Protecting the young people from the harmful content of the Internet is becoming a very important concern. The Internet is growing fast, and there are no or very few control mechanisms over harmful content. Moreover, this content is financed by powerful organizations like pornographic industry. As a result, it is now urging to find how we could protect efficiently our youth.
Nowadays, there are many proprietary filtering software solutions that can efficiently filter the harmful content. But these solutions are expensive and may not be affordable to little educational establishments. They are also mostly designed to filter English-speaking web sites. There is a need for an open source filter because we can afford easily such software and we can adapt it to specific languages and cultural differences between countries.
The POESIA project [1] (Public Opensource Environment for a Safer Internet Access) is an open source Internet content filter funded by the European Commission. This project aims to become the standard filtering solution deployed by educational institutions and for home use. Open extensible architecture enables POESIA software to filter harmful content in several channels (Web, Email, News) and to deploy many kinds of filters: natural language filters (English, Spanish and Italian), image filters, Javascript filters...
The web channel of POESIA needs an HTTP proxy server. That proxy server will be operate on behalf of the browser client and will download the web page before scanning its content by calling filter devices. The Shweby project aims to develop an open source stable HTTP proxy in order to be integrated in POESIA software set. We will try in this paper to describe the requirements of POESIA for an open source HTTP proxy server and to explain how Shweby was designed in order to obey these requirements.
The use of Shweby will not be restrained in POESIA software. The conformance to open Internet standards will enable Shweby to be an open source solution for content adaptation. This will be achieved by implementing the ICAP (Internet Content Adaptation Protocol) in Shweby proxy server. The ICAP protocol [2] is designed by the IETF [3] (Internet Engineering Task Force) in order to allow web proxies to contact ICAP servers and ask them for a content modification of the HTTP requests or the HTTP responses. The content adaptation has many useful applications such as text translation, virus scanning, adapting web pages to small devices (PDAs, Cell phones), advertising banner insertion or removal, etc.
Open source community has welcomed the announcement of Shweby's first releases. There were some interesting feedbacks about these releases. We will try to promote developing, testing and documenting Shweby in the open source community. The future steps in developing Shweby will be testing interoperability with most ICAP servers, even open source or commercial, and to define a framework for developing proxylets.