The latest uSwitch survey has used data gathered from 2 million internet speedtests to reveal that broadband ISP download speeds in the UK fall by an average of 35% (6.2Mbps) during periods of peak usage (between 7pm and 9pm), when most people go online. By contrast people who surf between 2am and 3am were found to experience the fastest broadband speeds (average of 9.6Mbps).

The news is by no means a revelation and merely confirms what most people already knew, although the extra detail is welcome. Home broadband has always been a shared "Best Efforts" service that isn't well designed to cater for a large number of users consuming lots of data, at least not without some loss of performance.

This is effectively what makes broadband affordable for the consumer mass market. In short, light (lite) users consume less data and thus offset the heavy ones. However, during peak usage periods, so many people often end up going online that some loss of performance simply becomes unavoidable.


Your mileage could also vary depending upon the ISP (e.g. a more expensive ISP will often set aside extra capacity to handle peak load) and where you live in the country. The data suggests that internet users in the market town of Evesham (Worcestershire) see the worst download speed fall of 69% between peak and off-peak periods (15.5Mbps in the morning to 4.9Mbps in the evening).


It's interesting to note that many consumers sometimes unfairly blame their phone line or ISP for the loss of performance at peak times. Certainly the ISP has a huge responsibility to deliver on its promises and not to over subscribe their networks, although often the most vocal complaints come from those on budget packages. You can't expect the best performance for a pittance.

Similarly the new generation of superfast broadband services, many of which use high capacity fibre optic or coax cable lines, are not immune to this. Technological capability and broadband capacity are two separate sides of the same coin. For example, most connections in South Korea run through 100Mbps+ capable FTTH connections but the average speeds still come in at roughly 14Mbps (Akamai's Q2 State of the Internet Report).