I have a western digital mybook word NAS. Using the afp protocol file transfers were very slow. I knew there had to be a way to make your AFP NAS more responsive. It seems slow when you try to connect to it from a mac using AFP, but its lightning fast when you connect to it from windows.
The solution (for me at least) was to use a different protocol to connect. I suspect that the afp implementation in the mybook world isnt that great.
The mybook world offers 4 protocols to connect: smb:// cifs:// afp:// and nfs://
It looks like the AFP protocol uses bonjour to try to figure out the devices name and ip address, then tries to connect to the mybook, then lets you browse the device and actually do stuff, like transfer files.
I tried connecting using all the different protocols [in osx finder > go > connect to server > cifs://ipaddress] and downloading a file.
cifs seemed to me to be the fastest overall, so ill stick with that when using the mybook. If you are having issues with your mybook world or any other NAS from your mac, you might want to change the protocol from AFP to something else that your box offers to make your AFP NAS more responsive :)
I no longer have the mybook NAS – I have a zyxel NAS, its much better, and even using afs its much faster (it has gigabit ethernet ports and is connected to a gigabit switch using cat5e in my homelab which helps a lot over the fast-ethernet that the mybook offers). I connect my machines to the zyxel NAS with sshfs to mount the remote drive now, so transfers are both faster and encrypted, which is nice.