Comic Relief, the bi-annual charity event, is expecting to see more web traffic than ever before in 2005, especially around its Red Nose Day in March. It expects over 150 million hits, making it the single biggest e-commerce event ever - posing a big challenge for its systems.

Martin Gill, Comic Relief head of new media, said that the challenges would take many forms, ranging from "the volume of traffic, to the sheer numbers of people making transactions on the web site, flash-crowds using secure services, and the processing of payments".

To cope with these demands, the charity has entered into partnerships with a number of IT vendors, including Cisco, Empirix, Energis, Macromedia, Oracle, Sun, SkyNet Systems and Zeus Technology, which will provide kit and expertise on the night and in the run-up to the event.

The web site itself must be able to support a large number of users wanting to make payments on it during a very short period. Currently the payment mechanism on the site is a holding page generated by payment processing company WorldPay, but Gill said that a more sophisticated page would be available on the day.

New media and development director Amanda Horton-Mastin said, "The technology [will] enable us to live-authorise donations while all the other exciting online activity is happening. The last Red Nose Day campaign received over £3.7m via new media, and Comic Relief hopes to beat this total in 2005."

This year, Comic Relief will deploy better load-balancing technology to handle the growing traffic. Gill added that the web site would have to manage many different types of sessions and requests, and to earn as much cash as possible the system must avoid downtime.

Horton-Mastin said, "Most people carrying out a transaction get no other return than a good feeling. We have to capitalise on that on the night, not at a later date."

Gill added that the web site is also designed to offer good accessibility so it does not exclude groups such as people with poor eyesight. The design follows the best practice guidelines of European web accessibility legislation.