe 7c | ...............|
36 d3 d9 fd 79 f6 f9 7d 3b f6 ff 7e 24 68 4f c7 | 6...y..};..~$hO.
6d 3d 9e 1f cf c3 fa fe 7a bf cf ef cb fa f3 ed | m=......z.......
f2 f9 77 fd 36 ff 7f d7 9f 6f 97 7f d3 6f f7 f1 | ..w.6....o...o..
f0 fe 7e 1f d7 9f 97 6f 7f d3 6f c7 fa f3 ed f2 | ..~....o..o.....
ef fa 6d fe fe 3f d7 6f d3 6f f7 f1 f8 ff 3e 1b | ..m..?.o.o....>.
69 ec fe bc fb 7c be 9d fb 7f bf 12 34 27 6e dd | i....|......4'n.
bb 76 ed db b7 6e dd bb 76 ed db b7 6e dd bb 76 | .v...n..v...n..v
ed db b7 6e dd bb 76 ed db b7 6e dd bb 76 ed db | ...n..v...n..v..
b7 6e dd bb 76 ed db b7 6e dd bb 76 ed db b7 6e | .n..v...n..v...n
dd bb 76 ed db b7 6e dd bb 76 ed db b4 8d 09 0b | ..v...n..v......
5f d2 37 f0 86 c4 4a 23 ef 0e 70 c7 2b 2f bb 61 | _.7...J#..p.+/.a
7f 81 | ..
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '01'
name_index:
Peon & Ruellan Expires April 24, 2014 [Page 49]
Internet-Draft HPACK October 2013
encoded: "01"
decoded: 1
value_data_length:
encoded: "ffee02"
decoded: 493
value_data:
is_huffman_encoded: 1
encoded: "df7dfb3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3f\
cff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fc\
ff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3fcff3e3b69ecf\
0fe7e1fd7f3d5fe7f7e5fd79f6f97cbbfe9b7fbfebcfb7cbbfe9b7fbf8f87f3f0febcfc\
bb7bfe9b7e3fd79f6f977fd36ff7f1febb7e9b7fbf8fc7f9f0db4f67f5e7dbe5f4efdbf\
df891a13f1db4f6787f3f0febf9eaff3fbf2febcfb7cbe5dff4dbfdff5e7dbe5dff4dbf\
dfc7c3f9f87f5e7e5dbdff4dbf1febcfb7cbbfe9b7fbf8ff5dbf4dbfdfc7e3fcf86da7b\
3faf3edf2fa77edfefc48d09f8eda7b3c3f9f87f5fcf57f9fdf97f5e7dbe5f2effa6dfe\
ffaf3edf2effa6dfefe3e1fcfc3faf3f2edeffa6df8ff5e7dbe5dff4dbfdfc7faedfa6d\
fefe3f1fe7c36d3d9fd79f6f97d3bf6ff7e24684fc76d3d9e1fcfc3fafe7abfcfefcbfa\
f3edf2f977fd36ff7fd79f6f977fd36ff7f1f0fe7e1fd79f976f7fd36fc7faf3edf2eff\
a6dfefe3fd76fd36ff7f1f8ff3e1b69ecfebcfb7cbe9dfb7fbf1234276eddbb76eddbb7\
6eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76eddbb76\
eddbb76eddbb76eddbb76eddbb76eddbb76eddbb48d090b5fd237f086c44a23ef0e70c7\
2b2fbb617f"
decoded: "foo=ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZLASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIU\
AXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQ\
WEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOE\
IUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJK\
HQWOEIUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234AAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1234max-age=3600; version=1\
"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '81'
entry_index:
encoded: "81"
decoded: 1
# Decoded header set
:status: 200
cache-control: private
content-encoding: gzip
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
set-cookie: foo=ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZLASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
Peon & Ruellan Expires April 24, 2014 [Page 50]
Internet-Draft HPACK October 2013
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1234 max-age=3600; version=1
#########################
E.4. Response Decoding Example Without Huffman
# Header set to be encoded
:status: 302
cache-control: private
date: Mon, 21 OCt 2013 20:13:21 GMT
location: : https://www.bar.com
# Hexdump of encoded data which will be decoded
08 03 33 30 32 18 07 70 72 69 76 61 74 65 22 1d | ..302..private".
4d 6f 6e 2c 20 32 31 20 4f 43 74 20 32 30 31 33 | Mon, 21 OCt 2013
20 32 30 3a 31 33 3a 32 31 20 47 4d 54 2f 15 3a | 20:13:21 GMT/.:
20 68 74 74 70 73 3a 2f 2f 77 77 77 2e 62 61 72 | https://www.bar
2e 63 6f 6d | .com
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '08'
name_index:
encoded: "08"
decoded: 8
value_data_length:
encoded: "03"
decoded: 3
value_data:
is_huffman_encoded: 0
encoded: "333032"
decoded: "302"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '18'
name_index:
encoded: "18"
decoded: 24
value_data_length:
encoded: "07"
Peon & Ruellan Expires April 24, 2014 [Page 51]
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decoded: 7
value_data:
is_huffman_encoded: 0
encoded: "70726976617465"
decoded: "private"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '22'
name_index:
encoded: "22"
decoded: 34
value_data_length:
encoded: "1d"
decoded: 29
value_data:
is_huffman_encoded: 0
encoded: "4d6f6e2c203231204f437420323031332032303a31333a3231204\
74d54"
decoded: "Mon, 21 OCt 2013 20:13:21 GMT"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '2f'
name_index:
encoded: "2f"
decoded: 47
value_data_length:
encoded: "15"
decoded: 21
value_data:
is_huffman_encoded: 0
encoded: "3a2068747470733a2f2f7777772e6261722e636f6d"
decoded: ": https://www.bar.com"
# Decoded header set
:status: 302
cache-control: private
date: Mon, 21 OCt 2013 20:13:21 GMT
location: : https://www.bar.com
#########################
# Header set to be encoded
:status: 200
cache-control: private
date: Mon, 21 OCt 2013 20:13:22 GMT
Peon & Ruellan Expires April 24, 2014 [Page 52]
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location: https://www.bar.com
content-encoding: gzip
set-cookie: foo=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAALASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ1234 max-age=3600; version=1
# Hexdump of encoded data which will be decoded
04 03 32 30 30 03 1d 4d 6f 6e 2c 20 32 31 20 4f | ..200..Mon, 21 O
43 74 20 32 30 31 33 20 32 30 3a 31 33 3a 32 32 | Ct 2013 20:13:22
20 47 4d 54 03 13 68 74 74 70 73 3a 2f 2f 77 77 | GMT..https://ww
77 2e 62 61 72 2e 63 6f 6d 20 04 67 7a 69 70 3d | w.bar.com .gzip=
7f e1 02 66 6f 6f 3d 41 41 41 41 41 41 41 41 41 | ...foo=AAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 4c | AAAAAAAAAAAAAAAL
41 53 44 4a 4b 48 51 4b 42 5a 58 4f 51 57 45 4f | ASDJKHQKBZXOQWEO
50 49 55 41 58 51 57 45 4f 49 55 41 58 4c 4a 4b | PIUAXQWEOIUAXLJK
48 51 57 4f 45 49 55 41 4c 51 57 45 4f 49 55 41 | HQWOEIUALQWEOIUA
58 4c 51 45 55 41 58 4c 4c 4b 4a 41 53 44 51 57 | XLQEUAXLLKJASDQW
45 4f 55 49 41 58 4e 31 32 33 34 4c 41 53 44 4a | EOUIAXN1234LASDJ
4b 48 51 4b 42 5a 58 4f 51 57 45 4f 50 49 55 41 | KHQKBZXOQWEOPIUA
58 51 57 45 4f 49 55 41 58 4c 4a 4b 48 51 57 4f | XQWEOIUAXLJKHQWO
45 49 55 41 4c 51 57 45 4f 49 55 41 58 4c 51 45 | EIUALQWEOIUAXLQE
55 41 58 4c 4c 4b 4a 41 53 44 51 57 45 4f 55 49 | UAXLLKJASDQWEOUI
41 58 4e 31 32 33 34 4c 41 53 44 4a 4b 48 51 4b | AXN1234LASDJKHQK
42 5a 58 4f 51 57 45 4f 50 49 55 41 58 51 57 45 | BZXOQWEOPIUAXQWE
4f 49 55 41 58 4c 4a 4b 48 51 57 4f 45 49 55 41 | OIUAXLJKHQWOEIUA
4c 51 57 45 4f 49 55 41 58 4c 51 45 55 41 58 4c | LQWEOIUAXLQEUAXL
4c 4b 4a 41 53 44 51 57 45 4f 55 49 41 58 4e 31 | LKJASDQWEOUIAXN1
32 33 34 4c 41 53 44 4a 4b 48 51 4b 42 5a 58 4f | 234LASDJKHQKBZXO
51 57 45 4f 50 49 55 41 58 51 57 45 4f 49 55 41 | QWEOPIUAXQWEOIUA
58 4c 4a 4b 48 51 57 4f 45 49 55 41 4c 51 57 45 | XLJKHQWOEIUALQWE
4f 49 55 41 58 4c 51 45 55 41 58 4c 4c 4b 4a 41 | OIUAXLQEUAXLLKJA
53 44 51 57 45 4f 55 49 41 58 4e 31 32 33 34 5a | SDQWEOUIAXN1234Z
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 31 32 33 34 20 6d 61 78 2d | ZZZZZZZ1234 max-
61 67 65 3d 33 36 30 30 3b 20 76 65 72 73 69 6f | age=3600; versio
6e 3d 31 85 86 88 | n=1...
# Decoded opcodes
Peon & Ruellan Expires April 24, 2014 [Page 53]
Internet-Draft HPACK October 2013
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '04'
name_index:
encoded: "04"
decoded: 4
value_data_length:
encoded: "03"
decoded: 3
value_data:
is_huffman_encoded: 0
encoded: "323030"
decoded: "200"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '03'
name_index:
encoded: "03"
decoded: 3
value_data_length:
encoded: "1d"
decoded: 29
value_data:
is_huffman_encoded: 0
encoded: "4d6f6e2c203231204f437420323031332032303a31333a3232204\
74d54"
decoded: "Mon, 21 OCt 2013 20:13:22 GMT"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '03'
name_index:
encoded: "03"
decoded: 3
value_data_length:
encoded: "13"
decoded: 19
value_data:
is_huffman_encoded: 0
encoded: "68747470733a2f2f7777772e6261722e636f6d"
decoded: "https://www.bar.com"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '20'
name_index:
encoded: "20"
Peon & Ruellan Expires April 24, 2014 [Page 54]
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decoded: 32
value_data_length:
encoded: "04"
decoded: 4
value_data:
is_huffman_encoded: 0
encoded: "677a6970"
decoded: "gzip"
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '3d'
name_index:
encoded: "3d"
decoded: 61
value_data_length:
encoded: "7fe102"
decoded: 480
value_data:
is_huffman_encoded: 0
encoded: "666f6f3d414141414141414141414141414141414141414141414\
14141414141414141414141414141414141414141414141414141414141414141414141\
41414141414141414141414141414c4153444a4b48514b425a584f5157454f504955415\
85157454f495541584c4a4b4851574f454955414c5157454f495541584c51455541584c\
4c4b4a4153445157454f554941584e313233344c4153444a4b48514b425a584f5157454\
f50495541585157454f495541584c4a4b4851574f454955414c5157454f495541584c51\
455541584c4c4b4a4153445157454f554941584e313233344c4153444a4b48514b425a5\
84f5157454f50495541585157454f495541584c4a4b4851574f454955414c5157454f49\
5541584c51455541584c4c4b4a4153445157454f554941584e313233344c4153444a4b4\
8514b425a584f5157454f50495541585157454f495541584c4a4b4851574f454955414c\
5157454f495541584c51455541584c4c4b4a4153445157454f554941584e313233345a5\
a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a\
5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a3\
1323334206d61782d6167653d333630303b2076657273696f6e3d31"
decoded: "foo=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAALASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIU\
AXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQ\
WEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOE\
IUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJK\
HQWOEIUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234ZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ1234max-age=3600; version=1\
"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '85'
entry_index:
encoded: "85"
Peon & Ruellan Expires April 24, 2014 [Page 55]
Internet-Draft HPACK October 2013
decoded: 5
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '86'
entry_index:
encoded: "86"
decoded: 6
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '88'
entry_index:
encoded: "88"
decoded: 8
# Decoded header set
:status: 200
cache-control: private
content-encoding: gzip
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
set-cookie: foo=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAALASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ1234 max-age=3600; version=1
#########################
# Header set to be encoded
:status: 200
cache-control: private
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
content-encoding: gzip
set-cookie: foo=ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZLASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1234 max-age=3600; version=1
# Hexdump of encoded data which will be decoded
Peon & Ruellan Expires April 24, 2014 [Page 56]
Internet-Draft HPACK October 2013
01 7f e1 02 66 6f 6f 3d 5a 5a 5a 5a 5a 5a 5a 5a | ....foo=ZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a | ZZZZZZZZZZZZZZZZ
4c 41 53 44 4a 4b 48 51 4b 42 5a 58 4f 51 57 45 | LASDJKHQKBZXOQWE
4f 50 49 55 41 58 51 57 45 4f 49 55 41 58 4c 4a | OPIUAXQWEOIUAXLJ
4b 48 51 57 4f 45 49 55 41 4c 51 57 45 4f 49 55 | KHQWOEIUALQWEOIU
41 58 4c 51 45 55 41 58 4c 4c 4b 4a 41 53 44 51 | AXLQEUAXLLKJASDQ
57 45 4f 55 49 41 58 4e 31 32 33 34 4c 41 53 44 | WEOUIAXN1234LASD
4a 4b 48 51 4b 42 5a 58 4f 51 57 45 4f 50 49 55 | JKHQKBZXOQWEOPIU
41 58 51 57 45 4f 49 55 41 58 4c 4a 4b 48 51 57 | AXQWEOIUAXLJKHQW
4f 45 49 55 41 4c 51 57 45 4f 49 55 41 58 4c 51 | OEIUALQWEOIUAXLQ
45 55 41 58 4c 4c 4b 4a 41 53 44 51 57 45 4f 55 | EUAXLLKJASDQWEOU
49 41 58 4e 31 32 33 34 4c 41 53 44 4a 4b 48 51 | IAXN1234LASDJKHQ
4b 42 5a 58 4f 51 57 45 4f 50 49 55 41 58 51 57 | KBZXOQWEOPIUAXQW
45 4f 49 55 41 58 4c 4a 4b 48 51 57 4f 45 49 55 | EOIUAXLJKHQWOEIU
41 4c 51 57 45 4f 49 55 41 58 4c 51 45 55 41 58 | ALQWEOIUAXLQEUAX
4c 4c 4b 4a 41 53 44 51 57 45 4f 55 49 41 58 4e | LLKJASDQWEOUIAXN
31 32 33 34 4c 41 53 44 4a 4b 48 51 4b 42 5a 58 | 1234LASDJKHQKBZX
4f 51 57 45 4f 50 49 55 41 58 51 57 45 4f 49 55 | OQWEOPIUAXQWEOIU
41 58 4c 4a 4b 48 51 57 4f 45 49 55 41 4c 51 57 | AXLJKHQWOEIUALQW
45 4f 49 55 41 58 4c 51 45 55 41 58 4c 4c 4b 4a | EOIUAXLQEUAXLLKJ
41 53 44 51 57 45 4f 55 49 41 58 4e 31 32 33 34 | ASDQWEOUIAXN1234
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 | AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41 31 32 33 34 20 6d 61 78 | AAAAAAAA1234 max
2d 61 67 65 3d 33 36 30 30 3b 20 76 65 72 73 69 | -age=3600; versi
6f 6e 3d 31 81 | on=1.
# Decoded opcodes
LITERAL_INCREMENTAL_OPCODE:
opcodeLengthInBits: 2
discoveredFromPeekingAtByte: '01'
name_index:
encoded: "01"
decoded: 1
value_data_length:
encoded: "7fe102"
decoded: 480
value_data:
is_huffman_encoded: 0
encoded: "666f6f3d5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5\
a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a\
5a5a5a5a5a5a5a5a5a5a5a5a5a5a4c4153444a4b48514b425a584f5157454f504955415\
85157454f495541584c4a4b4851574f454955414c5157454f495541584c51455541584c\
Peon & Ruellan Expires April 24, 2014 [Page 57]
Internet-Draft HPACK October 2013
4c4b4a4153445157454f554941584e313233344c4153444a4b48514b425a584f5157454\
f50495541585157454f495541584c4a4b4851574f454955414c5157454f495541584c51\
455541584c4c4b4a4153445157454f554941584e313233344c4153444a4b48514b425a5\
84f5157454f50495541585157454f495541584c4a4b4851574f454955414c5157454f49\
5541584c51455541584c4c4b4a4153445157454f554941584e313233344c4153444a4b4\
8514b425a584f5157454f50495541585157454f495541584c4a4b4851574f454955414c\
5157454f495541584c51455541584c4c4b4a4153445157454f554941584e31323334414\
14141414141414141414141414141414141414141414141414141414141414141414141\
41414141414141414141414141414141414141414141414141414141414141414141413\
1323334206d61782d6167653d333630303b2076657273696f6e3d31"
decoded: "foo=ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZZZZZZZLASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIU\
AXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQ\
WEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOE\
IUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJK\
HQWOEIUALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234AAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1234max-age=3600; version=1\
"
INDEX_OPCODE:
opcodeLengthInBits: 1
discoveredFromPeekingAtByte: '81'
entry_index:
encoded: "81"
decoded: 1
# Decoded header set
:status: 200
cache-control: private
content-encoding: gzip
date: Mon, 21 OCt 2013 20:13:22 GMT
location: https://www.bar.com
set-cookie: foo=ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ\
ZZZZZZZZZZZZZZZZZLASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUAXLQEU\
AXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQWEOIUA\
XLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEIUALQW\
EOIUAXLQEUAXLLKJASDQWEOUIAXN1234LASDJKHQKBZXOQWEOPIUAXQWEOIUAXLJKHQWOEI\
UALQWEOIUAXLQEUAXLLKJASDQWEOUIAXN1234AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1234 max-age=3600; version=1
#########################
Peon & Ruellan Expires April 24, 2014 [Page 58]
Internet-Draft HPACK October 2013
Authors' Addresses
Roberto Peon
Google, Inc
EMail: fenix@google.com
Herve Ruellan
Canon CRF
EMail: herve.ruellan@crf.canon.fr
Peon & Ruellan Expires April 24, 2014 [Page 59]