[liberationtech] Mesh Networks?

[Danny O'Brien]

On Jun 17, 2011, at 2:27 PM, Steve Weis wrote:

I'm not dismissing mesh networks in general. I was specifically talking about examples of municipal WiFi mesh networks like Rooftnet and Meraki. The article you linked to is in reference to FabFi, which is an ad hoc long-range radio network connecting to local meshes. My point was that extending a local WiFi mesh to cover a large area (e.g. Kabul or Nairobi) is difficult in practice. Other technologies might be better suited.

Just as a point of reference, FabFi's Nairobi installation serves 13 homes and has only been able to operate at a peak of 1Mbps, which is 20% of their capacity [1]. They averaged about 4GB of total traffic a day during April. They are experiencing frequent outages as of a couple months ago [2]. That's not surprising since power and network connectivity can be intermittent in Nairobi.

[1] http://fabfiblog.fabfolk.com/2011/04/hump-bringing-it-all-together.html
[2] http://fabfiblog.fabfolk.com/2011/03/banwidth-crisis.html

I'm not entirely adding new information here, but I spent a fair bit of time researching WiFi mesh in 2004 when many of these technologies were being first explored. The general concern then was that building mesh on 802.11 commodity hardware was  challenging because the niggling details of theoretical mesh routing models were still in their infancy then, and applying them to the real world (and a real RF environment) was exposing serious and hard to debug challenges, especially on a platform that wasn't built for mesh.

I think when many people think of mesh now, they're still considering using WiFi, but they may be unaware of the already large amount of practical knowledge about the limitations of commodity WiFi tech to pull this off.

Effective mass hacking, I feel, comes from having a wide variety of fairly well-known and commoditised tools that can be repurposed and composed together to new ends. I think everyone wants that commodity tool to be WiFi, but I think the last few years have shown that it's by no means easy to do this.

Alternatively, we may have enough practical knowledge now to build something stable and reproducible out of it, but the knowledge is badly distributed among a lot of practictioners, some of whom may already have given up, and some of whom may be trapped in attempting to provide commercial services out of what they know.

I'd love a frank summary from the Meraki, LocustWorld, PortlandTelco and the 802.11s folks of what's been happening in the last few years. Maybe this information is being collated somewhere: but I think it would be more rewarding to collate that past experience, than start from scratch all over again.

d.











On Fri, Jun 17, 2011 at 12:34 PM, elham gheytanchi <elhamucla at hotmail.com<mailto:elhamucla at hotmail.com>> wrote:
if that is the case, why is the state department funding mesh networks in Afghanistan? (reported in the NY times)? FabFi is expanding its work:

http://www.nytimes.com/slideshow/2011/06/12/world/20110612-INTERNET-ss-3.html

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