Continuing Silicon.com's 'Ban the Ban' campaign, Felicity Ussher offers a step-by-step guide to the implications of the EU's proposed ban on caching copyrighted materialHow did it all start? The music industry began lobbying the European Parliament (EP) for online copyright laws when the MP3 file format went mainstream last year. MP3 players enable consumers to compress CD-quality music and send it over the Web as tiny email attachments, so they posed a genuine threat to musicians' rights. Artists demanded that the EP make it a crime to copy anything that had not been paid for. After months of discussion, MEP, Roberto Barzanti drafted a proposal, Article 5.1 of which cites Web caching as an example of "incidental copying". It was when MEPs voted to support his proposal, on 11 February, that all the trouble began. So national governments will have to enforce this law? Once MEPs and ministers are agreed on a proposal then, yes, national governments will have to implement it within a few years. However, they can choose the best way of doing this. The next stage is for Mario Monti, European Commissioner in charge of copyright, to redraft Barzanti's report and present it to the EU Council of Ministers. What are the likely consequences if the Bill goes ahead as planned? Member states will probably either ban all Web caching, or just ban the caching of copyrighted material which has not been paid for. If all caching is banned, the Internet will suffer from a major drop in efficiency as so many browsers and servers use caching. If just copyright caching is banned, governments will have to say who is responsible, which could transform the fortunes of ISPs Internet service providers and browser manufacturers. Either way, we can expect a lot of court cases, and smaller Internet services may have to close down, as they would be unlikely to handle that sort of risk. What has this got to do with big business? It's not just ISPs who use Web caching, although services like Freeserve cache around 40 percent of their data. Increasing numbers of corporate servers use caching to transmit data in a steady stream, and this is set to increase. Web browsers and PC hardware use it too. Given that usage is almost ubiquitous, businesses could find their ecommerce strategy seriously affected if caching is banned and the Internet slows down. Why do we need laws on the subject - surely there are technical solutions available? Yes there are. Ecommerce suppliers like InterTrust and music rights organisations like the Performing Music Society have developed payment engines which ensure a payment is made each time a piece of copyrighted music is downloaded. But industry and legislators need to agree who is liable before any of them can be made compulsory. Alternatively, copyright publishers could develop an HTML standard to ensure that copyright material is not cached at all, or at least notify surfers when they are downloading copyright material. What does Article 5.1 say? It states that incidental copies that form a necessary part of data transmission are exempt from online copyright laws - but only if they have been authorised. Surely if everyone is opposed to Web caching, Article 5.1 can simply be removed? It's not that simple. Although the music industry wants Article 5.1 taken out altogether, the Internet industry wants it to stay in, but without the need for authorisation and with the language tightened up. Industry is afraid that if the Article were cut altogether, there would be nothing stopping technologists being made liable for online copying. Where do the EC's draft laws on ecommerce fit in? The music industry is using the ecommerce laws to justify taking out Article 5.1 altogether. It says the ecommerce proposals already specify who is liable for online copyright infringements, and that Article 5.1 duplicates and confuses things. But technologists want greater clarity. Is Barzanti's proposal really likely to become law? It's unlikely to be made law as it stands, because of the violent reaction from industry. Silicon.com, for one, will make sure Mario Monti knows industry's views before submitting his redraft. The big question is how the clause will be reworded, and it could take a long time to work that out. The good news is that the longer the delay, the more stable these technological solutions will be. So it may be that, a few months down the line, the European Parliament simply endorses a range of technologies and insists that one or other of them is used.