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QOS and comcast powerboost

Discussion in 'Tomato Firmware' started by jmntn2000, May 12, 2007.

  1. jmntn2000

    jmntn2000 Network Guru Member

    Comcast has a feature that allows my connection to burst at 10mb for the first 5m of each connection before going back to the usual 6mb and on the upstream will boost to 1.5mb for the first 5m before going back to the usual 384.

    Using QOS I do not realize this "boost". Is there anyway to work around this "variable' pipe speed?
  2. GeeTek

    GeeTek Guest

    What is your reason for needing QOS in the first place ?
  3. digitalgeek

    digitalgeek Network Guru Member

    I agree, it sounds like commcast is "QOS..ing" for you????
  4. larsrya8

    larsrya8 LI Guru Member

    Tomato QOS has no way of determining line speed. You'd have to make the adjustment manually.
  5. snwbdr

    snwbdr Network Guru Member

    I have comcast too same thing, My power boost gets up to 20mb down and now 2.5mb up steady sometimes more. I never knew it gave you an upload boost too. I always had the qos set to 80% of what my upload was before they gave me power boost.

    "A Comcast official said the company is not boosting speeds for particular applications or content, a situation that would likely get Comcast into hot water with Net neutrality proponents, who want network operators to provide the same level of service to all content providers on the Net. Instead it's supercharging speeds for all customers downloading any content--whether it's music, e-mail, pictures or movies--when the network is not being used at maximum capacity."

    How is Comcast able to do this? Like most broadband service providers, Comcast has designed its network to guarantee speeds when usage levels are at their peak. Because the network is rarely maxed out, Comcast usually has excess capacity. PowerBoost allows Comcast customers to take advantage of the extra bandwidth when it's available. But when it's not, the networks still provides the lower guaranteed rates.

    This is old since uploads are now boosted too but here is some info:
  6. GeeTek

    GeeTek Guest

    OK, I'll ask you the same question. Why do you have QOS in the router turned on ? Because everybody else seems to be using it and it has a nice ring ? Sounds to me like you are shooting yerself in the foot for no reason.
  7. snwbdr

    snwbdr Network Guru Member

    Because I wanted to give a higher priority too web browsing than p2p. It didn't originally have the upload boost and I was just pointing out that it now has it. I didn't know because qos has always worked fine for me. If I didn't read this post I would have never known. It isn't really qos because it is only a boost, not constant. When a download starts or upload it will be screaming fast. Then it jumps down to normal. When seeding a torrent I will seed at over 200kb/s then it drops down to 50kb/s shortly after. It is not giving priority too anything. It jumps up everything. I wanted p2p to only have so much upload and download so everything else runs smoothly. When qos is turned off everything gets bogged down. I set my max upload to 2500kb/s and changed the settings on my p2p app. Everything works good now. But Comcast is not qos...ing for me it makes no distinction between what is getting boosted. Still playing around with my settings. Just pointing out that I now get an upload boost too, before it was just 384kb/s. Now when an upload starts it is 2500kb/s then goes down to 384kb/s. That upload will stay at 384kb/s while I start another one the new upload will start at 2500kb/s and will drop to 384kb/s. My browsing,mail,radio, and previous upload will drop, until the boost drops to normal.
  8. GeeTek

    GeeTek Guest

    Oh, I see, p2p. I was trying to figure out what you were doing with all that BW. I couldn't imagine anybody wanting to push p2p upstream as hard as possible. In that case, simply set the p2p rule for your normal bandwidth. p2p will only be missing out on that extra initial short lived burst. Regular traffic will still get the burst. That should be quite survivable.
  9. affer

    affer LI Guru Member

    Yes, but the syntax is a bit obscure so it might take a bit of trial & error unless you can corner an iptables guru. One way to do what you want, would be to define two sets of qos settings. The default set should be based on the full burst speed and then have a script dynamically switch over to your current (lower) qos settings when you exceed the transfer limits that they have set for this 'burst' mode.

    The iptables connbytes function will do this. Connbytes can measure the data transfer and when you exceed the 'burst' limit, mark all of your packets to be reclassified (to your original qos settings). I know people that do this successfully, but I am still trying to figure out the exact syntax myself, as you can see in this post, where I am trying to do something similar. Once you figure it out, you would paste the script into the tomato admin/scripts/firewall page to put it into action.
  10. jmntn2000

    jmntn2000 Network Guru Member

    I understand what you are saying, but I believe that comast speedboost is the first so may bytes of each connection with a global cap i'm sure. So the question is how to keep voip etc prioritized over all p2p but still allow p2p to utilize the burst?

    I don't see how reclassifying is going to get around a variable sized pipe? If I have two connections in burst mode utilzing my full bandwidth they are going to be prioritized higher than the non burst voip? maybe i'm missing something?
  11. affer

    affer LI Guru Member

    Well, you didn't mention that your OP was a moving target. That is, you didn't say anything about voip or p2p in your first post. If you did understand my earlier post, then I can't help feeling that you are trying to solve some problem that you haven't even described to us yet. Is there something else going on that is impacting this situation?

    Anyway, voip will be prioritized simply by putting it into a higher class than the p2p. The p2p qos numbers won't affect voip because it is in a higher class than p2p and therefore always prioritized over p2p. P2p won't have any problem using the higher burst mode speeds, as long as you have based your qos numbers on the higher burst mode, not the lower tier speeds. The only thing left then is qos for other applications at or below (not above) the p2p class when the burst mode drops to the lower tier speed. At this point, downstream qos will be ineffective, being based on the now inflated (burst mode) figures. Which have nothing to do with voip and can be addressed as I outlined in my earlier post. You could also do the same on a coarse basis by writing a handful of rules in Tomato based on the amount of bytes transferred.
  12. n808

    n808 LI Guru Member

    I just upgraded my old Dlink with a Linksys WRT54GL and installled Tomato right away with the intention of running QoS so I would not have to put upload limits in p2p and upload clients like HFS, while maintaining speedy browsing, email services, hamachi remote desktop, Xbox live and Skype.

    So I ran the usual speedtests and found amazing speeds, 20000 kbps down and 1330 kbps up, much higher than I had seen before. I used those numbers for QoS (or 90% thereof) in the QoS config. Then I ran some tests both with torrent and http upload, and was surprised to see the speed drop dramatically (to 350 kbps upload) after almost exactly 7 MB uploaded. After further research in Comcast's fineprint I found the term "PowerBoost" and subsequently this thread. I guess I should have done this research before getting the WRT54GL.

    So I appreciate the attempted answer in this thread, but it has been a while and I was wondering if anyone has figured out something new in this topic?

    It seems QoS will provide some upstream prioritizing benefits with QoS upload limit set according the the initial speed burst. However, it worked much worse than with the previous setup, unless I set upload limits in each application as before (at 75% or so of the throttled upload speed). And when I set these back, I am not sure there was any noticeable improvement to speak of with QoS... In any case, the router is still a great upgrade w a choice of firmwares and features.
  13. froggger

    froggger Guest

    anybody know of a speedtest long enough that powerboost doesn't affect it?
    I find it really hard to get a accurate reading when i get boosted speeds on all the tests.
  14. LLigetfa

    LLigetfa LI Guru Member

    Just download a very large file and do the math.

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