I am cc'ing Martin Langhoff, John Watlington who are in charge of the School Server at OLPC
> 1. ideally the school server (running XS) will have 3 active antenna > each running on a diff channel (1,3,6) and XOs will connect to one of > these. >2. Or should we replace the WRT54G with > another AP/Router in the short term? I would replace the WRT54G. I hate them. I have had 3 fail on me in the last year. I would get 3 other wireless routers. I like DLink My understanding is that in a dense deployment such as yours you should use a regular wireless router and not the active antennas, for the short and the long term. Wad and Michailis, pls correct me if I am wrong. >3. Running ejabberd on a central server means that collaboration > features will work while the XOs are connected to an AP (or school > server with active antenna)? The only change we need to make on the XOs > is to support this, is to change the jabber server using > sugar-control-panel? Correct >4. Can we expect to get around 50 XOs per channel? Don't know, sounds good to me. We are planning 60 XO's per channel w/ a Deliberant Radio + Omni 12 dbi antenna (Dev can provide more details) Wad, Michailis can you advise? > 6. Are the specs here for the hardware of a server here still current : > http://wiki.laptop.org/go/XSX_Server_Implementation I don't know about this. We are using different specs in Nepal 1.8 GHz Intel Core duo 1 GB of RAM 120 GB Hard drive We have a souped up XS because we intend to use Moodle and Mediawiki extensively. >Currently the only hardware we > have to run XS would be one of the XOs or an old IBM/Panasonic laptop > (PIII800) This might work for basic networking services but not any content management stuff. It might also get bogged down when running Squid. You should join server-devel mailing list to keep on top of XS testing and development. http://lists.laptop.org/listinfo/server-devel Good luck! Bryan OLE Nepal Kathmandu On Fri, 2008-03-28 at 14:24 +1100, matt wolstencroft wrote: > Hi, > Many thanks for all your responses. Before I answer your queries, I just > want to clarify a few points : > > 1. I have taken another look at the server docs and my understanding is > that ideally the school server (running XS) will have 3 active antenna > each running on a diff channel (1,3,6) and XOs will connect to one of > these. Other wireless equipment would connect to a sep standard wireless > AP connected to the server. The server is then connected to the WAN > modem and acts as router, firewall and DHCP for the 3 networks. Is this > a correct summary of the ideal situation? > > 2. Without any active antenna, would a short term solution be to use a > standard AP and connect it to our WRT54G (with wireless disabled on > this)? Once we have a stable XS server we can remove the WRT54G and > connect the AP to the server? Or should we replace the WRT54G with > another AP/Router in the short term? > > 3. Running ejabberd on a central server means that collaboration > features will work while the XOs are connected to an AP (or school > server with active antenna)? The only change we need to make on the XOs > is to support this, is to change the jabber server using > sugar-control-panel? > > 4. Can we expect to get around 50 XOs per channel? > > 5. Would you recommend the use of an XO as school server and if so how > many clients would you say it would support? > > 6. Are the specs here for the hardware of a server here still current : > http://wiki.laptop.org/go/XSX_Server_Implementation > > In response to your queries : > > > Do you have a server (e.g. school server) in place? > > We do not currently have a school server in place. As an interim we have > been using an XO with lighttpd and an rsyncd running. This was just a > quick way to allow us to distribute files to the XOs and backup up the > olpc home directories prior to updating the laptops. The long term plan > is to have a server in place running XS. Currently the only hardware we > have to run XS would be one of the XOs or an old IBM/Panasonic laptop > (PIII800) > > > Minimum requirements? > > - network needs to support existing IBM/panasonic laptops used by > teachers and students (for certain apps that are not currently running > on the XOs e.g. dyned). These have pcmcia orinoco 802.11b silver cards > - students need internet connectivity > - XO backups > - proxy with filtering capability > - DHCP > - DNS > - firewall/router > - ability to power external antenna for remote sites > > > Time frames? > > The deadline given to me by the school administrator for having basic > network services provided and an outline for a long term solution is the > 11th April. It would be good to have a working wireless network as soon > as possible though, however I am not sure when funds will be available > for new equipment. > > Thanks again for your invaluable help, > > Regards > Matt > > On Thu, 27 Mar 2008 08:06:20 -0400, "Greg Smith (gregmsmi)" > <[EMAIL PROTECTED]> said: > > Hi Matt, (Bryan or Sulochan, please see questions for you below), > > > > Sorry we didn't get you an answer before this but thanks for reaching > > out and following up! > > > > Do you have a server (e.g. school server) in place? > > > > We probably do not have a tested and approved wireless AP with router, > > firewall and DHCP. The original idea was that routing, firewall and > > DHCP are done on the server. > > > > That said we may be able to find someone to help test and qualify an AP > > with your requirements. > > > > You may want to focus on connectivity and defer mesh support until > > later. I know that mesh is a core application but there are some open > > issues with it right now. > > > > What is your time frame? > > > > If you come up with a list of absolutely must have minimum things you > > need done and a date, that helps focus everyone on getting you launched. > > Then we can add the next level of applications in a second pass. > > > > If we don't nail your answer by tomorrow AM US ET, I'll bring it up on > > the server and development lists to see if I can get more input. > > > > Bryan and Sulochan, > > > > I know its crunch time in the Himalayas but some input ASAP would be > > greatly appreciated for this roll out in Cambodia. > > > > What access point did you deploy? Do you have a suggestion for one that > > has a built in router? > > > > Are you going ahead with the mesh turned on or should we defer that? > > > > BTW congratulations on your success and thanks for all your great blogs, > > e-mail lists, forums and feedback (http://www.olenepal.org/)! It really > > helps other sites and helps focus development on real user needs. The > > fun part is just beginning :-) > > > > Thanks, > > > > Greg S > > > > > > -----Original Message----- > > From: matt wolstencroft [mailto:[EMAIL PROTECTED] > > Sent: Thursday, March 27, 2008 4:58 AM > > To: Greg Smith (gregmsmi) > > Subject: Fwd: Re: [laptop.org #8321] Questions about XO mesh networking > > > > Hi, > > I have been trying to find out from [EMAIL PROTECTED] what wireless router > > will be compatible with our 200 XOs after we found out that the WRT54Gv7 > > has problems due to WDS. So far I have had no response and my colleague > > Phillip gave me your email in the hope that you might be able to help. I > > have included the email history below to give you some context. > > > > Could you recommend a wireless AP with router, 2 antennas (pref rev > > tnc), compatible with 802.11g & 802.11b, stateful firewall, DHCP, 4 > > 10/100 LAN ports and costing around $100? The main criteria is that it > > does not have any problems with XO mesh networks. > > > > Any assistance would be greatly appreciated. > > > > Thanks, Matt > > > > > > -- > > Matt Wolstencroft > > [EMAIL PROTECTED] > > > > -- > > http://www.fastmail.fm - One of many happy users: > > http://www.fastmail.fm/docs/quotes.html > > > > ----- Original message ----- > > From: "matt wolstencroft" <[EMAIL PROTECTED]> > > To: [EMAIL PROTECTED] > > Date: Mon, 24 Mar 2008 20:19:49 +1100 > > Subject: Re: [laptop.org #8321] Questions about XO mesh networking > > > > Hi, > > Thanks for the quick response. I have a few more questions : > > > > 1. Will automatic MPP be turned on in future builds? > > > > 2. According to the OpenWrt website, the WRT54Gv7 cannot run the openwrt > > firmware. I just want to clarify that in this case we will have to > > replace the router? > > > > 3. The DLink equipment is just an AP. Could you recommend any wireless > > routers? Or is there a more up to date list than this : > > http://wiki.laptop.org/go/Wireless_Access_Point_Compatibility? > > > > Thanks very much for your help, > > Regards, > > Matt > > > > On Sun, 23 Mar 2008 20:01:45 -0400, [EMAIL PROTECTED] said: > > > On Sat Mar 22 01:44:19 2008, [EMAIL PROTECTED] wrote: > > > > Hi, > > > > I have just started working at Reaksmy school in Cambodia with 200 > > > > XOs (build 656). Access to the Internet is via a satellite which is > > > > connected to a linksys WRT54G v7 with the latest firmware > > (v7.00.4). > > > > The wireless configuration of the router is as follows : > > > > > > > > Channel : 11 > > > > Encryption : none > > > > Wireless SSID broadcast : enabled > > > > > > > > Documentation I have read suggests that the mesh networking should > > > > work in the following manner: > > > > > > > > - majority of XOs in the mesh act as mesh points : "uses its WiFi > > > > interface to both access the network itself and to relay traffic > > > > from other mesh points" > > > > - certain XOs will act as mesh portals (MPP): "connected to an > > > > external network, and that forward traffic in and out of the mesh" > > > > - an XO will associate itself with a mesh based on the following : > > > > > > 1. The laptop will issue a DHCP request, followed by a RREQ for a > > > > Mesh Portal anycast address and wait for RREP replies, on all > > three > > > > channels being proposed for OLPC meshes (1, 6, and 11) before > > making > > > > any decisions. > > > > 2. If any channel provides a lower hop count to a Mesh Portal, it > > is > > > > selected unless its signal strength is significantly lower. > > > > 3. If all channels provide the same hop count to a Mesh Portal, > > > > random selection is used. > > > > > > > > I have a few questions regarding the mesh networking and the > > > > configuration of the WRT54G: > > > > > > > > 1. Is automatic MPP turned off in build 656 and is it enabled as > > per: > > > > > > "http://wiki.laptop.org/go/Test_Config_Notes#Turn_on_MPP_Capability";? > > > It is turned off now and in all current builds. > > > > > > > 2. What are the determining factors that affect which XOs become > > > > mesh portals? > > > Every laptop that can see a AP can become a MPP if that functionality > > > is enabled. > > > > > > > 3. We have been seeing intermittent dropouts of connection to the AP > > > > > > forboth XOs and normal laptops. Are there any known problems with > > > > the WRT54G and the XOs? > > > From Michail Bletsas, in charge of connectivity: > > > "Using WDS frames for the mesh traffic turns out that it creates > > > serious interoperability problems with WDS-capable access points that > > > > > implement Dynamic establishment of links with other WDS peers (like > > > the ubiquitous Linksys WRT54 router/AP). We found that out during > > > field testing and it took several months to identify all the failure > > modes." > > > > > > So the answer to whether you should/can use WRT54Gx APs is "only if > > > you can upgrade them to an OpenWRT variant". "A good starting point > > > should be the DLINK DWL-2100AP which uses an Atheros Chipset." > > > > > > > > > > > > > > 4. Is there any recommended/tested firmware for the WRT54G v7? Is > > > > openwrt tested/supported? > > > > > > It has been tested by users, but no offical testing has been > > undergone. > > > Users report that OpenWRT does not have the problems of the original > > > firmware. > > > > 5. If we were to replace the WRT54G is there a list of preferred > > > > wireless equipment for OLPC systems? > > > > > > See answer to #3. > > > > > > > 6. Some documentation I have seen suggests that wireless APs should > > > > be configured to use channel 1,6 or 11. Is this still the case? > > > > > > > > > > > > > 7. If the steps listed above are correct then we should see XOs > > > > forming and connecting to mesh networks on channel 1,6,11 however > > > > they always seem to form a mesh on channel 1. Is this correct? > > > > > > XO's search all 3 mesh channels, looking for a school server running > > > on that mesh channel. When they don't see a school server on any of > > > the three channels, they connect to a serverless mesh on channel 1. > > > > > > > 8. Can XOs connected to different mesh networks currently see each > > > > other? > > > > > > No. Each mesh channel is a totally independent network running at a > > > different frequency. However, if there is a school server with > > > multiple antennas, it can route packets between the networks. > > > Therefore, if there is a school server with 3 mesh antennae, XO's can > > > use all 3 channels, and all see each other. > > > > > > > > > > > > > > 9. Our XOs can see the AP in the neighborhood view and when they > > > > connect to it, they become disconnected from the mesh network. Is > > > > this correct behavior? > > > > > > Yes. When MPP mode is disabled, an XO will only connect to either an > > > Access Point or a mesh > > > channel, but not both. > > > > Any assistance would be greatly appreciated. Thanks in advance, > > > > > > > > Matt Wolstencroft > > > > > > The above answeres were provided by Ben Schwartz (author of the > > > Distance activity), and the quotes were from Michail Bletsas. > > > > > > Keep in mind I am not an OLPC employee, I am a support volunteer. if > > > this does not answer your questions try [EMAIL PROTECTED], as it is > > > > > answered by OLPC staff. > > > -- > > > Thanks, > > > FFM > > > OLPC Support Volunteer > > -- > > Matt Wolstencroft > > [EMAIL PROTECTED] > > > > -- > > http://www.fastmail.fm - One of many happy users: > > http://www.fastmail.fm/docs/quotes.html > > > -- > Matt Wolstencroft > [EMAIL PROTECTED] > _______________________________________________ Server-devel mailing list [email protected] http://lists.laptop.org/listinfo/server-devel
