Overcoming Challenges of Aggregating Nodes in Embedded Networks
by Carl Brasek
Cypress Semiconductor Corporation
Network-enabling embedded devices require a different design approach than building traditional enterprise data networks. Devices in industrial and home control applications simply cannot bear the cost of a 10/100 Ethernet connection and full TCP/IP stack when you consider that thousands of devices might be involved. Lighter protocols, such as LonTalk used in LonWorks networks, provide a less complex mechanism for transferring data while supporting key network functions such as remote management. However, for simple nodes such as sensors or lights which may transfer only bytes of data once every 15 minutes, even a light protocol is too heavy.
To balance cost and functionality, such networks often employ multi-tier
architectures that provide connectivity and network intelligence through
aggregation access points (APs). A first-tier AP directly connects several
embedded devices either by directly reading a sensor or by communicating
over a serial port. A second-tier AP connects several first-tier APs using
a higher bandwidth connection. A third-tier gateway may connect and bridge
several second-tier APs to a data network.
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