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Posted By: Windfall Uploading lessens download speeds - 05/02/04 04:48 PM
I can download several files at once without a problem, however, when I try uploading (only 15k) a file to anyone, the download speeds drop. I am using a cable modem, i have already addressed the issue with them and they resolved it is not on their end. My downloads are no where need my capacity so what ever could be the problem?
Posted By: Mentality Re: Uploading lessens download speeds - 05/02/04 05:43 PM
Uploads depend upon the receiving persons connection. If you have 1mb cable and the person you're sending to is on 56k dialup, then the upload will still go at 2/3/4kbps.

You can try the following commands to speed DCCs:

/fsend on
/pdcc on
/dcc packetsize 8192

However, these commands don't do much, if anything at all, so don't expect huge changes wink

Regards,
Posted By: DekuHaze Re: Uploading lessens download speeds - 05/02/04 06:46 PM
Uploading tends to effect downloading for most people, because of the way ISP's handle the flow of traffic. Unfortunitely, short of changing ISP's, there's nothing you can do about it...
Posted By: d00dman Re: Uploading lessens download speeds - 05/02/04 07:41 PM
This is very normal. Nothing is wrong with your cablemodem.

When downloading, you are still uploading acknowlegement packets to the sender. There is no escaping this with TCP connections... it is part of the design to make sure things are transferred in the proper order, etc. To make things worse, DCC also sends an ACK back to the sender, so that uses more of your upstream (this is the main point about why DCC is a poor protocol for file transfers).

If you are using all of your upstream uploading a file to somebody, then there is none left to send ACK packets back to the sender, so eventually you start receiving the files slower. This is horribly noticable on cablemodems, since the modems have their own queue but it is large and very inefficient.

If you'd like to learn more about this, google for "Quality of Service" or "bandwidth throttling".

HTH,
-chris
Posted By: Windfall Re: Uploading lessens download speeds - 06/02/04 12:45 AM
Ment: I have already used all those settings

Others: I am still unclear why uploading a file at 14k/s takes a 35k/s download down to 8k/s. My downstream is more than capable than handling a measly 30k, so why should my incapabilities of uploading effect those downloads?
Posted By: d00dman Re: Uploading lessens download speeds - 06/02/04 06:17 AM
I explained why. Your upstream and downstream are not independent. Use *any* program and do this on *any* cablemodem, and you will see the exact same thing. Upload a large file to a ftp server and then try to visit any website and download something... it'll be extremely slow.

FWIW, your upstream cap is most likely 128kbps, which is 16k/s. With TCP and DCC overhead, sends at 14k/s are probably the maximum you can achieve.

-chris
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