Samba expert Jerry Carter looks at the Imprints architecture, a project to implement a UNIX equivalent of the Windows NT APW.
In this article, I examine an alternative to the Windows NT Add Printer Wizard (APW) for installing printer drivers from a Unix/Linux host.
Imprints (Installation Manager of Printer Driver Retrieval and Installation for Samba) is a project to implement a Unix equivalent of the Windows NT APW. It has been taken on in part by the Samba Team, VA Linux Systems, and Hewlett-Packard. However, printer driver installation is only part of the picture. Figure 1 shows the different parts of the Imprints architecture.
The basic idea behind the design of Imprints was to provide a central repository for users and administrators to locate, download, and install Windows printer drivers on Samba print servers. Although HP has played a large role in sponsoring the work, Imprints itself will be vendor-neutral.
The server portion of Imprints is composed of a database server that contains information and locations of various printer driver packages. This server can be queried over standard HTTP get requests and should therefore be available to most administrators behind firewalls. The server's database consists of records containing data about each known printer driver package. For example, each driver record contains a URL from which the Imprints installation client can download the package as well as a public key that can be used to verify the package's integrity (notice that I said "package's," not "driver's").
Once downloaded, the installation client will attempt to install the printer driver on the defined remote server using the username and password provided by the user. If the username/password pair can be authenticated by the remote server and has the appropriate authorization), then the printer driver(s) is (are) installed and the new printer is created. Figure 2 displays a screenshot of a successful installation.
The GNOME Imprints installation client
From Samba's point of view, the process of creating a new printer via the Imprints installation client is identical to that of using the Windows NT APW. In fact, Imprints utilizes Samba's rpcclient and smbclient tools to issue the same MS-RPC and file copy operations as an NT client. This means that Imprints can also be used to install printers on remote Windows NT print servers (if you have any).
At this time, Imprints is about to enter its first beta release cycle. For more information on Imprints, visit the project home page at http://imprints.sourceforge.net/.
Gerald Carter has been a member of the SAMBA Team since 1998, and he is employed by VA Linux Systems. He is currently working with O'Reilly Publishing on a guide to LDAP for system administrators. He holds a master's degree in computer science from Auburn University, where he was also previously employed as a network and systems administrator. Gerald has published articles with various Web based magazines, such as Linuxworld, and has authored instructional course for companies such as Linuxcare. In addition, he acted as the lead author of Teach Yourself Samba in 24 Hours (Sams Publishing, 2000), and he actively gives tutorials at systems administration conferences.
During his spare time, Gerald enjoys running, hiking, playing music, and bible study. He resides with his beautiful wife of seven years in Dadeville, Alabama.