When allocating new data sets, there are two methods you can use to specify the data set attributes. You can customize the data set attributes for your login session using the SITE command, or you can configure the data set attributes for logging in to your server using statements in FTP.DATA. Or, if your system programmer has used the Storage Management System to group together default attributes into named classes, you can specify those class names on the DATACLASS, STORCLASS, and MGMTCLASS statements.