Router

When a Windows NT application has a print job it wants to send to the printer, it communicates with the client side of the spooler (Winspool.drv). This file makes an RPC to the server side of the spooler (Spoolss.exe), which makes a direct API call to the router (Spoolss.dll—which is also on the server side of the spooler).

The router passes control of the print job to the appropriate print provider. In the case of local printing, the local print provider takes the print job. If the print is going to a server on the network, the router passes the print job to the appropriate remote print provider—the Windows remote print provider or the Novell NetWare print provider.

Do not confuse the software router component of the Windows NT spooler with the physical hardware router used in networks.