SH>   I use a firewall for that.  I suppose another way would be to use Sync
 SH> or Mystic to launch your dos bbs software... I /think/ they have the
 SH> option to auto block IP's don't they?

Yes, Mystic can auto block IPs after X connections from the same IP in X
amount of time, and it can also block by origin of connection (ie entire
countries).

It also has your traditional "blacklist" and "whitelist" where you can add IP
addresses to a list to never or always allow them, and you can also use
wildcards.

It has a built in matrix login menu so you can create a BBS software menu
without requiring the user to log in.  You can also use MPL to script a menu
or do whatever you'd like without requiring user login.

--- Mystic BBS v1.12 A1 (Windows)