Zalud’s Blog was told today that Arch Rock Corporation has proposed a new framework for running ZigBee application profiles such as Smart Energy and Home Automation over the industry-standard Internet Protocol (IP).

The Compact Application Protocol (CAP) expands the scope of the ZigBee applications to any IP-enabled device, regardless of the type of wired or wireless network to which it is connected, while preserving the resource-efficiency and compactness critical to devices networked using IEEE 802.15.4 low-power radio. Because the existing ZigBee stack runs only on 802.15.4, ZigBee devices could communicate only with other devices on the same local mesh network, unless users deployed a series of complex, costly and hard-to-maintain protocol-translation gateways.


CAP takes the application-oriented upper layers of the ZigBee stack and runs them efficiently over the same IP foundation used by millions of existing networked devices.

Once built on the standard IP protocol stack, embedded devices such as utility meters, thermostats and load-control devices can become part of the larger IP infrastructure, able to communicate over any LAN or WAN links (e.g., Ethernet, HomePlug, Wi-Fi, IEEE 802.15.4 low-power radio) with other embedded devices as well as remote computers and servers. With the addition of CAP over their IP stacks, such devices benefit from the wealth of service-discovery, binding, device-description and other mechanisms provided by the ZigBee Application Protocol and the ZigBee Cluster Library. Developers' and users' investment in application software built on the ZigBee profiles is protected.

Arch Rock has submitted the CAP draft specification to the Internet Engineering Task Force (IETF) as an informational draft, available at

drafts/draft-tolle-cap-00.txt. A demonstration of CAP is

available to Arch Rock customers and partners on request.