The Common Alerting Protocol (CAP) is an XML-based data format for exchanging emergency alerts and public warnings among different alerting technologies. CAP allows a consistent warning message to be disseminated simultaneously over many different warning systems, in order to increase warning effectiveness and simplify the warning activation task for responsible officials. The Extensible Markup Language (XML) is a W3C-recommended general-purpose markup language for creating special-purpose markup languages, capable of describing many different kinds of data. ... In the USA and Canada, an AMBER Alert is a notification to the general public, by various media outlets, that a confirmed abduction of a child has happened. ... Some emergency situations can reach an entire population. ...

By normalizing alert data across threats, jurisdictions and warning systems, CAP also can be used in the detection of trends and patterns in local warning activity, such as might indicate an undetected hazard or hostile act. From a procedural perspective, CAP reinforces a research-based template for effective warning message content and structure.

The CAP data structure is backward-compatible with existing alert formats including the Specific Area Message Encoding (SAME) used in Weatheradio and the broadcast Emergency Alert System, while adding capabilities including: Specific Area Message Encoding or SAME is the protocol used to encode the Emergency Alert System in the U.S. for broadcast stations. ... Weatheradio is a special radio service available over much of North America that transmits weather warnings and forecasts 24 hours a day. ... The Emergency Alert System (EAS), is a national system in the U.S. put into place in 1997, superseding the Emergency Broadcast System and administered by the Federal Communications Commission (FCC). ...

• Flexible geographic targeting using latitude/longitude “boxes” and other geospatial representations in three dimensions;
• Multilingual and multi-audience messaging;
• Phased and delayed effective times and expirations;
• Enhanced message update and cancellation features;
• Template support for framing complete and effective warning messages;
• Digital encryption and signature capability; and,
• Facility for digital images, audio and video.

Background

The National Science and Technology Council (NSTC) report on “Effective Disaster Warnings” (November, 2000) recommended that “a standard method should be developed to collect and relay instantaneously and automatically all types of hazard warnings and reports locally, regionally and nationally for input into a wide variety of dissemination systems.” For other uses, see November (disambiguation). ... This article is about the year 2000. ...

In 2001 an international, independent group of over 120 emergency managers began specifying and prototyping the Common Alerting Protocol data structure based on the recommendations of the NSTC report. The project was embraced by the non-profit Partnership for Public Warning and a number of international warning system vendors. A series of field trials and long-term demonstration projects during 2002-03 led to the submission of a draft CAP specification to the OASIS standards process for formalization.

The CAP 1.0 specification was approved by OASIS in April, 2004. The Organization for the Advancement of Structured Information Standards (OASIS) is a not-for-profit, international consortium that drives the development, convergence and adoption of e-business standards. Members themselves set the OASIS technical agenda, using a lightweight, open process expressly designed to promote industry consensus and unite disparate efforts. OASIS produces worldwide standards for security, web services, conformance, business transactions, supply chain, public sector, and interoperability within and between marketplaces.

Based on experience with CAP 1.0, the OASIS Emergency Management Technical Committee adopted an updated CAP 1.1 specification in October 2005.

Current Implementations

According to a CAP 1.0 Fact Sheet, CAP implementations have been demonstrated by agencies and companies including: United States Department of Homeland Security; National Weather Service; United States Geological Survey; California Office of Emergency Services; Virginia Department of Transportation; GeoDecisions, Inc.; E Team; Blue292; Warning Systems, Inc.; Comlabs, Inc.; mobileFoundations; Ship Analytics; MyStateUSA; IEM, Inc.; Hormann America, Inc.; Oregon RAINS. The United States Department of Homeland Security (DHS) is a Cabinet department of the federal government of the United States that is concerned with protecting Americas people from harm and its property from damage. ... The National Weather Service (NWS) is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration (NOAA) of the United States government. ... The United States Geological Survey (USGS) is a scientific agency of the United States government. ...

During early 2005 the U.S. Department of Homeland Security (DHS), in partnership with the Association of Public Television Stations, demonstrated "digital EAS" broadcasts over public television digital TV transmitters and satellite links in the Washington, D.C. area and nationwide.

CAP is the foundation technology for the proposed "Integrated Public Alert and Warning System," an all-hazard, all-media national warning architecture being developed by DHS, the National Weather Service and the Federal Communications Commission. CAP is also being used as an integrating technology for an enhanced Tsunami warning system as cited in the Internet Society's 2005 "Public Warning Network Challenge". A tsunami warning system is a system to detect tsunamis and issue warnings to prevent loss of life. ... The Internet Society or ISOC is an international organization that promotes Internet use and access. ...

Additional Information

The CAP Cookbook is a wiki for developing and sharing implementation notes and other supplemental documentation for CAP.