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HSMM-MESH ™ PRESENTATION FOR THE ARES MEETING Bill Wallace KC0TGY. Question?. How would you like to have a communications system for public agency use that could have; Wifi speed internet “type” service between selected locations
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HSMM-MESH™PRESENTATION FOR THE ARES MEETING Bill Wallace KC0TGY
Question? • How would you like to have a communications system for public agency use that could have; • Wifi speed internet “type” service between selected locations • net meeting with live audio and video between any locations • e-mail service between any location on the network • ability to send and receive any type of document as an attachment to an e-mail at current wifi speeds, and • full error checking on all transmissions
Question? • How would you like to have a communications system for public agency use that could have; • Supportable with emcomm battery power supplies • Without the requirement of actual Internet access • On Amateur Radio frequencies • Without wires • For less than $300 per link
What is HSMM • The HSMM name was coined by the ARRL to distinguish Amateur use of WiFi protocols by Amateur Radio Licenses. • High Speed Multi Media = HSMM • HSMM Working Committee created as an ARRL working group in 2001 • Created to develop high speed (above 54 kbps) digital networks for the Amateur Service • Encourages the use of “off the shelf” consumer equipment
Terms Part 97 We know what this is • Part 15 Wifi rules and regulations • ISM (Industrial, Scientific, Medical Bands) • 802.11 b/g WiFi • Point-to-Point / Point-to-Multipoint • BDA (Bi-Directional Amplifier)
Bands Part97AmateurRadio 2.45 Ghz 2.39 Ghz ISM ISM 2.40 Ghz 2.45 Ghz 2.50 Ghz
Bands 2.39 Ghz Part97AmateurRadio & ISM ISM 2.40 Ghz 2.45 Ghz 2.50 Ghz
IEEE 802.11b Channels Channel Low Freq. Center Freq. High Freq. 1 2.401 2.412 2.423 2 2.406 2.417 2.428 3 2.411 2.422 2.433 4 2.416 2.427 2.438 5 2.421 2.432 2.443 6 2.426 2.437 2.448 7 2.431 2.442 2.453 8 2.436 2.447 2.458 9 2.441 2.452 2.463 10 2.446 2.457 2.468 11 2.451 2.462 2.473 Bands
Power Limits • Part 15 Unlicensed low power Wifi • Maximum Transmitter Power Output (TPO) is 1.0 watt or 30dBm • The maximum EIRP power allowed is 36dBm (4 watts) for Point to Multipoint • Point to Point allows for much higher formula based EIRP (I think this is 6 watts)
Power Limits • Part 97 Ham regulations • Maximum Transmitter Power Output (TPO) is 100 watt or 50dBm • No EIRP limits
dBm to Watts (FAB-Corp)
Equipment • Inexpensive • Higher Power • Modified Firmware • High Power Amplifiers (BDAs) Do Not Use • Antennas
Range • Ranges are normally in the 300 feet or less range with currently available Part 15 equipment, but can be pushed much farther with a non-part 15 antenna. • Range experiments are over 134 MILES at sea in Italy, 79 MILES in the California Coastal Mountains, 34 MILES per leg in the Shenandoah valley, 10 MILES across Austin, Tx.
SECURITY OF SIGNAL • WEP and ENCRYPTION are acceptable to ARRL and FCC. “Not obscuring the message, securing the message, password, etc. • Is the control link to our repeater encrypted or password protected? Does this “obscure the meaning of the message”? • Planning to move the center frequency to in between channels. No one will see the channel, NOT EVEN NET-STUMBLER, ETC.
Routers / Client Cards Linksys WRT54GL Router Modified Firmware 250mW Max Output? (Linksys) Z-Com XI-325HP+ External Antenna Connectors 300mW Max Output (Pasadena Networks, LLC)
BDAs / Antennas 2.4GHz BDA 1W Max Output (Part 15) 1.8W Max Output (Part 97) (FAB-Corp) Comet Omni 15.4 dBi (FAB-Corp)
Antennas DieCast Parabolic Grid 24dBi Gain (FAB-Corp) ARC Wireless Patch 19 dBi Gain (FAB-Corp)
Homebrew Pringles Cantenna (Spicey Cajun) 12db Gain (est.) (Gregory Rehm) Bi-quad Attached to DSS Dish 27-31 dbi (est.) (Trevor Marshall)
Uses • Digital Video with Remote Control • Emergency Data Communications (e-mail, file transfers including images) • VOIP (Voice Over IP) Telephones • Repeater linking
2.4 GHz WiFi is Fast • • The RF links are around 54 Mbps • – Packet Radio/APRS 0.0012 Mbps • – Pactor III .003 Mbps • – D-Star DD 0.128 Mbps • • Home Service • – FiOS (Fiber Optic) 2 Mbps up / 15 Mbps down • – T1 1 Mbps • – DSL 0.768 Mbps, 0.512 Mbps, 0.368 Mbps • – Dialup 0.014 – 0.056 Mbps
Limitations • 2.4GHz Propagation • Busy Spectrum • However, Non Part 15 use is secondary • Part 97 use is Primary for a change! • Caution:We do not want to disturb the big dogs. Bidirectional Amps are seldom necessary. Stay off channels 1 and 6. Use height and directional antennas to avoid interference to WiFi users and suppliers.
Local Groups Direction • Point to Multi-Point Router at Hospitals/clinics • Mesh of Access Points Feeding From/To Hospital --- with enough relay stations properly located, no problem.
HSMM NETWORK DIAGRAM ACCESS POINT ACCESS POINT 2 Omni outdoor antenna for local area 2 @ $70 each = $140.00 2 routers WDT54-GL 2 @$60 = $120 2 Antenna Poles 2@$20 = $40 2 laptops (personal machines.) (network control stations.)
ACCESS POINT SYSTEM DIAGRAM RELAY UNIT OR ANOTHER ACCESS POINT USERS LINKSYS ROUTER CONTROL COMPUTER COULD ALSO BE FILE SERVER OR E-MAIL SERVER LOCAL AREA ANTENNA
HOW FAR CAN WE LINK APs TOGETHER NEEDS PHYSICAL LINE OF SITE FROM AP TO AP UNIT IN SOME VERY FLAT OPEN TERRAIN, DISTANCE TO HORIZON PLUS ANTENNA HEIGHT EFFECT. IN SOME MOUNTAINOUS TERRAIN WITH ACCESSIBLE OPENING IN THE FOLIAGE, 34 TO 75 MILES BETWEEN AP POINTS AND APs IN BETWEEN. IN ST. LOUIS? HOW HIGH CAN YOU GET THE DISH AND ROUTER AS A PACKAGE? REMEMBER DISH MUST BE PRE- POINTED OR ROTATABLE TO POINT AT ACCESS POINTS. NO FOLIAGE BETWEEN POINTS, CLEAR LINE OF SIGHT……
Ok What is a network • Review: Ad Hoc or sometimes called a Peer to Peer network • Point to Point network. • Node address manually assigned • looks like this.
Ok, What is a network • Review: Infrastructure network • star shaped network. • Nodes joint and drop off. • Access Point controls many service functions like assigning addresses.
Ok What is a MESH network • Now, What is a MESH? • Here is a MESH (Sample 2 link)
Characteristics of a MESH • In a MESH each node has the intelligence to link to any other node it can physically hear on the network. • In a MESH each node self builds tables used for routing messages trough the MESH to the desired destination. • Connect a node to a resource (internet, video camera, etc) all nodes have access to the asset.
Characteristics of a MESH • In a MESH as a new node appears, the routing tables are recreated to account for the new node. • In a MESH, if any node disappears, the routing tables are recreated to account for the lack of that node. • In a MESH, duplicate transmissions of messages are stopped by a node.
MESH Network Diagram • Broken net self heals
HSMM-MESH™ • A HSMM-MESH System is HSMM equipment usually COTS, special free software / firmware with MESH software loaded over it on a router. • Does not require a separate repeater • Ready to go right now.
HSMM vs. Packet Packet • 1200 bps to 19200 bps • Requires special (rare) knowledge to set up, use • Requires special software to use • Routing is difficult • Uses common radios & antennas • TNC’s are expensive • Generally uses UHF down to HF • HSMM • 60 kbps to 54 mbps • Requires special (common) knowledge to set up, but use is common knowledge • Software is commonplace • Routing is simple • Equipment ranges from common to uncommon • Equipment is cheap • Runs on 900MHz and higher
Ham Equipment Icom D-STAR • Runs on 1.2 GHZ, combines FM voice and 128kb data • Requires separate, proprietary analog and digital repeaters • System of components including mobile radio, voice and data repeaters and a 10GHz backhaul radio • Mobile has ethernet, USB connections • Pricey!