The most practical step that can be taken to improve so-called 'speed' is to do less.

Few people ever mention the configurations in effect re: the number of assigned 'slots' for Download, Upload, Upload Queue and 'hosts'.

With a 56k Dial-Up connection you should be limited to 1 Download and 1 Upload and NO Upload Queueing. There is also almost no sense in being connected to more than 2 or 3 'hosts'.
You should also disable 'Allow Others To Browse' your shared folders.

If you have a particularly important file that you are D/Ling, you should cease Uploading.

ALL of the things mentioned above 'consume' your available bandwidth.
Bandwidth refers to 'a capacity to conduct' information.
Just imagine a pipe... Small inner diameter will only permit so much 'flow rate'...

No matter what publicity may surround one client or another in terms of claims for 'speed' and multi-source transfers, and no matter what foolish default settings result from these claims, the user must still take the responsibility for reducing connection slots. This benefits the entire community.

For those with greater capacity, i.e. 'bigger bandwidth', these comments still apply.
A 256/128 ADSL connection, in today's reality (as far as others and their pitiful speeds due to wrong configurations), a maximum of 4 Upload slots and 4 Upload Queue slots seems to be optimum.
Downloads are another matter as you can easily get away with 8 slots with the typical upload speeds of today... But, (And this is a very crude best possible result) it is a simple matter to divide @27kBs by 8... That is about the same as you could best expect from a 56k Dial-Up per slot !!! No matter what the 'nifty numbers' show, you cannot exceed your bandwith (capacity).

A very good rule is to set everything to the minimums and slowly, over many days of observation, increase slots - ONE at a time.

If you have a truly 'broad-band' connection, and you wish to share any modestly large number of files, you should NOT allow yourself to be an Ultrapeer.

Transfers that are completed in the shortest period of time use far fewer resources of the network.

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