This fall, San Francisco will implement the largest mesh network for monitoring parking to date. Around 6,000 wireless sensors from the San Francisco company Streetline will be fixed alongside as many parking spots, monitoring both parking availability and the volume and speed of passing traffic. The city hopes that displaying information from the sensors on Web maps, smart phones, and signs on the street will reduce the traffic and pollution caused by circling cars.
A mesh network differs from a typical wireless network in that there’s no central transmitter: every node can transmit to every other node. Mesh networks have generally been used for environmental monitoring, or to grant wireless devices Internet access.
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