Frottle

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Frottle: Packet Scheduling and Quality of Service for Wireless Networks. Currently available on Linux wireless gateways, this open source project aims at optimizing a wireless network use:

Frottle works by scheduling the traffic of each client, using a master node to co-ordinate actions. This eliminates collisions, and prevents clients with stronger signals from receiving bandwidth bias. [...]

Access to the network is controlled by the frottle master, sending each client a control packet (token) which contains information about how much data can be sent at this time.

Each client receives its token and sends any required data, one at a time. This eliminates collisions, and with a reasonable signal packetloss is virtually zero. Also, since each client gets a limited slice of the bandwidth, everyone can get fair access regardless of their signal strength.

Ah! Token Ring on WiFi. Token Ring was invented by IBM in 1970 as a local area network technology based on the rotation of a token within a loop-shaped network. Only the node that has the token can send packets on the wire. I was sold a Token Ring network by IBM in 1989 on the promise that it would be much more efficient (16 Mbps) than TCP/IP over Ethernet (10 Mbps at the time). We discovered only after closing the network loop that the network was performing at 4 Mbps, the speed of the slowest machine, a PC/RT 6150 the same "sales engineer" from Big Blue had sold us a year before. When you think of such a network topology, bottlenecks linked in a circle, it makes absolute sense.

But I digress. Gosh do I feel old sometimes... [Via Boing Boing]