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QoS and ACK packets

Posted: Tue Jun 12, 2012 1:56 pm
by Djoss
Some users already asked the question before, but I did not find a clear answer.

So the questions are:
  • - What happen to outgoing ACK packets?
    - In which class those packets are going to?
    - Do we need to create a rule for those packets on the upload side?
    - If yes, how should we create this rule?
Take the case where there is a rule to put HTTP download in a fast class. When the upload link is saturated, how do I make sure that TCP ACKs generated by the download gets higher priority than other upload traffic?

Re: QoS and ACK packets

Posted: Tue Jun 12, 2012 2:54 pm
by blueacid
Tcp ack packets are 64 bytes long. Therefore you can create a rule for any tcp packet of 64 bytes to get a high priority.

Re: QoS and ACK packets

Posted: Wed Jun 13, 2012 5:30 am
by Djoss
Thanks for your answer.

So basically, I guess that rule for ACK packet is required to make sure that the download side is not affected by upload traffic having less priority.

Re: QoS and ACK packets

Posted: Wed Jun 13, 2012 6:54 am
by pbix
Folks,

I added
http://www.gargoyle-router.com/wiki/dok ... re_special
and
http://www.gargoyle-router.com/wiki/dok ... s_priority
to the QoS Wiki to help folks with these commonly miss-understood subjects.

In response to the OP's other question, pretty much all classes require rules to route traffic into them. To route HTTP traffic into a class in the uplink we set the destination port to 80 in the corresponding rule.

Re: QoS and ACK packets

Posted: Thu Jun 14, 2012 7:33 am
by Djoss
Thank you very much. I think it should now be clear :)