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Cross-Platform Printing

There are several strategies for providing cross-platform printing. One is to install software components onto the network operating system so that all clients can access network printers through one server. For example, you could install software on a Windows NT Server that allows Macintosh, Unix and even NetWare clients to print to a Windows NT printer. This can also be done on a NetWare or Unix server. The issue at hand is the time and cost associated with installing and configuring these software components on your server. If you have two network operating systems, such as NT and Unix, adding the necessary software is not much of a problem. But if you are supporting additional clients, this job can get pretty complex. For a Unix server, installing SAMBA will give Windows NT (or OS/2 LAN Manager) users access to Unix-based printers. SAMBA is also available for NetWare 4.x and other platforms, such as VMS. To the end-user, the printer is displayed in the Network Neighborhood, as it is with other Windows NT-based printers. SAMBA is a free source product available on the Internet. It has a strong following and is used by many companies, large and small. In addition, there are vendors in many countries that provide commercial support for SAMBA. There are also products from Sun and other vendors that provide the same type of functionality.

An easier method is to make the printer the central point of integration. Most, if not all network printers support at least Novell 3.x, NT, Unix and often Macintosh printing requirements. The main concern here is whether or not the network controller in the printer is robust enough to behave correctly in supporting multiple protocols. Many of the network interfaces support a round-robin approach, where the printer checks to see if there is an incoming print job using a specific protocol. While most of the network printers on the market support a wide variety of protocols, be sure to make sure your specific network needs are addressed. This is especially true if you are using a token-ring network, since some printer vendors support only a subset of network protocols used on token-ring-based network printers. At a minimum, an enterprise printer should support TCP/IP, IPX/SPX (both bindery and NDS support) and AppleTalk. Depending on your needs you might also need DECNet, DLC or LocalTalk.

Note that the printer's network interface adapters are subject to the same type of vulnerabilities that other network devices face. For instance, Internet Security Systems (www.iss.net) recently determined that many of the older HP JetDirect cards can be compromised by security attacks. In some cases, the text display on the front panel of the printer can be programmed to display any 16 character message. Even more serious attacks can freeze the printer, requiring a reboot or hard reset. To make matters worse, network printers with embedded HTTP servers do not provide any security controls beyond simple passwords and text, which are transported over the wire in clear text. Currently, no printers support SSL (Secure Sockets Layer) or SHTTP (Secure HTTP). This of course, opens up security holes. But luckily, the worst thing that can happen is that the printer will be reconfigured, requiring a few hours of support without any loss of valuable data.