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Better Bandwidth Utilization

Posted by michael on from the neat-hack dept.

jtorin writes "Daniel Hartmeier (of OpenBSD fame) has written a short but interesting article which explains how to better utilize available bandwidth. In short it gives priority to TCP ACKs over other types of traffic, thereby making it possible to max both upload and download bandwidth simultaenously. Be sure to check ot the nice graphs! Also note the article on OpenBSD Journal. OpenBSD 3.3 beta is now stable enough for daily use, so why not download a snapshot from one of the mirrors and try it out?"

6 of 196 comments (clear)

  1. like wondershaper does for months now? by Anonymous Coward · · Score: 5, Informative

    http://lartc.org/wondershaper/

  2. Daniels original email by blkwolf · · Score: 5, Informative

    You can find Daniels original email on the subject at:
    http://marc.theaimsgroup.com/?l=openbsd-pf&m= 10463 0260218727

    It contains a little more of the pf rules than the article does, and has all the relevant information you need except for the nice /.'d graphs

  3. Re:Linux solution by pe1rxq · · Score: 5, Informative

    No it doesn't....
    It is a differend solution to a different problem caused by the same thing....

    The cause is the big cache in the modem, it results in a delay on outgoing traffic.
    One problem is that interactive traffic gets, well, less interactive (e.g. the echo characters in a remote shell have a delay). This is solved in the HOWTO you refered to.
    Another problem is that the downstream acks get delayed resulting in less downstream data. This is solved in the mentioned article.

    A combination of the two would be really great and could probably be done in both linux and openbsd.

    Jeroen

    --
    Secure messaging: http://quickmsg.vreeken.net/
  4. Slashdotted - Mirror by SILIZIUMM · · Score: 5, Informative

    Since the website seems slashdotted now I've set up a mirror. You can see it there.

  5. W. Richard Stevens TCP/IP Illustrated, Volume 1 by puzzled · · Score: 5, Informative



    It seems to me that a great many /. readers have a cursory knowledge of how TCP/IP works. This is true of almost every other topic and I don't have a generalized solution for ignorance, but in this case a quick read of the first volume of Stevens' excellent TCP/IP Illustrated Series should do the trick.

    Reading that book will give you a foundation to understanding how a single endpoint behaves in an IP network. If you want some understanding of the guts of a large scale internetwork I'd suggest the Cisco Press IP Quality of Service book.

    There are a great many things near and dear to /. reader's hearts - the god given right to steal music by treating a retail DSL/Cable connection like a dedicated wholesale circuit being the prime example - that are more easily understood after a read of these two books.

    If you're impatient you can look at my journal - I've covered some of the issues there.

    --
    I am very easy to get along with, but I don't have time to waste being nice to people who are being stupid. -Theo
  6. Re:this may break TCP flow control! by anthony_dipierro · · Score: 5, Informative

    So if the network is congested and an ACK SHOULD time out but doesn't, TCP will keep on flooding the network, ruining the pool for everyone.

    No. If the downstream is flooded, the packets won't be received, and no ACK will be sent. ACKs have higher priority, but even that can't make them appear out of thin air.