The Service Location Protocol (SLP) is an Internet Engineering Task Force (IETF) standard, documented in Request for Comments (RFCs) 2165, 2608, 2609, 2610, and 2614. SLP provides a scalable framework for the discovery and selection of network services.
SLP enables the discovery and selection of generic services, which could range in function from hardware services such as those for printers or fax machines, to software services such as those for file servers, e-mail servers, Web servers, databases, or any other possible services that are accessible through an IP network.
Traditionally, to use a particular service, an end-user or client application needs to supply the host name or network IP address of that service. With SLP, however, the user or client no longer needs to know individual host names or IP addresses (for the most part). Instead, the user or client can search the network for the desired service type and an optional set of qualifying attributes.
For example, a user could specify to search for all available printers that support PostScript. Based on the given service type (printers), and the given attributes (PostScript), SLP searches the user's network for any matching services, and returns the discovered list to the user.