Added a comment

doc/forum/access_restrictions:_for_extranet/comment_1_a0666c3c15661fb0fff70f313cd0d47d._comment

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+[[!comment format=mdwn
+ username="http://smcv.pseudorandom.co.uk/"
+ nickname="smcv"
+ subject="comment 1"
+ date="2012-04-15T20:53:44Z"
+ content="""
+Read/view access and write/edit access are rather different.
+You can limit write access via wiki configuration, and even
+configure it over the web with [[plugins/websetup]].
+
+The only way to limit read access is to restrict access to the
+ entire wiki via `.htaccess` or other web server configuration,
+preferably combined with use of `https`.
+IkiWiki can't limit read access to pages on its own[*],
+because it's a wiki compiler: when a page is viewed, the web
+server serves the compiled HTML without IkiWiki being involved.
+
+The best way to integrate access control into IkiWiki would
+probably be to have a CGI user interface for `.htaccess` or
+equivalent - but you'd still have to be careful, because,
+for instance, if a user can edit public pages, then they
+can insert a `\[[!include]]` directive to make the content
+of a private page public. As a result, the safest way to
+use it is to keep public and private information in
+separate wikis.
+
+[\*] strictly speaking, it *could* via a new plugin, but
+that would defeat many of its advantages
+"""]]