Hi, Is anyone looking at running IP over narrowband very high frequency (VHF) and ultra high frequency (UHF) data radios? A couple of major issues come to mind.
First, bandwidth is extremely limited and valuable. These radios may provide bandwidths of only 9,600 bits-per-second (bps), 4,800 bps, or even less. Networks composed of these radios might be viewed as _wide-area_ wireless sensor networks (WSNs) (in contrast to the "local-area" WSNs typically built with 6lowpan devices). Link distances in these narrowband networks may be kilometers or even tens-of-kilometers long. The narrowband radios used in these networks may transmit with one to five watts of power. In my view, the extremely low bandwidths of these networks, combined with the very high energy cost of transmitting a bit, is likely to drive different engineering tradeoffs in protocol design (compared to 802.15.4 networks, where link bandwidths are relatively high and the cost of transmitting a bit is relatively low). For example, in a narrowband network, it may make much more sense to compute or store information whenever possible, rather than transmitting it (more than one) over the air. While I have not yet done the analysis, it seems to me that it is quite likely that the engineering tradeoffs make in 6lowpan are different than the engineering tradeoffs that might be made in a narrowband radio network. Perhaps, there is utility in a collection of IP-over-narrowband-radio RFCs. Second, there is a pretty complete lack of standards for narrowband data radios, most importantly at the physical and MAC layers. While this topic is outside of the purview of the IETF, it is a serious impediment to building interoperable products. It might also complicate the process of standardizing IP-over-narrowband-radio specifications. -tjs _______________________________________________ 6lowpan mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lowpan
