frottle: Defeating the Wireless Hidden Node Problem

jasonjordan writes "The West Australian FreeNet Group was the first to go War Flying - and now we've released "frottle" (freenet throttle) - an open source project to control & manage traffic on fixed wireless networks. Such control eliminates the common hidden-node effect even on large scale wireless networks. frottle works by scheduling client traffic by using a master node to co-ordinate - effectively eliminating collisions! Developed and tested on the large community wireless network of WaFreeNet, We've found it has given us a significant improvement in network usability and throughput. "

Comments

Re:Just read the article..

[RevMike]

..and all this is, is a glorified token ring implemented at the OS layer on top of 802.11.

Color me unimpressed.

Why are you critical of the solution? It appears to work well and is inexpensive. What is wrong with that?

A friend who used to work for a "baby bell" was involved with a project to provide VoIP and video services, as well as internet, over their DSL infrastructure. The problem that they ran into was that IP, as supported by their commodity DSL equipment, did not support QoS. Their solution was to tunnel a more advanced network protocol (ATM I think) over the entire DSL IP connection. Then they ran their voice and video over ATM directly and ran IP as another tunnel over ATM. It wasn't elegant, but it was cheaper and more effective than manufacturing new devices.

Anytime you can use commodity off-the-shelf hardware, you can usually save money.

Re:TokenRing?

[El]

It's also an order of magnitude more difficult to implement (due to problems like recovering lost tokens) and was limited by spec. to 16Mbits/second, with a higher proportion of those bits devoted to overhead. Oh, and chipsets to do Token Ring were an order of magnitude more expensive. Token Ring is to Ethernet as Steam Engines are to Internal Combustion engines -- yes, if they'd put as much time, energy, and money into developing Token Ring as they have into Ethernet, it would be a better technology than Ethernet (mostly because like you said, worse case packet delivery time is deterministic). But they haven't!