12
6LoWPAN and RPL
12.1 Overview
Traditionally, battery-powered networks or low-bitrate networks, such as most fieldbus networks or 802.15.4 (see Chapter 1 for details) were considered incapable of running IP. In the home and industrial automation networks world, the situation compares to the situation of corporate LANs in the 1980s: “should I run Token-Ring, ATM or IPX/SPX?” translates to “should I run ZigBee, LON or KNX?”
IP, with its concept of layer 3 routing and internetwork technology, has made those debates about incompatible networks obsolete: the vast majority of LANs and WANs today run IP, and many people can hardly remember which layer 2 technology their IP networks are running on. Almost any layer 2 technology can be used and will simply extend the IP internetwork.
The same transition to IP is now happening in the home and industrial automation worlds. 6LoWPAN and RPL have made this possible.
12.2 What is 6LoWPAN? 6LoWPAN and RPL Standardization
The Internet Engineering Task Force (IETF) 6LoWPAN Working Group was formed in 2004 to design an adaptation layer for IPv6 when running over 802.15.4 low-power and lossy networks (LowPAN or LLN). The work included a detailed review of requirements, which were released in 2007 (RFC 4919).
In practice, however, the 6LoWPAN is not restricted to radio links, and the technology can be extended to run over other media, for instance it has been extended to run over low-power CPL (www.watteco.com) or G3 OFDM CPL. IPv6 is also being ...
