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altis · 08-08-2005, 12:42

Erm...

The maximum payload of a TCP/IP packet is around 1500 bytes. I'm not sure of the exact size of an ACK packet (including headers) but let's make it easy and say 15 bytes. That's a 100:1 ratio.

Then note that, if implemented efficiently, each ACK packet can acknowledge more than one data packet. The number it can simultaneously acknowledge is limited by the size of the 'window' - which is, in turn, limited by the buffer space inside the receiver.

Some peeps report that their upload speed limits their download capability. What is usually happening is that they are uploading loads AT THE SAME TIME. When this happens, the ACK packets are held up by the outgoing data packets.

IMHO for normal surfing, 100kbps upload will be entirely adequate for 10Mbps download.

08-08-2005, 12:42	#45
altis Inactive Join Date: Jun 2003 Location: Warrington ntl:81304 Altitude: 12m (and falling) Posts: 4,499	Re: Rumour from The Bloke in the Pub Erm... The maximum payload of a TCP/IP packet is around 1500 bytes. I'm not sure of the exact size of an ACK packet (including headers) but let's make it easy and say 15 bytes. That's a 100:1 ratio. Then note that, if implemented efficiently, each ACK packet can acknowledge more than one data packet. The number it can simultaneously acknowledge is limited by the size of the 'window' - which is, in turn, limited by the buffer space inside the receiver. Some peeps report that their upload speed limits their download capability. What is usually happening is that they are uploading loads AT THE SAME TIME. When this happens, the ACK packets are held up by the outgoing data packets. IMHO for normal surfing, 100kbps upload will be entirely adequate for 10Mbps download.