Does uploading slow your download speed?

[BD2003]

I understand that you need to send replies that you are receiving and ready for more data when you are downloading. But not considering that, does uploading interfere with downloading?

For ex, if my line is 640D/90U , and I am uploading at 45, will this essentially cut my download in half since half the line is being used for upload? Or are they totally independent? (aside from the need to send replies to download)

 

[BennyD]

a lil bit i think

 

[iamme]

i've noticed that it does.

 

[vi edit]

Depends on the connection.

 

[MercenaryForHire]

It will, because you'll be receiving the "replies" the other side sends.

- M4H

 

[yoda291]

I don't think you'll notice it if you're using a small part of your upstream, but if someone is occupying your entire upstream, your computer will have trouble sending requests and acknowledgements. I'm not sure if it affects udp transfers that much tho.

 

[Placer14]

I would assume yes because instead of sending information over the line, you're recieving information. I picture a water pipe that can only hold so much water at one time. Regardless of if it's coming or going.

 

[Beau]

Originally posted by: vi_edit
Depends on the connection.

 

[BD2003]

Originally posted by: Placer14
I would assume yes because instead of sending information over the line, you're recieving information. I picture a water pipe that can only hold so much water at one time. Regardless of if it's coming or going.

Thats what I'm thinking. But I'd like to know from someone who can tell me straight out facts.

What about over a LAN? Over a modem? DSL/Cable? Is it depending on the type?

 

[Dedpuhl]

Sometimes it seems like my download speed is cut in half when I'm uploading at full speed (a whopping 20kb/sec).

 

[sharkeeper]

Text

Cheers!

 

[dethman]

mine used to (cable) but now on a new line same company i can up at 25 w/o any slowdowns. don't know why.

 

[Zuph]

When I upload at my maximum of 15 kilobytes/s, my download also drops to about 15 kilobytes/s. Damn you insightbb I called them, they said tough luck.

 

[guyver01]

Originally posted by: sharkeeper
Text Cheers!

good link... people don't realize that while you download, your computer needs to send an ACK packet. If you're doing a massive upload, you will limit how often that ACK packet can go out, thus decreasing your download speed.

 

[Aceshigh]

Originally posted by: Beau

Originally posted by: vi_edit
Depends on the connection.

 

[her209]

If someone takes up your upstream then your downstream is worthless because when you download, you can't send anything out.

 

[Eli]

Originally posted by: Zuph
When I upload at my maximum of 15 kilobytes/s, my download also drops to about 15 kilobytes/s. Damn you insightbb I called them, they said tough luck.

It's not their fault.. lol.. When you're downloading, you're also sending ACKnowledge packets.. that's how TCP/IP works. That's why you can drop packets and not have the connection fail. It's retransmitted if they don't get an ACK.

If you use all of your upstream bandwidth, you're going to slow your download speed down.

Since uploading ACK packets doesen't really take much bandwidth, you can be uploading at probably 70% of your maximum before it noticably starts to slow you down. Of course, it depends on how many open downloads you have, and stuff..

It's funny how most people think of bandwidth... lol...

 

[johnjbruin]

I dont think so.

The data that is sent on the physical wire is at a different frequency than the one at which it is received.
In most connections, a higher bandwidth of frequencies is reserved for downloading, resulting in a higher download bitrate.

I realize, that there is overhead of receiving acknowledgements from the other side, but this overhead is only about 1% since these packets dont contain data and are only packet headers.

This is what i think is true, in case of streaming media etc, when UDP is used, there is no overhead of receiving acknowledgements either.
So 'theoretically', they should be independent.

 

[Sid59]

same here, when i upload to my max, my downloading (webpages and email) slow to a crawl. But if im on Kazaa and multi-threading downloading, it goes pretty fast.

 

[CraigRT]

yeah it affects it...
especially when you're on a crappy cable that your stupid provider caps the up and download speeds....
blah.