NeuStar, Inc. Columbia U. Nokia Siemens Networks The Common Alerting Protocol (CAP) is an XML document format for exchanging emergency alerts and public warnings. Different organizations issue alerts for specific geographic regions. The Location-to-Service Translation (LoST) protocol provides a way to discover servers that distribute these alerts for a geographical region. This document defines the Service Uniform Resource Names (URN)s for warnings in the same way as they have been defined with RFC 5031 for citizen-to-authority emergency services. Additionally, this document suggests to use LoST for the discovery of servers distributing alerts.