http://www.rfc-editor.org/rfc/rfc6739.txt
RFC 6739: Synchronizing Service Boundaries and Elements Based on the Location-to-Service Translation (LoST) Protocol, H. Schulzrinne, H. Tschofenig2012-10-01T23:00:00-00:00This document defines an XML protocol to exchange these mappings between two nodes. This mechanism is designed for the exchange of authoritative elements between two entities. Exchanging cached elements, i.e., non-authoritative elements, is possible but not envisioned. Even though the element format is reused from the LoST specification, the mechanism in this document can be used without the LoST protocol. This document defines an Experimental Protocol for the Internet community.