auth-type

Specifies the type of authorization to be used. The type should be “basic” unless you are running a UNIX proxy and are going to use your own function to perform authentication. 

dbm

Specifies the full path and base filename of the user database in the server’s native format. The native format is a system DBM file, which is a hashed file format allowing instantaneous access to billions of users. If you use this parameter, don’t use the userfile parameter. 

userfile

Specifies the full pathname of the user database in the NCSA-style httpd user file format. This format consists of name:password lines where password is encrypted. If you use this parameter, don’t use dbm. 

grpfile

(optional)Specifies the NCSA-style httpd group file to be used. Each line of a group file consists of group:user1 user2...userN, where each user is separated by spaces.