US legislators are currently considering a move that would allow telecoms providers to charge web sites for better performance. The idea is that sites could pay a levy to get priority over sites that don’t.

The US telcos are in the frame because they own the “last mile” broadband cable connections to most US consumers, and they also own the connection points used by companies to link to the internet. This puts them in a good position to maintain a stranglehold on net traffic.

The legislation under scrutiny is the Communications, Promotion & Enhancement (CPE) Act of 2006, which primarily concerns the roll out of video services via broadband cable modem.

While the legislation appears to cover only web traffic, the idea could be extended to cover other applications. The obvious fear is that voice over IP (VoIP) systems such as Skype, which compete with traditional telephone services, could be denied the high-performance links they need to work effectively.

Not surprisingly, the telcos are lobbying to get the CPE legislation passed, and firms such as Google, Yahoo and Microsoft are lobbying to get it modified. So far the internet firms have been unsuccessful. On 26 April the US House Committee on Energy & Commerce threw out an amendment that would have curbed the telcos’ power to levy such charges. The main bill goes for a further vote this month.

Opponents say the new rules would mean that a user’s experience of a web site would depend on which networks were included in the route between site and user, and whether the site had paid each US telco on that route for a premium service. If the site failed to pay each US ferryman, it would run like treacle in the user’s browser.

Clearly this is different from the situation today, where a site pays one or two service providers for a connection to the net, and does not need to pay again for high-bandwidth delivery to users connecting via a third-party ISP.

Changes could also affect foreign users of US web sites, which might cause US sites to relocate to offshore datacentres. Similarly, British sites might perform poorly in the US unless the US telcos were paid off. Further down the line, there is concern that similar charges would be allowed by other governments.

In essence these arguments are about whether a carrier should be able to charge a premium for traffic from particular IP addresses or using particular TCP/IP protocols. It seems to me that telcos have been doing this sort of thing outside of IP for years. For example, SMS messages are charged at around 10 pence for 160 bytes, which is probably 1,000 times the pence-per-byte charged for phone calls. Telcos don’t do this for IP yet, and long may that situation continue.