Cable Forum - View Single Post - Download unusable while uploading on 50meg

darren.b · 01-03-2010, 00:50

That's how it is. When you download, you have to send ACK packets back to whoever you are downloading from to let them know you got the "chunk" fine and dandy. This uses your upstream, and currently on my 20Mb pipe it needs 62KB/s for a 2.5MB/s download just for ACK packets. Approx 67% of the upstream just for return packets alone. The 50Mb up/down ration is even worse.

If you max your upload out, there's no space for those ACK packets to be sent so your downloads run sloooow.

Throttle your uploads to about 80% of its top speed and it should give you some decent download speeds.

On a symmetrical connection this isn't really an issue due to the small amount of space required for ACK's, but as we know VM's broadband is almost one way. Huge down pipe, tiny up pipe. Yay VM!

01-03-2010, 00:50	#2
darren.b cf.addict Join Date: Jan 2004 Posts: 183	Re: Download unusable while uploading on 50meg That's how it is. When you download, you have to send ACK packets back to whoever you are downloading from to let them know you got the "chunk" fine and dandy. This uses your upstream, and currently on my 20Mb pipe it needs 62KB/s for a 2.5MB/s download just for ACK packets. Approx 67% of the upstream just for return packets alone. The 50Mb up/down ration is even worse. If you max your upload out, there's no space for those ACK packets to be sent so your downloads run sloooow. Throttle your uploads to about 80% of its top speed and it should give you some decent download speeds. On a symmetrical connection this isn't really an issue due to the small amount of space required for ACK's, but as we know VM's broadband is almost one way. Huge down pipe, tiny up pipe. Yay VM!