I've written an article before on how booters work but still i see time and time again confusion, even most of the programmers who write booters don't even understand why their booters work so i'm going to try and explain it.

Best way to imagine a booter is just a pipe with a pump on the end which pumps the water down the pipe to yahoo.

the client has a pipe which gets the water from yahoo (which was sent by the booter / other people) .

How to boot someone? Send more water to the person than the person can get out, once the water gets full it over spills and the person is booted, now at yahoo's end when you send an instant message to a user yahoo takes that packet then delivers it to the client now if that client is busy, instead of throwing away that packet yahoo stores it in a buffer (buffer is like a swimming pool, you can fill it but not too much or it will overflow) now as you keep sending on packets unless the client is awake and able to get them the data will get stored in the buffer and it will keep getting stored in the buffer until the buffer is reached when this happens yahoo assumes the ID is no longer active so yahoo disconnect the ID.

If the client happens to be using a good connection nice and fast and is able to take from the buffer faster than the person can upload it to fill the buffer the client will not be booted, it takes roughly 130k of data to fill that buffer so if a person can only upload at 10k/s but the person being attack can download at 20k/s that person will not be booted.