On Wed, 31 Mar 2004, Adam Aube wrote:

> However, I have heard of an open source project that does exactly this -
> provide controlled access for public wireless service. The site for the
> project is:

It is not possible do do HTTP proxy authentication in a transparent proxy.

What is possible is to implement a out-of-band authentication scheme, such
as redirecting to a web form where the user can authenticate his IP
address for access to the proxy.