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Save the World! What’s appropriate for global networking? Where do we go from here? • Networking costs money • Market payback has driven network infrastructure • Without networking, what do you do? Can you take part in the global market? • Is networking a right? • Who pays? Pieces of the net • Connections – Wiring, especially fiber, expensive – Wireless initially more expensive, less overall cost • Routers – Expensive ones make network use efficient – Cheap ones, but not very efficient. QoS! Bigger pieces • Network backbone: – ATM infrastructure. REALLY expensive! But uses network more efficiently. – IP Gigabit infrastructure. Cheaper, but doesn’t go very far, doesn’t use network efficiently. Wiring expensive. – Dedicated WAN systems: Frame, T1, and more. What do we want to do? • Applications – – – – – – E-mail Browsing a web site Creating a web site Video/audio conferencing Receiving small messages Sending small messages E-mail • The usual way - Simple Mail Transfer Protocol (SMTP) over Internet links. • Can be slow links. • Older ways - E-mail via shortwave radio modems, dial-up to dial up networking, other radio systems. Browsing a web site • The usual way - HTTP via an Internet link • Can be cached - Local (proxy) server stores pages, and passes them on to users. • Synchronization technologies (Avantgo and more) can deliver pages for later browsing. • Wireless web, voice web? Low bandwidth browsing. Creating a web site • The usual way - editing files online (UNIX) or uploading files to web sites. • More advanced modern ways - XML creation of content. • Can E-mail updated sites, especially if using XML. • Experiments with updating web sites using XML for mountain climbing. Receiving small messages • Usual way - peer to peer chat clients, cell phones, etc. • Can be VERY low bandwidth • Multiple radio systems can carry the information from a big transmitter to a large region. Transmitting small messages • Same method: chat clients, cell phones. • Still low bandwidth • Need power at your end to send a signal a long distance. How to get information around cheap • • • • • Low-speed radio networking high-speed radio networking Satellite messaging Satellite network connectivity By foot! Low-speed radio • Often used in Amateur Radio • Emergency use • TNC - Terminal network controller • CHEAP! $500. • 1200 bps or 9600 bps. Long range. • Messaging, GPS, other data packets. Cheap high-speed radios • IEEE 802.11b standard • 11 Mbps over short range. 1 Mbps short. • Can be extended to large range over flat terrain • cheapish: $500$1,500. • Real Internet Advanced Radios • Extreme range • High speed (4.5Mbps to 33+ Mbps) • Able to handle yucky topography • More expensive: $3000+ • “Social Intranets” Satellite solutions • Satellite highspeed Internet: Expensive, but fast. Slow possible. • Satellite phone services - dial up network and SMS. • Satellite messaging - cheap two way SMS-like messages. By Foot?! • Can place content, deliver content, via CD-ROM/DVD-ROM, etc. • Can update via messaging systems. • Limited, but possible. • Don’t knock it. The government does it! Hybrid solutions • Direct PC - high speed downlink of data from space. – Uses phone link back – Can use other routes back, like radio networks, maybe even SMS? – Has very high speed “package” delivery. – Small, cheap, easy to use. What’s best? • Up to you! Go build solutions. • Different situations determine needs – Arctic different from here – Arctic different from Africa, Malaysia. – Different topography, needs, culture • “Society Intranets” can help maintain culture. Internet can impact on culture. • Who pays?