Reliability and scalability analysis of low cost long distance IP-based wireless networks

Low cost digital radios are sometimes proposed as an affordable tool for the realization of long distance (multikilometric - MKM) point-to-point telecommunication infrastructures in Developing Countries. To analyze the performance and the reliability of an architecture based on use of cheap wireless cards, several point-to-point links ranging from 50 up to 300 kilometers have been implemented in harsh environments. The links make use of commercial IEEE802.11x compliant radios. To reach long distances, off the shelf 802.11-derived communication protocols have been implemented, as well as a simplified proprietary solution employing few minor modifications to the PHY and MAC layers of the standard. Data rate enhancements have been obtained combining and transmitting several channels through the same antenna. Performance and stability have been monitored, continuously, for about 18 months. Reliability and scalability have been analyzed, taking into account the complexity of different kinds of scenarios. Interesting results have been reported, showing that, thanks to its inexpensive features, this technological solution may be used as a starting process to realize backhaul links and transport wideband connectivity in poor and isolated regions.