In 2004, CAP was reviewed and adopted by the Organization for the
Advancement of Structured Information Standards (OASIS). The latest ver-
sion of CAP (v1.1) was adopted in 2005. It has since been recognized and put
into use by numerous public and private organizations involved in alerting
activities, including the International Telecommunications Union and the
U.S. Centers for Disease Control Public Health Information Network (CDC-
PHIN). Adoption of CAP is expected to continue to grow in the coming
years, as a variety of organizations seek ways to leverage digital platforms
and distribution methods for alerts.
14.4.1 CaP basic Message Structure
A CAP message is an XML document with a structured arrangement of infor-
mation elements. Each CAP message contains an <alert> block, which may
contain one or more <info> blocks, each of which may contain one or more
<area> and <resource> elements. Taken together, these elements establish
the basic structure of a CAP message. Figure 14.2 shows the basic CAP mes-
sage structure adopted for the HazInfo Project in Sri Lanka (Evaluating Last-
Mile Hazard Information Dissemination [HazInfo] 2007), using three <info>
blocks per message to provide multilingual alerting in English (en), Tamil
(ta), and Sinhalese (si) for various natural hazards, including tsunamis.
CAP message structure showing multiple “info” blocks used to provide multilingual alerting.