[8] [[内容符号化]] [CODE(HTTP)[bzip]] / [CODE(HTTP)[bzip2]] /
[CODE(HTTP)[x-bzip]] / [CODE(HTTP)@en[[[x-bzip2]]]] は HTTP RFC では規定されていませんが、
使用されていることがあるみたいです。
(いずれも同義みたいです。)

[1] [CITE@en[173044 – Support for bzip2 transfer encoding, a la w3m]]
([TIME[2015-08-04 23:46:50 +09:00]] 版)
<https://bugzilla.mozilla.org/show_bug.cgi?id=173044>


[FIG(quote)[
[FIGCAPTION[
[2] [CITE@en[HTTP compression - Wikipedia, the free encyclopedia]]
([TIME[2015-07-27 23:42:37 +09:00]] 版)
<https://en.wikipedia.org/wiki/HTTP_compression#Content-coding_tokens>
]FIGCAPTION]

> bzip2 – compression based on the free bzip2 format, supported by lighttpd'''['''7''']'''

]FIG]


[FIG(quote)[
[FIGCAPTION[
[3] [CITE@en[rockdaboot/mget]]
([TIME[2015-08-04 23:55:03 +09:00]] 版)
<https://github.com/rockdaboot/mget>
]FIGCAPTION]

> 
> Support for bzip2 Content-Encoding / Accept-Encoding compression type

]FIG]


[FIG(quote)[
[FIGCAPTION[
[4] [CITE[Feature configuration file (features.conf)]]
([TIME[2012-10-31 02:59:29 +09:00]] 版)
<http://elinks.or.cz/documentation/html/manual.html-chunked/ch01s07.html#CONFIG-BZIP2>
]FIGCAPTION]

> Bzip2 Decompression (CONFIG_BZIP2)
> This makes ELinks decompress local *.bz2 files. Also, ELinks sends "Accept-Encoding: bzip2" in HTTP requests and decompresses any documents received in that format, but this encoding has not been registered at http://www.iana.org/assignments/http-parameters, so most servers probably won't use it.
> Default: enabled if the library is installed

]FIG]


[5] [CITE[HTTP::Message - search.cpan.org]] ([TIME[2017-09-10 18:28:51 +09:00]]) <http://search.cpan.org/~oalders/HTTP-Message-6.13/lib/HTTP/Message.pm>

[6] >>5 [CODE[Content-Encoding]] として [CODE[bzip2]], [CODE[x-bzip2]] に対応。