FCC Asks if Comcast Slows Rivals' VoIP Traffic
Looks like Comcast’s new network management plan is drawing the ire of competing Voice over IP providers and the scrutiny of federal regulators. The plan, which is detailed here, basically slows bandwidth hogs broadband speeds during times of congestion at a particular node. Apparently, it also has the unfortunate side effect of lowering voice quality for VoIP services — including those offered by Comcast’s competitors. More interestingly, Comcast advertises that its own digital calling service (a variation on VoIP) is unaffected by such network slowdowns, and the FCC wants to know why. In a letter filed on Sunday, the FCC asks Comcast:
We request that Comcast explain why it omitted from its filings with the Commission the distinct effects that Comcast’s new network management technique has on Comcast’s VoIP offering versus those of its competitors. We also ask that you provide a detailed justification for Comcast’s disparate treatment of its own VoIP service as compared to that offered by other VoIP providers on its network. In particular please explain how Comcast Digital Voice is “facilitites based,” how Comcast Digital Voice uses Comcast broadband facilities, and, in particular, whether (and if so, how) Comcast Digital Voice affects network congestion in a different manner than other VoIP services.
Comcast has until Jan. 30 to respond to the FCC, and a spokeswoman said the cable provider was reviewing the letter. In an emailed statement she said, “We have fully complied with the FCC’s order regarding our congestion management practices.”
My guess from talking to other cable voice providers is that Comcast will make a distinction between VoIP traffic that travels across the public Internet and its own digital voice service, which Comcast tries to route across its own broadband pipes. Looks like Comcast will have to rev up its marketing machine before the new Commission to explain how this version of network management is better than its previous P2P throttling efforts. The Commission wasn’t impressed last time; will Comcast’s arguments pass muster with the incoming regulatory team?
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There is no measurable effect, so far. No VOIP users have complained as far as I can see.
A few Vonage users on Comcast appear to have commented here and there; but, Vonage often sucks.
I’ve used Skype for years on Comcast without a whisper of a problem. I video conference with a friend the other side of the country several times a week and he uses Skype or Google Voice with no problems. His Vonage drops dead every 6-8 weeks. He’s also on Comcast.
So far – and I stress this is short term peering around the Web – I see nothing but a fishing trip.
I’ve recently had problems with both Vonage (after 4 years with no problems) and magicJack over Comcast.
Periodically, bandwidth will drop to near 0, resulting in 20- to 30-second silent times during my calls. I thought it was Vonage’s problem so I tried magicJack — exact same behavior.
Comcast claims it’s “network congestion in my neighborhood”. That seems extremely unlikely to me — not that many neighbors and why would it be so periodic?
Comcast is not you nice guy cable company. the will without hesitation lie to you. they are why net neutrality is a must
I’ve been a Comcast internet customer or over 5 years. I’ve been a Vonage customer for over 3 years. About 6 months ago I upgraded my Comcast service from “residential” to “business internet” (which increased both my upstream and downstream bandwidth). DSLReports.com is currently reporting that I’m getting over 6.5Mbps downstream and over 1.4 Mbps upstream bandwidth. But at this very moment (and for the past 5 days), my Vonage service from this location has been unusable – all that gets through are bits and pieces of my voice with a lot of static.
To test my phone, I connected a different phone at the problematic location. No improvement. To test my Vonage phone number (I have two phone numbers configured on my Vonage box), I tried both lines. No difference, both are bad. To test my Vonage box, I connected it in a different location about 80 miles away (but still through Comcast). At this alternate location there were no issues with voice call quality, even though the Comcast service is the slower residential service and not business internet.
Conclusion: At my primary location, Comcast is definitely doing something that negatively impacts Vonage call quality on at least a portion of their network.
Are you sure the secondary site you tried was slower? I have comcast residential with 18Mbps down and 2mbps up. I’d be interested to know what your bandwidth report was during one of those period of bad vonage quality.
I to have been a Vonage subscriber for around five years now and in the beginning I was using a low bandwidth DSL connection and was used to drop packets and conversation but over the past 15 months I have been on ComCast and have not experienced this packet drop.
I can not say that now because over the past two months I have “sometimes unusable” Vonage service with all the packet drop on the upstream side as I can here the other person but they can not here me. I have spent several hours on my cell phone with Vonage and have made some adjustments such as port forwarding my router to the VOIP router, and most recently I upgraded my Firmware on my WRT54G to the “Open WRT” firm ware which enabled quite a few more option like (QoS) which is a must for the VOIP being on the Internet alot – QoS allows me to make sure a certain amount of bandwidth is available to my Vonage Service even if I am downloading something.
Needless to say my Vonage Service has become pretty troublesome and I have complained to ComCast not sure where that will go.
Conclusion with all the “hacking” I have had to do in order to recover some of my service by no means is it like it use to be and I am convinced my ISP has implemented some sort of traffic management that is causing this recent problem.
Cheers
Most of US Pay a fair dollar for our “High Speed Internet Connection” and ex speck to be able to do more then just bang around on web sites and read e-mail. What is the point of paying for all this bandwidth and not being able to access it, especially with another paid service (VOIP).
It seems clear they want to sell us a service but limit our access to it. One would think there are other regulation being broken here.
We are a new user of Vonage and Comcast both. We have residential Comcast for our ISP and which started in Nov. 08 and Vonage that started a week later. As of beginning of this year we have started to have problems with our VOIP, no amount of tech support has helped reducing the gibberish others hear when they call our number.
At this point, I have no doubt Comcast is tinkering with our service!
My husband and I have been a Vonage customer for four years and Comcast customer for five. Our experience is that within the last two months Comcast is slowing down our service and now our calls break up. Before that our Vonage service was perfect.
Comcast is famous for lowering the quality of the service while keeping prices the same. So customers pay more for less service. I’m sad that they are obviously doing it again.
I have been using Skype since 2004 and in the last 2 to 3 months my skype has gone slow. There is a marked 0.6 to 1.5 seconds delay while talking and sometimes it is annoys people on the other end who think that I am not replying to them quick enough.
This is annoying me and not sure what I can do as I have no other choice for broadband where I live.
-WZ