Hi, I've been using a simple home network using a belkin 11MBp/s router that works fine. 4 windows 7 machines all use the network, 2 desktop and 2 laptops. sometimes i'll go to copy something large and deliberately not use the wireless given its speed limitation, and plug a wire in to do the copying. some of the time, it will work fine and copy at the routers max speed of around 11megabytes per second, until the file is finished.
A great deal of the time though, it'll only copy at around 5/6MBp/s, but the wierd thing is that its not copying at that speed, as if i look at the network activity on task manager or using a desktop gadget it'll max out the connection speed for a few seconds and then go idle for even longer and repeat like this until the file's done which needless to say takes a lot longer. I do have eset firewalls on all machines, however I know its not to do with that as I've tried disabling them before trying to copy a file and it still happened.
oh, and restarting everything doesn't help either!
he's using the local network. He is his OWN provider.
There's a lot of areas that could be going wrong. You need to isolate and test your devices. I'd start with iperf and test your network performance. This program generates data to be sent instead of reading from your HD. This way you can specifically test your network cards.
Your switch or your cables could be bad to.
Another thing to note is that copying lots of small files will cause your speed to drop as the overhead of starting a file takes longer than copying the actual file. Well, for SMBv1 anyway.