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Wide Area Wi-Fi. Sam Bhoot. Wide Area Wi-Fi. Definition: Wi-Fi (Wireless Fidelity) n. – popular term for high frequency wireless local area networks operating on the 802.11 standard. Problem: Local Area Network Question: How to extend this to Wide Area Network? . Wide Area Wi-Fi.
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Wide Area Wi-Fi Sam Bhoot
Wide Area Wi-Fi • Definition: Wi-Fi (Wireless Fidelity) n. – popular term for high frequency wireless local area networks operating on the 802.11 standard. • Problem: Local Area Network • Question: How to extend this to Wide Area Network?
Wide Area Wi-Fi • Solution 1 - Mesh Networks: • Multi-hop systems in which devices assist each other in transmitting packets through the network. • Created using a series of special 802.11b access points (Mesh AP’s) that create a single, scalable wireless network.
Wide Area Wi-Fi • Mesh Networks: • A Mesh AP can send and receive messages and also functions as a router that can relay messages for its neighbors. • Through the relaying process, data will find its way to its destination, passing through intermediate Mesh AP’s.
Wide Area Wi-Fi • Mesh Networks: • A mesh network offers multiple redundant communications paths throughout the network. • If one link fails for any reason, the network automatically routes messages through alternate paths.
Wide Area Wi-Fi • Mesh Networks: • Advantages • Low power transmissions to reach nearby nodes so less interference with radio signals from other nodes. The network is able to benefit from channel reuse, resulting in improved spatial capacity. • Traffic balancing by dynamically routing traffic around a congested node. • Less broadband connections required.
Wide Area Wi-Fi • Mesh Networks: • Disadvantages • Deriving an optimum routing protocol to minimize the number of hops. Dynamic networks eat up bandwidth updating the nodes of the topology. • Ensuring security of packets transmitted from an outside agent stealing bandwidth. • Significantly lowers the capacity of the Wi-Fi network.
Wide Area Wi-Fi • Mesh Networks: • Main Problem: • How to assign IP addresses to mesh nodes? • Solution is to use IPv6 but still impractical. • Use 10.x.x.x numbers and go through and use NAT. • Home Clients will have to go through two NATs. • Leads to complicated issues with proper routing.
Wide Area Wi-Fi • Solution 2 - Repeater / Router: • Software that creates meshes instead of a hierarchical wireless LAN. • The software loads on the wireless adapter card and turns every adapter into a repeater-router, instead of an endpoint looking for an access point.
Wide Area Wi-Fi • Repeater / Router: • End results • Wireless LAN can extend wherever mesh clients exist. • Since users connect to nearest WLAN device instead of distant AP, throughput will be maximum. • Software being developed by MeshNetworks, SkyPilot, Ember, and CoWave Networks.
Wide Area Wi-Fi • Future of Wide Area Networking: • 802.16 Wireless MAN • Feasible backhaul for connecting Wi-Fi Hotspots together. • Base-stations similar to cellular costing about $20k each serving 60 customers with T1 speed connections. • Operates in the 10-66 GHz range with data rates of up to 120 Mbps.