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Comcast to replace throttling with priority filter

updated 10:20 am EDT, Mon September 22, 2008

Comcast Priority Traffic

Comcast this morning obeyed FCC mandates today by publishing info regarding its replacement for its controversial BitTorrent throttling system. The cable Internet provider now says it will use a Quality of Service (QoS) system that adjusts the priority of data packets for the most frequent users: if a network is congested, a new filter will automatically lower the priority of their data packets until the congestion passes.

The system will in theory add latency to those creating problems on the network for the majority of users but wouldn't discriminate against specific traffic types or cut data off altogether. It should also allow these same users to run their connections uninterrupted at less demanding periods or on networks where congestion isn't an issue.

Comcast anticipates launching the new traffic management method by December and is already set to implement its 250GB monthly transfer cap next month.

The move comes despite a lawsuit against the FCC for its decision to force platform-neutral filtering. Comcast has long argued its previous approach of blocking BitTorrent and certain peer-to-peer networks was "reasonable" despite its damage to legitimate businesses and the company's attempt to hide its practices until an investigation forced it to reveal its policies.

by MacNN Staff



  1. horvatic

    Joined: Dec 1969


    Same c*** different day

    Same c***, different day. COMCAST SUCKS!!!!
    Don't use them!!! They want you to watch TV and video on there cable network. So if you do it online they will slow your internet connection until you
    can't!!!!! They're not an internet provider, they are a cable TV network and that's what they want you to pay for!!! They falsely advertise internet service that is faster than DSL, yet then they slow your connection to dial up speeds!!!!

  1. MadGoat

    Joined: Dec 1969



    If they have a 250GB cap, why throttle at all? Someone should be able to use their entire 250 GB unfiltered until that cap is reached.

    that's just a double whammy, you pay for a service and you can't use it fully.

    Either use one or the other, filter or bandwidth cap. Not both.

  1. Guest

    Joined: Dec 1969


    Actually a good idea

    I think for once Comcast has a decent idea. This prevents the few high usage customers from punishing the average user. If those few people really do NEED guaranteed high bandwidth during peak times then they should cough up the dough for a business grade internet connection.

    Maybe if all these whiners looked into the cost of a guranteed 5Mbps direct internet connection they'd understand why the ISPs are willing to invest the money into these throttling techniques.

    Something else they should do is offer a "Pay as you go" service.

  1. ender

    Joined: Dec 1969


    No problem, except...

    I have no problem with this, with one will they determine "the most frequent users" to know who to throttle? I would never come near the 250 GB/month cap (I'm just a typical email/web user). But suppose I decide to rent an HD movie from iTunes and start watching it before the download is finished. Will I be in danger of triggering some bandwidth limit? Will my movie have to be paused halfway through while waiting for the download to chatch up because my bandwidth was limited by this new system?

    I noticed when I download a few of the free HD TV shows from iTunes last week that about halfway through the download slowed to a crawl. Was this Comcast deciding that I was a heavy user even though I probably download only about 25 GB/month?

  1. UberFu

    Joined: Dec 1969


    All of this...

    coming from Comcast who daily advertises - high-speed internet - with PowerBoost and talks about how it's faster and more reliable than anything else available.

    I agree with MadGoat - they already announced they'd be capping usage to 250GB per month - why do a blanket speed throttle at all?

    This - I assume means that they will be changing the Rate Plans to reflect the new Policies? Because as it stands now - I pay for 8Mb/s DOWN and 1Mb/s UP - with 99% uptime - typically to accomodate maintenance or acts of nature. If that still reads true October 1 and something happens to my throughput Rate - I gaurantee someone high up in Comcast's ranks will hear about it.

  1. dimmer

    Joined: Dec 1969



    If you buy an ISP connection, whatever speeds you requested should be delivered: no caps, no blocking, no filtering. Basic premise of Net Neutrality -- and clearly one which AT&T, ComCast et al. want to do away with at all costs.

    Consider: to implement QoS requires that you examine each packet on the network; aka open it up. How happy would you be if the Post Office decided it was a good idea to open and read your mail before delivery to make sure the "most important" stuff gets through?

  1. Guest

    Joined: Dec 1969


    Some of you don't get it

    If ISPs actually had to guarantee your full bandwidth all the time, you'd never be able to afford it.

    Does Google actually have several GBs of storage for every GMail user? Nope. Could mobile providers actually handle all of its subscribers simultaneously using unlimited nights and weekends? Nope. Could your phone company actually handle everyone making a phone call at the same time? Nope.

    In each of the above examples, usage is determined by the average PER USER cost of doing business. In the case of ISPs, however, computers running P2P software are capable of establishing hundreds, if not thousands, of flow streams. The per user model breaks down.

    P2P software is capable of consuming any additional bandwidth that your ISP tries to provide, with the result that the average user never sees that added capacity. As it stands now, P2P networks consume 98% of the available bandwidth. This ultimately causes random dropped packets, which then causes the TCP/IP protocols to reduce transmission rates and retransmit data. In the end, you actually end up with LESS bandwidth utilization (around 60-70%).

    With flow control in place, you regulate the heaviest network users to minimize the impact of dropped packets. As a result, transmission rates stay high, both for the heavy users and the average users. This benefits EVERYONE, even the P2P users, because there will be much better utilization of the available bandwidth (around 90-95%).

    In effect, flow control can effectively give users a 40-50% increase in bandwidth with no infrastructure additions.

    In response to dimmer, you clearly do not understand the basic premise of Net Neutrality. The original idea was to give equal priority to each "flow". In years past, a single user generated one or only a few flows at a time: an ftp transfer, a telnet connection, etc. But with P2P software, a single user can generate thousands of flows. The average user browsing the web or checking e-mail only generates a few flows and has no hope of competing. They are left with stalled connections and nothing near the speed their ISP hopes to deliver.

    And no, proper flow control does not require any kind of packet inspection. Your ISP knows which packets came from your modem. All it has to do is keep track of how much. If a heavy user exceeds some reasonable threshold AND the capacity of the available bandwidth is being exceeded, limits will be imposed on that user so that Net Neutrality can be guaranteed for the rest of the users.

    Without flow control, software vendors will simply engage in an arms race to see who can create the most flows in order to compete for the available bandwidth. This will ultimately eat up all the available ports on a NAT router and bring your internet connection to a screeching halt.

    Yes, it really is that serious.

  1. bhuot

    Joined: Dec 1969


    not fair

    This reminds me of the old dial-up modems where no one could ever get online during day hours and then at night they were doing maintenance. That is not acceptable for them to not have the capacity they offer for every user all the time. They may want to cut costs that way, but if I ever cannot get online because they wanted to save money by not allowing everyone access as they advertise, then I will switch providers. They need to stop advertising unlimited Internet if they are putting limits on it. And when I called to see where I could go to get a meter to monitor if I go over, they very angrily tell me to go to this statement online and do not help me. How am I supposed to know if I am an average user or not?

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