[tor-dev] Opt-in model for flash proxy

[David Fifield]

Alexandre recently finished up work adding an opt-in option for flash
proxies. Now, clicking on the badge will bring up this page with yes/no
buttons:

http://crypto.stanford.edu/flashproxy/options.html

The default model is still opt-out, though this may change in the
future. If you want to make the badge on your site opt-in-only, add the
cookierequired query parameter to your iframe, and encourage your
visitors to visit the options page. The options work by setting a
cookie.

<iframe src="//crypto.stanford.edu/flashproxy/embed.html?cookierequired" width="80" height="15" frameborder="0" scrolling="no"></iframe>

To summarize, here is what happens if you use cookierequired or not. The
only difference is when the user hasn't set a cookie at all.

Without cookierequired:
				no cookie	cookie=no	cookie=yes
	Will I be a proxy?	yes		no		yes
With cookierequired:
				no cookie	cookie=no	cookie=yes
	Will I be a proxy?	no		no		yes

If we switch to opt-in by default in the future, we'll ignore the
cookierequired parameter and always use the no/no/yes part of the table.
It will also help us switch to opt-in-only if we can get lots of people
to opt in in advance.

David Fifield