== Public Suffix List ==
http://publicsuffix.org/  [[http/cookieの適用範囲]]
{{{
A "public suffix" is one under which Internet users can directly register names. 
}}}
It allows browsers to, for example:
 * Avoid privacy-damaging "supercookies" being set for high-level domain name suffixes
 * Highlight the most important part of a domain name in the user interface
 * Accurately sort history entries by site

2011年9月29日現在のリストからjp関連を抜き出したものは添付ファイルにある。
-- ToshinoriMaeno <<DateTime(2011-09-29T14:06:09+0900)>>

http://publicsuffix.org/list/ [[/LIST FORMAT]]

[[/Formal Algorithm]]  [[/Example]]
== 目的 ==
上位ドメインのクッキー（supercookies)を設定させないように使う。
　リストにないからと言って、安心するのはどうか。

ブラウザのcookieというものが欠陥だという考えもある。
 なぜ上位ドメインに対するcookieを保持させる必要があるのか。

そういうもので、DNSが制約されては、ドメイン売買の商売に差し支えるというのが、ICANNやJPレジストリの考えらしい。
-- ToshinoriMaeno <<DateTime(2011-09-29T16:29:47+0900)>>

{{{
The usefulness of this can be seen if we take the example of cookies.
In the past, browsers used an algorithm which only denied setting wide-ranging cookies
for top-level domains with no dots (e.g. com or org).
However, this did not work for top-level domains where only third-level registrations are allowed (e.g. co.uk).
In these cases, websites could set a cookie for .co.uk which would be passed onto every website registered under co.uk. 
}}}

{{{
Since there was and remains no algorithmic method of finding the highest level
at which a domain may be registered for a particular top-level domain
(the policies differ with each registry),
the only method is to create a list.
This is the aim of the Public Suffix List. 
}}}