Auto Config is a neat feature that I'd love to use for our servers, but who thought it was worth spending the time and effort to implement support for NFS and CIFS shares, while leaving the most common auto configuration protocols out? TFTP, FTP, HTTP... any of those would have been better choices. The server just needs to grab a single xml file. NFSv3 doesn't play well with firewalls. CIFS is not even worth talking about (because everyone has a Windows server or Samba available, right?). Both, at least in this configuration, have the same security as TFTP (none).
Would really like to see support for TFTP added in a future firmware release. Auto Config is useless without it in our environment.