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Mesh Networks

motherjones.com

91–100 of 103 posts

Re: Mesh Networks

#91
http://www.nytimes.com/2011/06/12/world/12internet.html?page...

For best UX, set your "Referrer:" header to google.com

Also, I think Cisco paid over a billion for one mesh community network's project. I think a YC cofounder may have been involved in that project. Not sure. Its Cisco brand name is Meraki.

It appears portable autonomous networks (i.e. no telco needed) are useful and valuable for many, diverse reasons. I posit that if you can build your "no telco required" network from affordable parts and can get it to work consistently, then it has value, irrespective of whatever "intended uses" for it you might have in mind.

Of course, I could be wrong.

Re: Mesh Networks

#92
post #37
post #20

I saw an article about this a little while ago. If anywhere in the world could support a wide scale mesh network, it would have to be the Bay Area. It would be a really cool experiment to blanket a part of the Valley in mesh wifi: I imagine it would be very doable to raise $100K and send 1,500 mesh routers to people in Palo Alto or SOMA. Open Mesh has some really cool low-cost ($50 - $75) hardware that seems to just…

And yet another mesh network, from HacDC hackerspace in Washington. http://project-byzantium.org/

"The goal of Project Byzantium is to develop a communication system by which users can connect to each other and share information in the absence of convenient access to the Internet. This is done by setting up an ad-hoc wireless mesh network that offers services which replace popular websites often used for this purpose, such as Twitter and IRC." - from http://project-byzantium.org/about/

Re: Mesh Networks

#93

Earlier quoted context omitted.

I skimmed your paper, but I'm curious, based on your research into this area what an alternative would be to create private networks for citizens without laying out cable everywhere (which theoretically could also be tapped).

As opposed to wireless which doesn't have to be tapped (i.e. can just be listened in on with antennas)?

This is true. And if the FCC were to give up spectrum for use in mesh networks, they could always require that no encryption be used. They mandate this with amateur radio. A HAM's license could be revoked if he was caught sending encrypted transmissions.

Re: Mesh Networks

#94
post #25

While this is a great solution for places without easy last-mile connections, it seems to me this would still be vulnerable, as one compromised connection would essentially allow the same kind of snooping that we've got going on now. Does anyone know whether this is so, or how to protect against snooping, as I would assume there is some implicit level of trust required for a network like this to stay secure.

A sort of invitation only controlled by social relations? not perfect but at least, misbehaving people can be trackable.. should be based in social connections and trust.. the old school policy

That creates an active incentive to physically lean on people to roll up networks.

cjdns works by requiring people to exchange keys with someone out of band to get access to their mesh, and to me that just seems as fundamentally defeating the purpose.

Yes, that means you need to build a system where bad guys are hard to impossible to track down and throw off the mesh. The problem is if you create a system where misbehaving people are trackable, then good guys can be tracked too.

Re: Mesh Networks

#95
post #65

It seems like there's been another surge of interest of late in mesh networks. Last time this happened, I wrote up a piece explaining why mesh networks are really a poor solution for circumventing censorship: http://sha.ddih.org/2011/11/26/why-wireless-mesh-networks-wo... . Since then, some of my colleagues and I at Berkeley wrote a more academic version of this blog post. The talk is available here: http://www.youtu…

I'm wondering if software defined radio has anything to contribute here. Ultra wideband could help to mask the radio signals. Software defined antenna's could help with the directionality problem. This stuff is expensive today, but maybe not in a few years.. I'm really surprised that P2P doesn't scale on a mesh and would like to understand this better. I do research on message passing algorithms and obviously trees (…

In general, the market has overtaken hobbyist hacking by a wide margin. Any technique you are considering has already been considered and either adopted or abandoned by the Broadcoms of the world. Basically all radios are now SDR-ish but their firmware only contains a highly-optimized implementation of a single protocol (e.g. 802.11). Sure, a spinal code PHY with a mesh MAC will beat 802.11 by some percentage, but it costs 10x more because it's an FPGA instead of an ASIC so you end up switching back to Atheros/Broadcom radios.

Re: Mesh Networks

#96
post #63

If you wanted to start a mesh network in your town, is there advice on how to protect yourself from legal liability in case someone does something clearly illegal with it? Do mesh operators have the same "safe harbor" protections? What if the FBI shows up on your doorstep and says "give us access or go to prison" ?

What do you do if your ISP says 'shut it down'?

The mesh itself should probably be an ISP. For whatever reason I get the impression that ISPs give downstream ISPs much more benefit of the doubt than they give end customers.

Re: Mesh Networks

#97
post #65

It seems like there's been another surge of interest of late in mesh networks. Last time this happened, I wrote up a piece explaining why mesh networks are really a poor solution for circumventing censorship: http://sha.ddih.org/2011/11/26/why-wireless-mesh-networks-wo... . Since then, some of my colleagues and I at Berkeley wrote a more academic version of this blog post. The talk is available here: http://www.youtu…

I've only skimmed your first link and parts of your paper, but in my opinion it misses the mark several places. For circumventing censorship, a pure wireless mesh is not in any way a requirement, for example.

The point for censorship circumventing meshes is to use whatever means possible to establish a routing fabric that gives anonymity and prevent authorities from tracking down or shutting of specific people.

It's perfectly fine in that case to route over mobile internet, over cable or ADSL connections, or over Wifi or any combination.

Your work seems to focus on a particular subset where someone for some reason have decided to go entirely wireless. But that makes little sense, not least because it means the network becomes entirely insular. Most network will want uplinks/downlinks to the internet, and the moment you spread such links through the mesh, most of your issues fall away, as it, for example, becomes ok or even advantageous to design the system to break wireless links and have the topology rearrange regularly and part of the routing could be to negotiate splitting and changing wireless links to break the wireless networks into smaller, but constantly changing chunks.

Your concern about omnidirectional networks swamping each other is similarly contingent on an all-wireless mesh, and a fairly dense one at that. I'm sure there are places where it is an issue, but I live in an substantially above averagely dense area, and I count about 10 wireless devices in my living room. I can detect about 5 other wireless networks around me, none on competing channels. If I bridged my network to two of those five, it would not substantially increase the amount of contention, especially as I know from measuring that several channels in normal wifi range are not used by any of my nearby neighbours, and given that I can compare to work, where we have 20+ computers with their own wifi networks on in the same room, paired with 20+ phones, and 10+ other large office networks visible.

Yes, the bandwidth to the internet would be low if we all were to try to piggyback off one uplink, but that would be silly. Instead, a proper privacy / censorship enhancing mesh would try to pass the traffic peer to peer where possible, and hand off parts of all the traffic to our upstream internet connections via encrypted connections to other parts of the mesh too.

When it comes to equipment, I have several wifi devices that fit inside a USB plug. Their antennas are not great, but easy to improve, so the idea that it'd be easy to prevent sales of suitable equipment is unlikely, I think - A USB hub plus a bunch of cheap USB wifi units + a $40 small computer, and you can bridge heaps of networks. In a situation with active censorship, there are enough consumer equipment that is trivial to create ad-hoc routers from, even if you worst case have to hook a bunch of bulky wifi access points together.

In fact, the possible units are cheap enough that I've been toying with the idea of bridging my own wifi along the 2 miles or so from my house to the train station I commute from by strategically hiding small android computers with an extra wifi interface, mostly for fun. The limiting factor now is no longer cost, but solving the power issue (finding a unit low enough power to be able to supply it via solar (I don't fancy the increased risk of trying to steak power anywhere along the route, though there's plenty of poorly protected tempting telco cabinets that'd be ideal) without making the units big enough that it'd be too hard to hide units along the road without having bomb squads called out...).

Routing protocols for large meshes certainly are still an issue, but that issue will only be solved if we actually try. And again it is worth keeping in mind goals. if your goal is to replace the public internet, then it's hard, as the bandwidth and latency requirements become a big challenge. If the goal is evading censorship, then you only need to pass certain traffic over the mesh fabric. In fact, the smaller percentage, the better, as much of the traffic will need to exit somewhere to bridge air gaps, and the smaller the traffic, the easier it will be to traffic mix and hide any encrypted exit traffic.

Re: Mesh Networks

#98
post #91

http://www.nytimes.com/2011/06/12/world/12internet.html?page... For best UX, set your "Referrer:" header to google.com Also, I think Cisco paid over a billion for one mesh community network's project. I think a YC cofounder may have been involved in that project. Not sure. Its Cisco brand name is Meraki. It appears portable autonomous networks (i.e. no telco needed) are useful and valuable for many, diverse reasons.…

Also, I think Cisco paid over a billion for one mesh community network's project.

Meraki was worth $1B because they almost completely pivoted away from mesh towards more conventional networking.

Re: Mesh Networks

#99
post #53

Earlier quoted context omitted.

Before they radically changed direction and were acquired by Cisco, Meraki tried to target community meshes in SF and beforehand as Roofnet at MIT. They handed out/sold a lot of mesh APs. I wonder what happened to the boxes.

Several hundred roofnet devices were distributed to low-income housing in the South End and Roxbury neighborhoods of Boston. The networks are still limping along with some volunteer maintenance. There are some really dedicated people working to provide for some of the technology needs of the communities, such as free computer repair and training. Check out http://cstoboston.org/ http://www.tech-center-enlightentcity.…

Great to hear. Is someone making compatible hardware/software that interoperates?

Re: Mesh Networks

#100
There's just a lot that has to be rethought for mesh networks to work as "show up with an antenna and you're on the internet/ are the internet". IP layer, I'm looking at you.

I remember being told about research being done on multi-core processing in the 70's, but no headway there could outpace the standard of shrinking the technology and increasing the clock rate. Now we may as well assume n-cores. It's my hope (because mesh networks sound way more democratized and just "seem" like the next logical way of scaling the internet) that antennas become cheaper at a faster rate than wired infrastructure (given the fairly inelastic cost of digging shit up) and mesh networks start to make sense.

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