Files from tftp server

Reading through the cisco ccna voice book, not long started it. With regards to the IP phone boot process, when the phone downloads the initial configuration file from the tftp server (cnf.xml), are these the files we download from the Cisco site and then transfer to the tftp server? Just that the book states the filenames for each phone are SEPmacaddress of phone, so I'm wondering how the tftp server already has the Mac address of the phone and a specific config file for each when in reality this could be the first time the IP phone has contacted the tftp server? Someone else explain where I might be going wrong with this?
Thanks
Thanks
Comments
If not and the TFTP server was totally separate do we need to setup the phone in CUCM (e) and then copy the files to the TFTP server? Just that the book seems to state the TFTP server could be different from the actual CUCM(E) server so I'm puzzled as to how the phone gets the files if this is true.
You can specify the location of the config files in CME (under telephony-services) and it will allow you to specify an external location.