UK operator T-Mobile is disconnecting its CSD-WAP subscribers from July 9th, suggesting customers might like to switch to GPRS or something a little more 21st century, and disposing of pay-per-minute internet access.
Circuit Switched Data (CSD) was how mobile phones accessed data services in the early days, or at least the technology that allowed them to try. Technically equivalent to a dial-up modem, it allows speeds of up to 9.6Kb/s, ideal for downloading the latest news and reviews from the Mobile Internet.
The first WAP phones only had CSD, and it was the 9.6Kb/sec speed that drove the creation of WAP itself: a desperate attempt to create a usable experience over such slow connections. But even the mono graphics and text-menu content was painfully slow to use, and starkly contrasted with TV advertising in the UK, from Genie Internet, promoting the Mobile Internet.
WAP over CSD was a painful experience, but we were promised that once GPRS came along then the mobile web would rock our worlds. When that failed to happen we were told that 3G would be the revolution; with data at 3G speeds we would all want the web in our hands. That too failed to change the world, so HSDPA came along to make it all happen, and now HSUPA, LTE and WiMAX are all vying to be the next contender. Meanwhile Apple quietly proved that speed isn't everything when it comes to the mobile web
So damning was that original WAP experience that the term is largely verboten in the mobile phone industry, despite the fact that parts of the standard are still in daily use, driving operator portals, delivering content to handsets, and even embedded into Sky's digiboxes for its "red button" services.
CSD is a connection-based technology, just like making a phone call, so connections were charged by the minute rather than by the quantity of data. The last few T-Mobile customers using CSD are paying £2.50 a month for 30 minutes, or are on one of the Freetime tariffs. They're all going to have to migrate to GPRS at least if they want to be able to access the internet on the move: they might even find the experience an improvement. ®