Pretoria community wireless network

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phazer_

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Anyone have details about the Freenet guys?

I am thinking of putting up a wireless node using the Jawug kit (http://www.jawug.za.net/JawugKit).

Perhaps over time try to get Pretoria to be connected to the Jawug mesh.

Who would be interested in setting up a Pta mesh? If enough people we can setup a website (I can do hosting) and maybe start a Pawug :D

I am based in Lynnwood ridge close-ish to the CSIR and Menlyn shopping centre.
 
I'm definitely interested! Also had a look a the JawugKit. I'm located in the Southern most part of Centurion at the moment.
 
Count me in.. I'm definetly available to help as much as possible.

Currently staying in Faerie Glen, next to Pick 'n Pay

:)
 
First things to do, is to go register yourselves on nodedb.com. That way you can start planning the interconnects.
 
Located in RietvalleiRand

I am located in Rietvalleirand, although our business operates from the CSIR buildings in Lynnwood. wanna connect there?
 
Im keen. My location is Hatfield, Pretoria. Im trying to arrange a linkup to the varsity. There is a bunch of reasons why this would be useful..
I see nodedb is down. Anyways, we have a couple of guys already on a mailing list of sorts for a pretoria wireless group. Can you send me the details of your mailing list etc and I will merge everyone..

Now to get some proper wireless kit. Gonna be a bugger since Im in a building-dense area. Still debating which is better - omni or directional. Not sure where I would point a directional yet :p
 
directional!!

I think directional for linkups, omni for local.
You can have both with these modems that split the signal....
And you can split the signal with splitters, just like TV cable.
Would you like us to source equipment for you?
 
Do not split the signal.
End of story.

Do a little research on the "Hidden node problem" that is inherent to long distance point-to-multipoint systems.
Also do a little bit of research on how splitting RF can cause some very nasty impedence mismatches.

Bottom line.. (same as the top line.. har har.. bad pun)
Do not split the signal.
 
respect

I know an idea did the rounds of having multiple radio's on the boxes (some upgrade?), so I thought a good alternative could be to split the signal.
But I'll take your word for it! Do you have a link to the article?
 
Hidden node solved by www.qorvus.com

Hidden node is solved by
www.qorvus.com and http://frottle.sourceforge.net
via the Token Ring protocol. Ethernet suffers from hidden node in a
wireless setup.
www.hyperlinktech.com sells wi-fi splitters than can split a signal into
four attached sector antennas. But a signal splitter halves the power, so on
a 4-way splitter a Prism 802.11b 200mw card will be reduced to 25mw
on each section. I believe impedance mismatch can be solved by using
exact length Lm-400 cable to each antenna.
Two parabolics back-to-back on a signal splitter functions in exactly the
same way as an Omni, only your signal is now two tight 8degree beams and you are not picking up 360degree interference. It is an ideal way to repeat a
signal since you are not introducing latency's . Alternativly you could intall
two Senao prism 802.11b cards in the PCI slots of a Mini-itx computer and purchase www.qorvus.com software for R600 per machine to setup a
wi-fi system than simply works. Wi-fi is incredibly complex as more users get added, my point is that there is no need to reinvent the wheel. Get www.qorvus.com software and get your project of the ground.

If only those morons at www.wavestream.co.za would use signal splitters we might not have a trashed 2.4ghz spectrum. Please whatever you do , don't
use Omni's , you are polluting the spectrum and degrading your network.

Let each client install a parabolic and aim it at a sector 60,90degree etc
antenna in either infrastructure mode or ad-hoc. Infrastructure is great if
you have a prominent high-site.
 
There are so many holes in that post, I dont know where to begin.

Sure, you can use frottle, but then you need the frottle client installed on every wireless client.

Yes, proper splitters are available, but that often defeats the whole purpose of having seperate sectors.
4 x 90 degree sectors = 360 degrees. Put them all on seperate radios, and you've achieved a number of things.
1) You can now support at least 4 times more throughput (without taking collisions into account)
2) Your collision domain is now a quarter of what it would have been, meaning less collisions (which also means, more actual throughput)
3) Noise recieved on one sector doesn't polute the signal on any of the other sectors, because they aren't actually connected together.

Qorvus have nothing on MikroTik. (MikroTik is slightly cheaper, has more features, been around longer, has better support, supports more hardware, etc)

Our fabulous friends at Wavestream do actually use signal splitters, and Amps. So they dont have to use as many radios, they do pickup noise from everywhere, and they amp that noise, and then rebroadcast it. I WILL PERSONALLY TRACK YOU DOWN AND BEAT YOU WITH A STICK IF YOU DO THIS!

Ad-hoc is great for mesh networks, but where possible, try to use Infrastructure.
I think TheRoDent did some playing around with ad-hoc on his long distance links, and found that infrastructure mode still worked better. Perhaps he can give a better explaination.
 
Mikrotik is good and is used on the outer nodes of mesh. www.qorvus.com software based on opensource www.locustworld.com mesh and incorporates frottle. Frottle is just one layer in this mesh software implementation of AODV routing protocol.
Jon Anderson from locustworld adapts the output power from the Senoa card on the
fly as each node relays data in his implementation of AODV.
The other option to www.qorvus.com is www.cuwireless.net which uses the Hazy routing protocol. The CPE's connect in infrastructure mode to the mesh node.
Client nodes will be WRT54G linksys AP's. Your mesh nodes are connected in Ad-hoc up
to a max of 3 or 4 nodes daisy chained, this mesh get's fed by a DSL or leased line or Transtel line.
Signal splitters are ideally not used to create more than on repeater node for ad-hoc
mesh nodes. A second Senao card rather is added to form a repeater.
Setting up just 4 repeaters with vanilla AP's reduces the signal by 1/16000.
With mesh it is 15% of each hop. So if you start with 11meg you are down to
3-5 meg at the fourth hop. If you can do with 1meg of bandwidth and your signal must go over a mountain, set up a two AP's one in master other one in slave each on a
different channel and connect them via cross-over ethernet.

By using Wi-Fi and Cat5 cable and www.aviosys.com ethernet camera module and a realtime Ogg-Vorbis Linux video compression box one can build a cost effective video surveillance systems for streets and business. www.qorvus.com quoted webcam prices are just to expensive. The aviosys.com ehternet cam module is sold by
www.miro.co.za. What I thought about is say one shop training a camera on the opposite shop and recording it any activity on a linux box. So a criminal would have to strike BOTH shops to get to the surveillance tapes. In a cris-crossing mesh each shop
could watch the other. If you have any better ideas let me know.

The next great hope for broadband video surveillance and wi-fi internet is to get
http://madwifi.sourceforge.net to release the Linux drivers for Atheros 5ghz chipset -- Ad-hoc mode and implement 5ghz Ad-hoc - the core of mesh routing - on www.cuwireless.net . WE are not there yet.
 
we already have a mailing list going. greedyflyza, if you could just post the subscription method here again pls :P join up, it's quite an effective means of communicating and sharing ideas.

next i think we need a site. so give us some things you'd like to see on the site ...
 
Also, we should decide on a name.

We can either go with PAWUG or something like PWP (Pretoria Wireless Project), which is a little softer on the non-techie ear ...
 
well, have a look at my web portal at www.airhive.net
I've got 1000+ links in the links section that are related..
also willing to host wireless user groups under forums and wiki sections.

If you're putting up a seperate web site, I suppose its good to have a forum and Wiki sections.
 
malec said:
Also, we should decide on a name.

We can either go with PAWUG or something like PWP (Pretoria Wireless Project), which is a little softer on the non-techie ear ...
Click to expand...

How about using Tshwane (TAWUG) instead of Pretoria? I think Tshwane includes both Pretoria and Centurion if I'm not mistaken.
 
TAWUG = more PC, given the recent stink in the newspapers...
 
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