Re: [IAEP] Mesh Dreams = OLSR
Mike, Thank you for the information! To be clear, from what I understand from our discussions in the past you're topology looks like AP(802.11A + OLSRD) - AP (802.11B/G) - XO You have several AP(802.11A + OLSRD) acting as your backbone and they drop down to standard AP (802.11B/G) for connection to the XOs. Please let me know if this is correct. Out of curiosity: have you considered extending your OLSR network to the AP (802.11B/G)'s and installing the OLRSd binary on your XOs so the OLSR network can be extended beyond the school? Thanks, Reuben On Sep 2, 2010, at 6:36 PM, Mike Dawson wrote: Hi, Sorry for my late reply to this. Actually we use OLSR in Afghanistan to do our school networking like so: 1. An OLSR router (running openwrt Freifunk ; see freifunk.net ) connects to the other routers in the school - that forms the backbone on one network (e.g. channel 6) 2. A vanilla OpenWRT router actually connects to the XOs in the class. We reduce the transmit power on that and run it on a different channel (e.g. 1 or 11) The plus side is that you get a pure wireless system that does not need network cabling / does not have cables getting killed by the environment. The down side is you use more routers. I think financially the costs are pretty similar. Also you can now use 802.11n to get good speeds on the backbone. Seems to scale pretty nicely - we have 500 XOs in most schools. Note though by design we are not using the collaboration on the school server but rather just through the AP - teachers are not that enthused by the prospect of kids being able to chat with anyone anytime. This has practically made doing the deployment in the field a bit easier - though the firmware is not always perfect and not always working out of the box with all hardware options. Regards, -Mike On 25/08/2010, Martin Langhoff martin.langh...@gmail.com wrote: On Tue, Aug 24, 2010 at 11:13 AM, Reuben K. Caron reu...@laptop.org wrote: Where Mesh != 802.11s but rather an adhoc, self healing, self organizing routable network. Cerebro gave a great working demo of what you describe. Don't know how they compare. I think it is perfectly feasible to achieve what you want... - to do it seamlessly and with polish will take a ton of work - very few users will actually benefit because the under a tree scenario covers IMHO most of our interesting use cases. People do talk about having a mesh that covers their whole town, and it's great dream but not achievable with our current constraints - town-wide meshes are made of stationary nodes - the mesh approaches we're discussing burn CPU / battery... - perennially power-starved users will focus on use, not on maintaining the communal mesh up Imagine a world where Sugar on a Stick machines can communicate on the same network as an XO laptop We have that now with ad-hoc and infra. Limited but we have it. A world where mesh capabilities are hardware agnostic allowing anyone to bring up a mesh network by booting a live cd. Mesh is pixie dust for most people. Your 'imagine' lines will make the imagine things that cannot be made to work _in the way people imagine_. Some meshy things can be made to work in a lab. Others just involve tradeoffs no sane user would take on... We've had bazillion threads about this, because mesh stokes passion. Problem is... even if you had the magical code right now working seamlessly... the cost/benefit ratio isn't good. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [IAEP] Mesh Dreams = OLSR
Hi Reuben, It's AP(802.11N + OLSRD) AP(802.11B/G) - XO - that's it as it is... Actually considered putting up routers outside the school to try and form a cloud that would then link back to the school / library. Haven't yet considered putting that on the XOs - we would need to put some logic on them like if I'm connected / or see the network school function as normal if not then run OLSRd. Then we could put routers w/panels up lamp posts, trees, etc. Would be nice to do - actually have had reports of quite large mesh accomplishments being done relatively densely with OLSR because it keeps it's own table of routes in the normal memory. Unfortunately at the moment we would lack the development manpower to actually put that into practice. In theory would just be putting a script of some kind in the if-up section. Regards, -Mike On 03/09/2010, Reuben K. Caron reu...@laptop.org wrote: Mike, Thank you for the information! To be clear, from what I understand from our discussions in the past you're topology looks like AP(802.11A + OLSRD) - AP (802.11B/G) - XO You have several AP(802.11A + OLSRD) acting as your backbone and they drop down to standard AP (802.11B/G) for connection to the XOs. Please let me know if this is correct. Out of curiosity: have you considered extending your OLSR network to the AP (802.11B/G)'s and installing the OLRSd binary on your XOs so the OLSR network can be extended beyond the school? Thanks, Reuben On Sep 2, 2010, at 6:36 PM, Mike Dawson wrote: Hi, Sorry for my late reply to this. Actually we use OLSR in Afghanistan to do our school networking like so: 1. An OLSR router (running openwrt Freifunk ; see freifunk.net ) connects to the other routers in the school - that forms the backbone on one network (e.g. channel 6) 2. A vanilla OpenWRT router actually connects to the XOs in the class. We reduce the transmit power on that and run it on a different channel (e.g. 1 or 11) The plus side is that you get a pure wireless system that does not need network cabling / does not have cables getting killed by the environment. The down side is you use more routers. I think financially the costs are pretty similar. Also you can now use 802.11n to get good speeds on the backbone. Seems to scale pretty nicely - we have 500 XOs in most schools. Note though by design we are not using the collaboration on the school server but rather just through the AP - teachers are not that enthused by the prospect of kids being able to chat with anyone anytime. This has practically made doing the deployment in the field a bit easier - though the firmware is not always perfect and not always working out of the box with all hardware options. Regards, -Mike On 25/08/2010, Martin Langhoff martin.langh...@gmail.com wrote: On Tue, Aug 24, 2010 at 11:13 AM, Reuben K. Caron reu...@laptop.org wrote: Where Mesh != 802.11s but rather an adhoc, self healing, self organizing routable network. Cerebro gave a great working demo of what you describe. Don't know how they compare. I think it is perfectly feasible to achieve what you want... - to do it seamlessly and with polish will take a ton of work - very few users will actually benefit because the under a tree scenario covers IMHO most of our interesting use cases. People do talk about having a mesh that covers their whole town, and it's great dream but not achievable with our current constraints - town-wide meshes are made of stationary nodes - the mesh approaches we're discussing burn CPU / battery... - perennially power-starved users will focus on use, not on maintaining the communal mesh up Imagine a world where Sugar on a Stick machines can communicate on the same network as an XO laptop We have that now with ad-hoc and infra. Limited but we have it. A world where mesh capabilities are hardware agnostic allowing anyone to bring up a mesh network by booting a live cd. Mesh is pixie dust for most people. Your 'imagine' lines will make the imagine things that cannot be made to work _in the way people imagine_. Some meshy things can be made to work in a lab. Others just involve tradeoffs no sane user would take on... We've had bazillion threads about this, because mesh stokes passion. Problem is... even if you had the magical code right now working seamlessly... the cost/benefit ratio isn't good. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [IAEP] Mesh Dreams = OLSR
I'm not 100% certain we've pulled in members of the OLSR mailing lists on this thread yet. But they've actually got a number of very impressive *real world* demonstrations of OLSRd in the wild. You'll have to search the devel@ archives for 'olsr' to find the emails I sent years ago with all the details. Granted, I don't know that they've demonstrated the software scaling out to distributed notes *and* in to 100 laptops in a single room w/o any manual tweaking. They can best tell you about that themselves. But OLSR is a much more appropriate and much less pixie dust solution than 802.11s ever was/is/will be. I think the primary challenge is social -- isn't it always? The OLSRd guys have to get passionate about making their stuff work on XOs, and enough deployments have to be adventuresome (and desperate) enough to give them a testbed to iron out all the kinks. But I think it's a worthwhile management challenge for someone to attempt. Because what's needed is leadership, managing the resources, linking person A to person B, driving it to release/ship, and a little bit of inspiring the troops. The technical challenges are much less hard. (And it's probably an outside OLPC project, at least initially, because OLPC can't afford to devote any resources to it.) --scott ps. technical challenges: making it bulletproof and brainless, seamless scalability from lots of laptops in a tight space to a few laptops spread out, and (eventually) processor-independent operation on the marvel microcontroller to allow sustaining the mesh at very low power levels. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [IAEP] Mesh Dreams = OLSR
Hi, Sorry for my late reply to this. Actually we use OLSR in Afghanistan to do our school networking like so: 1. An OLSR router (running openwrt Freifunk ; see freifunk.net ) connects to the other routers in the school - that forms the backbone on one network (e.g. channel 6) 2. A vanilla OpenWRT router actually connects to the XOs in the class. We reduce the transmit power on that and run it on a different channel (e.g. 1 or 11) The plus side is that you get a pure wireless system that does not need network cabling / does not have cables getting killed by the environment. The down side is you use more routers. I think financially the costs are pretty similar. Also you can now use 802.11n to get good speeds on the backbone. Seems to scale pretty nicely - we have 500 XOs in most schools. Note though by design we are not using the collaboration on the school server but rather just through the AP - teachers are not that enthused by the prospect of kids being able to chat with anyone anytime. This has practically made doing the deployment in the field a bit easier - though the firmware is not always perfect and not always working out of the box with all hardware options. Regards, -Mike On 25/08/2010, Martin Langhoff martin.langh...@gmail.com wrote: On Tue, Aug 24, 2010 at 11:13 AM, Reuben K. Caron reu...@laptop.org wrote: Where Mesh != 802.11s but rather an adhoc, self healing, self organizing routable network. Cerebro gave a great working demo of what you describe. Don't know how they compare. I think it is perfectly feasible to achieve what you want... - to do it seamlessly and with polish will take a ton of work - very few users will actually benefit because the under a tree scenario covers IMHO most of our interesting use cases. People do talk about having a mesh that covers their whole town, and it's great dream but not achievable with our current constraints - town-wide meshes are made of stationary nodes - the mesh approaches we're discussing burn CPU / battery... - perennially power-starved users will focus on use, not on maintaining the communal mesh up Imagine a world where Sugar on a Stick machines can communicate on the same network as an XO laptop We have that now with ad-hoc and infra. Limited but we have it. A world where mesh capabilities are hardware agnostic allowing anyone to bring up a mesh network by booting a live cd. Mesh is pixie dust for most people. Your 'imagine' lines will make the imagine things that cannot be made to work _in the way people imagine_. Some meshy things can be made to work in a lab. Others just involve tradeoffs no sane user would take on... We've had bazillion threads about this, because mesh stokes passion. Problem is... even if you had the magical code right now working seamlessly... the cost/benefit ratio isn't good. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [IAEP] Mesh Dreams = OLSR
On Tue, Aug 24, 2010 at 11:13 AM, Reuben K. Caron reu...@laptop.org wrote: Where Mesh != 802.11s but rather an adhoc, self healing, self organizing routable network. Cerebro gave a great working demo of what you describe. Don't know how they compare. I think it is perfectly feasible to achieve what you want... - to do it seamlessly and with polish will take a ton of work - very few users will actually benefit because the under a tree scenario covers IMHO most of our interesting use cases. People do talk about having a mesh that covers their whole town, and it's great dream but not achievable with our current constraints - town-wide meshes are made of stationary nodes - the mesh approaches we're discussing burn CPU / battery... - perennially power-starved users will focus on use, not on maintaining the communal mesh up Imagine a world where Sugar on a Stick machines can communicate on the same network as an XO laptop We have that now with ad-hoc and infra. Limited but we have it. A world where mesh capabilities are hardware agnostic allowing anyone to bring up a mesh network by booting a live cd. Mesh is pixie dust for most people. Your 'imagine' lines will make the imagine things that cannot be made to work _in the way people imagine_. Some meshy things can be made to work in a lab. Others just involve tradeoffs no sane user would take on... We've had bazillion threads about this, because mesh stokes passion. Problem is... even if you had the magical code right now working seamlessly... the cost/benefit ratio isn't good. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [IAEP] Mesh Dreams = OLSR
On Tuesday, August 24, 2010 11:26:23 am Chris Ball wrote: Hi Reuben, Consider the benefits of using open source software versus our closed source firmware and partnering with communities like Freifunk whose network is ~ 800 node, guifi.net is almost 10k nodes in Barcelona, Athens Wireless is 5k nodes. The fact that a custom mesh algorithm would have to run on the CPU -- prohibiting any kind of idle-suspend -- makes it a non-starter for an XO deployment in my eyes. Did you have any thoughts on this? We (MontevideoLibre, a free wireless community network) have been using OLSR for a while now. And though the topology in a typical OLPC scenario is very different, we've talked about assembling an image running OLSRd for a while. Anyway, I dont have time for a full response to this thread right now, but I had a conversation with smithbone and silbe a while back that may be illustrative of the worse-case scenario in terms of power consumption: aasilbe: I think a working PoC could gather a lot interest from deployments... silbe aa: one thing to consider is the power draw. with libertas_tf, the host CPU needs to be powered on. aayes aasilbe: do you have an idea of what that means in actual numbers? aaperhaps smithbone has a guesstimate silbe aa: counter-question: are you thinking of running the protocol while the XO is powered off (screen off, everything in suspend with wake-on-WLAN) or just during regular operation? silbe for the latter case, it might not make much of a difference, especially if automatic power management (automatic suspend) is disabled. smithbone Running the system is going to cost you in the 5W range. silbe in the powered off case it's going to make a huge difference. I don't think it'll be able to run for more than 3h while there's any traffic. aasilbe: one of the things I want to find out is the convergence time of the different options silbe aa: i.e. the time until the network/mesh is stable? aayes silbe aa: if you were in europe, you might try getting funding from the EU for that ;) aasilbe: also, BATMAN has a layer 2 kernel module, maybe we could make it aware of the PM state? silbe they seem to pay some pretty sums for mesh research * aa migrates to Europe aa:P silbe aa: it should just integrate into the kernel PM QoS framework I cuppose, see Documentation/power/pm_qos_interface.txt aasilbe: will do silbe aa: oh, and some recent mail from me has a link to nice slides explaining the PM QoS framework aasilbe, smithbone: do you guys know if wol would work with libertas_tf? aasilbe: to sugar-devel? silbe aa: no idea, sorry. silbe aa: I think to de...@l.l.o aasilbe: found it, thanks! smithbone aa: which gen? aasmithbone: XO-1 smithbone aa: on XO-1 the wakeup is generated by strobing a signal to the EC. So libertas_tf would need to support strobing that signal aasmithbone: thanks a lot, is this documented somewhere? aatoo bad the firmware is closed :( smithbone aa: no. because none of the systems you are talking about have open documentation aasmithbone: I understand smithbone aa: But I can certainly tell someone what gpio on the wlan module to strobe and for how long. -- -Andrés signature.asc Description: This is a digitally signed message part. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel