Enhancing Service Location Protocol for efficiency, scalability and advanced discovery

This paper presents three new mechanisms for the Service Location Protocol (SLP): mesh enhancement, preference filters and global attributes. The mesh enhancement simplifies Service Agent (SA) registrations and improves consistency among Directory Agents (DAs) by defining an interaction scheme for DAs and supporting automatic registration distribution among peer DAs. Preference filters facilitate processing of search results (e.g., finding the best match) in SLP servers (DAs and SAs) to reduce the amount of data transferred to the client for saving network bandwidth. Global attributes allow using a single query to search services across multiple types. These mechanisms can improve SLP efficiency and scalability and support advanced discovery such as discovering multi-access-point services and multi-function devices. We expect that these techniques can also be applied to other service discovery systems.