BBC accuses BT of throttling iPlayer links

The BBC has accused BT of limiting the speed at which some of its subscribers can access its iPlayer service.

The broadcaster and internet service providers (ISPs) have clashed in the past over the iPlayer and the additional internet traffic it generates.

The on-demand service works at three different speeds, 500Kbits/sec, 700Kbits/sec and 1.5Mbits/sec, depending on the user's broadband connection. High-definition programmes require a connection speed of at least 3.2Mbits/sec.

The BBC said it recently heard from BT customers who said they were experiencing very poor-quality video streams in the evenings.

A representative for the BBC said: “While customers listening to audio and lower-quality video streams would be unaffected, we are concerned that at peak times some customers' higher-quality video streams may be interrupted by buffering before falling back to a lower-quality version.

"This would suggest that traffic identified as BBC iPlayer traffic is being throttled back, thereby limiting the bandwidth used up by the service on slower connections."

However, BT denied it was targeting iPlayer users. The ISP said it managed traffic bandwidth "in order to optimise the experience for all customers". Customers on its BT Option 1 plan have their speed for streaming video cut back from 8Mbits/sec to under 1Mbits/sec between 5pm and midnight.

A representative for the company said: “At present we don't cap speed down to 700Kbits/sec on iPlayer. We believe there is a real issue that content owners such as the BBC need to address and we are currently in discussions with the BBC executive to ensure that our customers get the best possible experience in the future.”

Ofcom, which last year brought in a voluntary code of practice asking ISPs to provide clear information about speeds when users sign up, said it was aware of the issues and was investigating.