Comcast tests new internet bandwidth management

US cable network Comcast has expanded experiments to slow data traffic of "heavy users" across the board during peak hours. These speed limits for individual users with especially high bandwidth consumption are supposed to ensure that the overall network capacity of the broadband provider is not overloaded. According to Comcast manager Mitch Bowling, the connection speed of affected users will still be at the level of a "really good" DSL connection.

In early August of 2007 the US regulatory authority for the telecommunications sector (FCC) served the largest US cable network operator with a cease and desist letter because it impeded a peer-to-peer protocol (P2P). The FCC sees the slowing down of the BitTorrent file sharing protocol as a violation of network neutrality. The authority published its nearly 70 page decision (PDF file) on Wednesday – 20 August 2008. Shortly thereafter, Comcast announced that it would include areas in Pennsylvania, Colorado and Florida in the "network management" experiment, which had previously been limited to Virginia. The company emphasises, however, that it no longer targets individual protocols or applications, but rather total bandwidth use and thus complies with the FCC's conditions.

The throttling procedure will be fully expanded by the end of the year. According to the internet provider, when the system detects jams in the network, it will curb users taking up the most bandwidth "dynamically and in real time". Their data transfers will then be assigned a lower priority for periods of between 10 and 20 minutes. The connection speed remains the same in principle, but data packets sent to and from affected users causing heavy loads will be slowed down. It is still unclear whether "heavy users" will be characterised as such based on uploads, downloads, or a combination of both. At the same time, Comcast is expanding its network and wants to connect some 20 per cent of users over the DOCSIS protocol, which supports transfer rates of up to 100 Mbps.

(Stefan Krempl)

(trk)