I maintain a small ISP net which includes an FTP server. I am continually amazed at the unauthorized access attempts to this resource just because it's out there.
Once upon a time I allowed anonymous access and all I got was an endless stream of exploits by dullards who thought they could outwit me with embedded illegal filename characters and various scripting attempts which were all pretty futile prior to them ever arriving on my patio.
So now I'm just a lock down crazy anus much like the sysadmin group at the City of Columbia because they're stupid while I'm simply fed up. I can maintain an anonymous public access resource but simply choose not to be bothered. The continual requirement of my premium off time in the pursuit of making things accessible and more importantly SAFE for my bonafide users was just more than I cared for in light of that preponderance of exploiters out there anywhere and everywhere.
So now you need both an account and specific credentials to gain access to the FTP server. Wasn't always this way and just because you have an account doesn't make you automatically eligble for FTP privileges. Found that requirement out the hard way too.
I have it nailed down to a specific list of allowed client addresses as well. So DHCP credentials likely won't do it for you. How's that for an anal retentive policy in the best traditions of the City of Columbia, SC ... land of the tard sysadmin group ?
Microsoft addicts — just can't do anything in the absence of a gui and a snap in.