Comcast Defends Its VoIP Service
Comcast, responding to a recent Federal Communications Commission (FCC) probe into the way the MSO treats VoIP traffic from competitive service providers, claims that its own PacketCable-based voice service is a completely separate offering that does not fall under the technical auspices of a new "protocol agnostic" platform that Comcast deployed at the end of last year to help manage its high-speed Internet (HSI) traffic. (See Comcast Goes 'Protocol Agnostic' Everywhere .)
The FCC's beef was that it saw an "apparent discrepancy" between the disclosures Comcast made about its new bandwidth management system and the MSO's FAQ posted on the Comcast.net Website. The FCC asked why Comcast omitted from its earlier filings "the distinct effects that Comcast's new network management technique has on Comcast's VoIP offering versus those of its competitors." (See Comcast Faces VoIP Probe .)
"There is, in fact, no discrepancy," Comcast noted in its five-page response, filed January 30. Comcast says its network management techniques apply only to its high-speed Internet service, not its Comcast Digital Voice, the brand name for the MSO's PacketCable-based phone offering.
Comcast acknowledged that customers who use the MSO's cable modem service to access so-called "over-the-top" VoIP services could suffer bad service under the new bandwidth system. That system aims to treat all IP traffic, including peer-to-peer (P2P) applications, equally, but can slow down some Internet connections temporarily (as long as 10 to 20 minutes) if they are found to be gobbling up an exorbitant amount of network capacity. (See Comcast Details Net Management Moves .)
"This might occur during the limited times when the HSI network in a given area is experiencing congestion, and would in all likelihood affect only a subscriber who has temporarily triggered congestion management thresholds due to his or her own bandwidth consumption," the MSO said.
"Significantly, CDV customers do not need to subscribe to Comcast HSI service, and Comcast does not route those CDV customers' traffic over the public Internet," Comcast added.
Because Comcast views its VoIP service as a completely separate service that does not use the public Internet, the MSO says it wasn't implicated in the Free Press 's original complaint into the MSO's treatment of P2P traffic, Comcast's earlier disclosures detailing the new bandwidth management system, or the subsequent FCC order that called on Comcast to migrate to a new system by the end of 2008. (See FCC Throttles Comcast, FCC Details Comcast Order , and FCC Puts Comcast on the Clock .)
Free Press is expected to respond to this argument once it has a chance to review Comcast's filing. FCC officials were not immediately available for comment.
Update:: Free Press responded Tuesday, holding that Comcast still has some legal and technical questions to account for: "For example, the filing does not state whether the use of Comcast Digital Voice contributes to congestion and triggers throttling. We'll continue to monitor this issue closely," said Free Press policy director Ben Scott.
Other MSOs that have deployed VoIP services using the CableLabs -specified PacketCable architecture, like Comcast, will be watching this proceeding closely.
Cox Communications Inc. , which has also come under fire for its previous treatment of P2P traffic, is testing a new bandwidth management system that, instead of treating all IP apps equally, places them into two categories: "non-time sensitive" and "time sensitive." VoIP, in Cox's estimation, falls into the latter category. (See Study Alleges a Cox Block on P2P Traffic and Cox to Test New Bandwidth Cop .)
— Jeff Baumgartner, Site Editor, Cable Digital News