Several UK internet service providers (ISPs) have voiced concerns about the effect the BBC's iPlayer will have on their servers.
Tiscali, BT and Carphone Warehouse have said that the iIPlayer - which enables viewers to watch the broadcaster's TV shows online - will exert undue strain on their networks.
The fact that the player is free to use means it is likely to attract a mass audience, which will exacerbate the problem further, the ISPs claim.
Mary Turner, chief executive of Tiscali, said: "The internet was not set up with a view to distributing video. We have been improving our capacity, but the bandwidth we have is not infinite.
"If the iPlayer really takes off, consumers accessing the internet will get very slow service and will call their ISPs to complain."
In anticipation of the huge demand for the BBC's service, Tiscali, Carphone Warehouse and BT have said that they may have to place restrictions on subscribers' use of iPlayer.