FCC hearings: Comcast versus Vuze

FCC hearings: Comcast versus Vuze

Summary: The FCC held its hearing on Comcast's Network Management practices at Harvard University yesterday.  Vuze executive Gilles BianRosa whose company filed one of the two FCC complaints against Comcast reportedly told the FCC yesterday that BitTorrent does not hog bandwidth.

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The FCC held its hearing on Comcast's Network Management practices at Harvard University yesterday.  Vuze executive Gilles BianRosa whose company filed one of the two FCC complaints against Comcast reportedly told the FCC yesterday that BitTorrent does not hog bandwidth.  Since most Internet experts would dispute that claim, I generated the following hard data on the bandwidth consumption of various applications that run on the Internet.

Note: Richard Bennett who was an expert panelist at yesterday's hearings informed me that BianRosa claimed that BitTorrent didn't exceed the contracted limit.  That however ignores the explicit "no server" clause in the terms of service and no broadband service was built to be fully saturated 24x7.  This is why commercial grade T1 lines that offer less than half the speed of broadband connections costing 8 times less are $400 per month.

Bear in mind that the data below is in reference to upstream (upload) bandwidth consumption in kilobits per second since that is the focus of these FCC hearings.  Also note that applications like web surfing hardly use the upstream at all since it's primarily your clicks and URLs that are being transmitted to tell the web server where you want to go.

The following is a graph of the above chart Image showing how BitTorrent hogs upstream bandwidth.

* Corporate VPN telecommuter worker using G.722 codec @ 64 Kbps payload and 33.8 Kbps packetization overhead ** Vonage or Lingo SIP-based VoIP service with G.726 codec @ 32 Kbps payload and 18.8 Kbps packetization overhead *** I calculated that I Sent 29976 kilobytes of mail over the last 56 days averaging 0.04956 Kbps

It is interesting to note that before the advent of P2P applications, Broadband users were primarily downloaders and rarely did they ever upload.  It is for this reason that Broadband networks were built asymmetrically and heavily favored the downstream.  Servers in data centers with commercial-grade Internet connections served and transmitted content and consumers consumed that content by downloading them.

If you're downloading video from a service like Apple iTunes, Microsoft Xbox Live Marketplace, Netflix, or YouTube, you're only downloading and not uploading anything.  Those services pay a lot of money for their own datacenters filled with servers, their own bandwidth, and/or they pay services like Akamai to cache and distribute their content over the entire Internet.

Vuze on the other hand uses a different business model where they don't pay for their own bandwidth and they expect their users to contribute their upload bandwidth to make the service work using the BitTorrent protocol.  Vuze basically gets free distribution because they enlist their own customers to be their servers and bandwidth providers using their own computers and broadband connections.  So instead of paying for commercial distribution, Vuze offloads their bandwidth on to the broadband providers.

<Next page - Exacerbating the Cable and Wireless spectrum scarcity>

Disclosure: Many people have asked me for the source of the data so I will put out the following disclaimer.  As I already indicated in the first paragraph of this article, I am the original source of those charts and graphs.  I’ve written extensively on VoIP bandwidth consumption as the former Technical Director of TechRepublic.  Before TechRepublic, I built and designed networks for a living.  I worked on the routing, the switching, and the traffic engineering of Intranet and Internet based networks.  The in-use bitrates I cited are detailed and include packetization overhead and they can be independently verified.

Exacerbating the Cable and Wireless spectrum scarcity

For a DSL network or a fiber network such as Verizon FiOS, handling the massive upstream traffic is challenging but nowhere near the kind of challenge facing shared-medium technologies like Cable and Wireless broadband providers.  Every DSL or FiOS customer has a dedicated connection to their broadband provider.  While DSL and FiOS providers can't guarantee the 384 kbps to 5 Mbps upstream they advertise for every customer, congestion problems can be dealt with at the gateway terminating the broadband connections.  But no matter how much congestion there is, the dedicated copper or fiber connections going to every home will remain perfectly healthy.  If the backhaul becomes too saturated on a frequent basis, the broadband provider can upgrade the fiber optic transceivers (not the fiber cabling) for the backhaul or at worst they have to replace the router on each end.

For Cable broadband networks which operate on a shared medium (much like Wireless broadband), that much upstream traffic results in packet collisions and a network meltdown if nothing is done to curb the excessive users.  Congestion problems are far worse in a shared medium because the problems can't easily be solved by normal traffic shaping like they can on a DSL or FiOS network and more exotic measures need to be taken.

Cable broadband providers can move up to DOCSIS 3.0 like Comcast's new "Blast" service which increases the upstream capacity 12-fold but BitTorrent and other P2P applications can fill all of the additional capacity.  While the level of congestion would be far better than a DOCSIS 1.1 network that Comcast currently uses for most of their networks, it doesn't negate the need to manage the network and control excessive uploaders.  Wireless broadband providers are even more limited in what they can do because there is only so much the scarce unlicensed spectrum can do.  The licensed spectrum isn't as congested but it's extremely expensive and scarce.

Note: While TV broadcasters no longer have to carry analog TV after February 19th 2009, Cable providers must continue broadcasting analog TV beyond that date and using up valuable cable spectrum.

  Upstream Downstream # of BitTorrent 24x7 seeders to kill network
Cable DOCSIS 1.1 10 Mbps 40 Mbps Less than 26 (1)
Cable DOCSIS 3.0 120 Mbps 160 Mbps Less than 60 (2)
Wireless 802.11g ISP 16 to 20 Mbps shared between up and down under good conditions Less than 10 (3)

  1. Fewer than 26 fulltime BitTorrent seeders saturating their upstream at 384 kbps 24x7 kills a DOCSIS 1.1 network
  2. Fewer than 60 fulltime BitTorrent seeders saturating their upstream at 2 Mbps 24x7 kills a DOCSIS 3.0 network
  3. Fewer than 10 fulltime BitTorrent seeders OR uploaders/downloaders can kill a Wireless 802.11g ISP.  This is because a Wireless LAN is not only shared, but it's shared between upload and download.

Dealing with BitTorrent in a shared Cable or Wireless broadband network is critical to the health of the network.  These networks simply do not have sufficient upstream capacity to be used as a commercial-grade Internet connection meant to serve content to the rest of the Internet.  This is why Cable and Wireless Broadband providers all have explicit terms of service that tell the customer "no servers" or nonstop hogging of the resources that affect other customers.

Had Comcast put a ban on 3rd party VoIP providers in their terms of service, then that would clearly be an example of an arbitrary block designed for the sole purpose of being anticompetitive.  The FCC has shown that they will shut down such anticompetitive behavior in the past with the Madison River Communications case where VoIP provider Vonage was blocked.  But Comcast's terms of service weren't arbitrarily placed there for anti-competitive reasons; they were placed there because of the fundamental limitations of the network.  They policy was specifically targeted at the heaviest bandwidth users only under heavy network duress for minimal impact and maximum fairness to all of the users.

Note: The Free Press likes to complain that certain Comcast users (AP reporters) who were trying to seed small files like the King James Bible were blocked from sending those files to other Comcast users.  Free Press argues that these couldn't possibly be bandwidth hogs because the files were small and the clients were few.  But this is a highly unrealistic and contrived argument because BitTorrent doesn't work very well when there are few users who want a file.  Fewer users means the pool of uploaders are few and they may not stick around to keep the Torrent alive.

The other serious flaw with this argument is that Comcast offers a generous amount of personal webhosting space at no extra charge.  Comcast customer Richard Bennett actually took his personal Comcast web space and put up that same copy of the King James Bible that the AP reporter was trying to send.  Bennett also confirms that he has very few problems seeding this file on his Comcast connection.  By hosting the file on a web server, no scarce upstream bandwidth is used on the Cable DOCSIS network.

When anyone tries to download this file from Richard Bennett's Comcast web space, it is capable of delivering the file at more than 3000 Kbps.  If I try to download it via BitTorrent from Bennett's computer, it would only deliver 384 Kbps at best and tie up Bennett's computer and Broadband connection.  The moral of the story is that a low-bandwidth BitTorrent Seeder simply doesn't exist because there are far better ways of distributing low-bandwidth files.

When a company like Vuze switches to the P2P model where they want to offload their bandwidth and server costs to the Broadband network and home computers, something breaks.  But Comcast isn't singling out BitTorrent or Vuze and targeting a specific protocol because they're permitting BitTorrent downloads and uploads without any sort of throttling.  Comcast doesn't even ban BitTorrent seeders and permit them to go unobstructed most of the day while network conditions permit.  The only thing Comcast does do is block seeding when traffic congestion gets really bad.  That means Vuze or other BitTorrent-based companies still get to freeload off the Comcast network most of the day to deliver content to Comcast and the rest of the Internet, but they don't get to do it at the expense of the vast majority of Comcast customers at the busiest times of the day.

While we might debate whether Comcast's terms of service constitutes adequate disclosure, it is critical that the FCC declares Comcast's specific targeting of bandwidth hogs only at crucial times of the day as "reasonable network management".  While it's always popular to slap down a large corporation like Comcast, banning this sort of network management will have grave consequences on the Cable and Wireless broadband industry as a whole.  It will have a chilling effect on small independent wireless operators like Brett Glass and harm the very competition our Nation seeks to foster.

<Return to top>

Disclosure: Many people have asked me for the source of the data so I will put out the following disclaimer.  As I already indicated in the first paragraph of this article, I am the original source of those charts and graphs.  I’ve written extensively on VoIP bandwidth consumption as the former Technical Director of TechRepublic.  Before TechRepublic, I built and designed networks for a living.  I worked on the routing, the switching, and the traffic engineering of Intranet and Internet based networks.  The in-use bitrates I cited are detailed and include packetization overhead and they can be independently verified.

Topics: Government US, Broadband, Government, Networking, Telcos

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  • Couldnt have said it better myself...

    George you pointed out specifically in your article that Comcast COULD change to the DOCSIS 3.0 networks vice the DOCSIS 1.1 network they have now (which a previous discussion I believe it was determined this has been around since 1999)..so Comcast deserves to be smacked down because THEY caused a lot of the problems on the network today by not investing properly into the network itself. Thus they have to resort to these low tactics and impede the legitimate use of torrents. Yes you say if they get some huge fine it will stall the roll out of DOCSIS 3.0...which may be true but we all know they have lots of money to throw around anyway so its a moot point, HOWEVER, dont you think that would get all the other companies in high gear rolling out the same technology so THEY dont get hit with a fine? Point is Comcast could have done more to help alleviate these issues from their end and they failed and must be dealt with appropriately -- even if it means a fine along with a managed rollout cycle since they couldnt do it themselves.
    JT82
    • Now you tell me what we should do with all those small independent wireless

      I'll say it again: Being crappy isn't a crime. There are serious ramifications to any kind of FCC or Congressional action.

      Now you tell me what we should do with all those small independent wireless ISPs who are barely afloat who can barely deliver 20 mbps shared up and downstream.

      Always remember to be careful of what you ask for, because you might just get it (metered Internet)
      georgeou
      • Thats not whats at the subject of discussion..

        For one, those "small independent wirelesss ISP's" are not at the point of discussion. Further, I seriously doubt there are that many around -- and if there are they are already in areas where competition is more pronounced. What IS at the point of discussion is that Comcast has blatently ignored the advances in DOCSIS revisions to allow higher throughputs and a higher quality as opposed to what they have now by forging TCP resets to "limit uploading". You said yourself DOCSIS 3.0 allows a 12-fold increase in the upload capacity for each loop ...theoretically this allows them to grossly oversell the loop as they historically have done.
        I wholeheartedly agree, metered internet is DISASTER and I personally NEVER want to see that in mainstream use (however, maybe for a small subset of customers, it may be a viable option..especially for low level users who want a "cheap" yet fast pipe to the net). Metered internet isnt in the mix here, its having a SOUND management strategy for the network management and proper allocation of resources and they wouldnt be in this hot water.
        Oh on them small wireless ISPs...they should move to a market where they can grab the users they are aiming for (email, web surfing, non-heavy downloaders/uploaders) and help foster competition in markets where its much needed to help keep the big boys like Comcast from being crappy and screwing over the consumer OR maybe a federal grant/tax relief is in order for these types of ISPs to get them to grow. Take your pick.
        JT82
        • Oh really? You think regulations only stop at Comcast?

          "For one, those "small independent wirelesss ISP's" are not at the point of discussion. Further, I seriously doubt there are that many around "

          Oh really? You think regulations only stop at Comcast?

          "I wholeheartedly agree, metered internet is DISASTER and I personally NEVER want to see that in mainstream use (however, maybe for a small subset of customers, it may be a viable option..especially for low level users who want a "cheap" yet fast pipe to the net). Metered internet isnt in the mix here, its having a SOUND management strategy for the network management and proper allocation of resources and they wouldnt be in this hot water."

          Oh really? But the people you're supporting are pushing it and if the FCC bans want Comcast is doing, you'll see the only other alternative that you DON'T want. Oh and don't think that they'll just roll out metered for a few people, it will be for everyone. Right now my mother pays $15/month for her DSL service at 768 Kbps down and 330 Kbps up unmetered. I pay $19/month for 1.2 Mbps down and 320 Kbps up. Have you looked at the Australian plans the EFF was pushing?

          "maybe a federal grant/tax relief is in order for these types of ISPs to get them to grow"

          Hey it's always nice to get free money from other tax payers isn't it? Here we have some of the more affluent people demanding more handouts. It use to be a chicken in every pot and now it's going to be a fiber in every home and a computer in every room, off the backs of your fellow tax payers.
          georgeou
          • Nope. They apply to everyone.

            "Oh really? You think regulations only stop at Comcast?"
            Nope. They apply to everyone equitably. Tell me why Cox communications can manage their network w/o using these tactics (and they are a shared medium just the same as Comcrap) OH WAIT..they invested in their network and moved to DOCSIS 2.0/3.0. So in turn they can better handle their subscriber load.

            "Have you looked at the Australian plans the EFF was pushing?"
            Yes i did and frankly they sucked. Metered internet is bad. I was merely stating that broadband prices will increase because companies will cite ridiculous claims like "we need more bandwith and we are investing all the money i our network". Once broadband pushes 50-60 dollars for basic service...people are going to want "cheaper" pipes and I see metered internet being an OPTION at that point while those on unmetered plans will pay a signifigant premium -- unless the market dictates otherwise. I pay $34.99 for a dry-loop DSL plan from Verizon at the 3.0 down/768k up, which considering isnt too bad. I mean look at the metered/unmetered plans the national wireless carriers rolled out regarding their cellular/texting services - case in point.

            "Hey it's always nice to get free money from other tax payers isn't it?"
            Pray tell how this is from other tax payers? I was suggesting that these "other wireless isp's" cut some of their cost down so they can roll out a stronger network and maybe get more subscribers to make up for them "just bearly getting by". It would also be good for these ISPs to do a little market reserach and maybe they can help themselves a little bit too. Tax breaks like this dont come at a cost to everyone else, but the impact would be negligable because there just simply isnt too many of these guys around. Verizon Wireless, AT&T, Sprint and Tmobile would be the only viable competitors in the Wireless internet specturm anyway -- Unless wi-MAX gets rolled out and revolutionizes things..wireless ISPs will not have the saturation the wired counterparts do.
            JT82
          • No, Cox isn't using DOCSIS 2/3 that I'm aware of

            No, Cox isn't using DOCSIS 2/3 that I'm aware of. It would be big news if it were.
            georgeou
          • Check the Hampton Roads, VA market...

            In the Hampton Roads Area in South East Virginia (Norfolk, Chesapeake, Virginia Beach, Portsmouth, Suffolk, Newport News, Hampton) and I confirmed with their Tech Support back in 2004 when i lived there that infact they were using DOCSIS 2.0 at a minimum. They increased their overall speed limitations and the "premium" plan that I wanted at the time was not available because I only had a DOCSIS 1.1 compliant modem and had to move to a DOCSIS 2.0 modem to take advantage of it.
            JT82
          • Re: Cox Dociis 2/3

            I don't know what Cox uses, but in markets where they compete with FIOS (I believe they compete in Virginia), cox offers something like 10 or 20 mb/s downloads at between 1 and 5 up (I don't recall).

            Unfortunately, it seems like the only time we see any improvements in broadband infrastructure is when Verizon's fios service comes to town.

            Personally George, I think that part of the problem IS COMCAST's.

            You can defend their practices all you want, but the bottom line is that they are promising more than they can deliver. If people are increasingly uploading, maybe it's time to stop promising ever greater download streams and start shifting some of that bandwidth to uploads.

            Maybe it's time to promise a minimum level of sustained service.

            Even before torrents, I preferred DSL. I couldn't download as fast, but I got what I was promised. And yes, I know the stories about your mom. But if you get 1mb downloads, you get 1MB downloads. If you get 300kb uploads, that's what you get.

            Comcast IS worse than Cox -- I've had both, there's just no comparison -- but neither are as good as the service I got from SBC and Verizon Ave.

            P.S., I've stated many times how lousy Comcast was in Dallas. I talked to my old roommmate a week or 2 ago and he said that the improvements after Time warner took over were dramatic.
            notsofast
          • Cox manages their network too.

            http://www.theregister.co.uk/2007/11/20/cox_bagging_edonkey_swaps/
            georgeou
          • At least they are being honest about it..

            for one..they are being up front and not trying to cover it up. second, they should be dealt with pretty much the same way with what comcrap gets handed down to them by the FCC sans anything for lying, misrepresenting information to the public, OH and lets not forget...trying to SCREW a public hearing.

            I am not a HUGE seeder, i just occassionally download off of torrents, so this isnt a HUGE deal for me. But if you are going to do something, own up to it, which is what REALLy irked me about comcrap and the NOT so comcastic experience. I still never had any performance issues or anything like that I did when attached to a Comcast network, so obviously Cox does it better or more transparently. Keep in mind right now there is a witch hunt out there on ISP's to see whos managing what and how...
            JT82
          • We don't want to go metered.

            Brett Glass here; my comments to the FCC were referenced at the end of the article. We don't want to go metered, because it will anger consumers who are tired of being nickled and dimed to death already (e.g. by cell phone companies). What's more, users would be charged for things beyond their control -- such as big Microsoft bug fixes and huge updates from Symantec and Intuit. So, instead, we try to manage bandwidth more gracefully. And our Terms of Service for residential users simply forbid P2P. Yes, we occasionally get a complaint from a World of Warcraft player (we explain to them that updates ARE available without BitTorrent; you just have to know how to get them). But I daresay that overall our customers are much happier than customers of the local cable company.
            woot@...
          • Thnaks for your reply, please email me

            nt
            georgeou
        • I am a small, independent wireless ISP

          I operate a free community wireless ISP. I have had no choice but to implement bandwidth-hog throttling, due to any number of users that leave their computer on all day downloading (or uploading). I try to be fair-- I monitor total bytes in 5 minute increments. If a particular internal IP to external IP pair are consuming a large amount of traffic, their connection is re-prioritized to a low setting (other traffic gets preference). If the internal IP hops to multiple external IPs (as one might see with torrent feeds), then that IP is reprioritized for all of their traffic. I do not discriminate against any application, port, or protocol-- just gross number of bytes.

          It works, is fair (IMHO), and was not too tough to implement.
          RestonTechAlec
          • Seems fair to me...

            And you are not implementing forgery to do it. Bravo!
            JT82
        • There are at least 8000 independent wireless ISPs

          Several surveys have reported that there are at least 8000 WISPs (independent wireless ISPs) operating in the continental US. And, contrary to what you say, they often cover areas that the "big guys" (the telephone and cable companies) don't serve and don't WANT to serve. If they go under, large portions of rural America will be off the Net. And because the FCC hasn't given them any spectrum to call their own (or allowed them to get it at auction; the auction system is slanted toward cell phone providers), they're stuck on congested unlicensed spectrum too. With equipment that has a limited capacity because of the rules pertaining to that spectrum. They have no problems so long as they can manage bandwidth. But if the FCC steps in and says they can't (and that's what the Free Press petition asks the FCC to do), they're hosed. Dead. Gone.
          woot@...
          • No one is arguing the ISP cant manage their bandwith..

            Its just HOW they do it...sending forged TCP reset packets is not reasonable network management when you have not exhausted other resources by say upgrading to DOCSIS 2.0 or 3.0. I would tend to agree the spectrum auctions are slanted toward the big guys due to the high cost of the licencing .. however why not lobby the FCC/congress to help out? There are plenty of senators that would listen ...now getting action is another story. I live in a rural area and I know of no wireless ISP's other than from the major cellular guys, everything else is DSL.

            Maybe the little guys should work together to form an alliance to help foster the innovation of wireless rather than rely on antiquated methods of network management. Like the guy above said about his small indy wireless ISP..he does it all with priority...not outright forgery.
            JT82
          • Yes, they are. Read the Free Press petition.

            Free Press specifically states that it wants the FCC to ban "discrimination" -- which it defines as throttling or blocking some packets but not others. That means no blocking of worms; no prioritization of VoIP; no P2P mitigation.

            As for the RST packets: they aren't forged at all. There's nothing in the TCP standard (go read the RFC) that says that a RST packet must be originated by one of the parties to a session. (In fact, the standards provide for a third party to manage a session.) The standards do say that to identify the session the packet must bear the addresses of the parties to the TCP session and the ports that they are using at each end. That's exactly what a RST packet contains.

            It's worth noting that routers routinely send RST packets to indicate that one of the parties to a connection has dropped off the Net (e.g. when a dialup user hangs up). Yes, it uses the address that was assigned to that host, but it's certainly not spoofing. It's a command, indicating the session which is to be terminated. And it's not an "antiquated" method of management; it's perfectly up to date. It's being used by products such as WebSense and Sandvine to manage networks.

            As for your comments about spectrum management: Alas, the government tends to listen to large corporations that make big campaign contributions. So, they are favored in the spectrum auctions.
            woot@...
          • I agree with you 100%.

            I for one don't wnat to see ISPs being restricted from controling thier own services when needed.
            No_Ax_to_Grind
    • Won't help.

      No matter how big the pipe, users will fill it and at times over fill it. It's human nature when you sell them "all you can eat" services.
      No_Ax_to_Grind
      • True but..

        Yes users will always "fill the pipe" regardless of size but thats also mainly to the ISP overselling the loop. Comcast has been ignorant of the DOCSIS 2.0 and 3.0 standards that have been out since 2001 and 2006 repectivly, so a lot of this is on them. Other providers like Cox communications, which I personally have used in the past, never had these issues so obviously they are doing something right in management terms.

        Yes the BT/P2P folk seeding can cause issues on the upstream, but maybe this is where the ISP for DOCSIS networks such as Comcast should implement a P2P gateway and throttle the connections that way (to a reasonable number of course) and make all the users aware rather than forging TCP resets.
        JT82