HSMM

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Collecting data for the high speed multi media network. Essentially, this involves using inexpensive wireless routers to create a network. Some of the 2.4 GHz frequences of 802.11b/g are in the ham band, which means we (hams) can operate them under part 97 rules instead of part 15 rules. (More power.) WWI has done this sort of thing for about 2 years during Field Day and the VHF contests. You can view the network map. VHF 2005

Reference Links

I haven't really hit the motherlode just yet. The ARRL page is useless for this subject.However, after several hours of searching, these links seem to be worth while.

http://www.n5oom.org/hsmm/ - Good link with power point presentations. Although, the downloads are slow. Very good article on microwave propagation. These guys supported a bicycle event using a fairly complex network installation.

http://en.wikipedia.org/wiki/Hinternet - Wikipedia provided a good starting point.

http://d-star.mit.edu/index.php?title=Main_Page - Not really high speed, but digital (D-Star)

http://www.vawifico.org/doku.php - Wireless Community Network Pages

http://en.wikipedia.org/wiki/Wireless_mesh_network - Wireless Mesh from Wikipedia

Firmware and Software

dd-wrt - firmware upgrade to the linksys WRT-54GS. After two years with openwrt, I switched to this one because it seems more complete.

openwrt - another firmware for the linksys. I started with this set because it was free.

Radio Mobile - Great tool for analyzing RF paths.

Quick Facts

One node will support about 20 users. Hidden transmitter problem applies.

802.11 Networks and Wireless Community Networks from O'Reilly are good references.

Barnet's Emperical Fade estimate - % of year where fade exceeds a specific depth below free space for a given path and frequency. Use fade margin of 20db.

http://home.satx.rr.com/wdubose/hsmm/Ping_Callsign_ID_HowTo.html - You need to ID every 10 minutes. Use Linux ping.

Experimenting with the WRAP board.

For the HSMM/hinternet, hams are prohibited from using encryption. Apparently, the ARRL has petitioned the FCC for relief, but I haven't found any documents granting the exception.

Vendors

http://www.netgate.com - Netgate

http://www.jefatech.com/category/hsmm/ - JefaTech

http://www.fab-corp.com - FA&B