Hybrid Community Networks? 23
CaryMenage asks: "I live in Philadelphia where there is a chock full of row houses and MDU (Multiple Dwelling Units) buildings. I was wondering if other Slashdot readers have been involved with community networks and what methods they have used. I have been looking at several different ways to distribute a T1 circuit to multiple end users; WiFi, Powerline, HomePNA. Due to the physical and legal complexities of older buildings and crossing public streets, I feel that some type of hybrid mixture of different topologies would work well in many situations. Has anyone implemented any of this on a large scale installation?"
"I currently let my neighbor access the Internet through a powerline device that works well through the power meters. It seems to me that in theory, one could repeat the Ethernet with a cheap switch and send it to the next neighbor with another pair of powerline devices. Then when you have to cross a public street one could use a pair of Wireless Access Points in bridge mode. I also found a "leaky coax" product called RADIAX that I was wondering if anyone has applied this to 802.11. Seems to me you could use this coax and amplifiers to expand wireless coverage within buildings. For apartment buildings with somewhat organized main phone closets I have been looking at HomePNA products like the Xterasys HSM-1402 14-port HomePNA Switch and the Xterasys VX-110B for the end users connection."
Limited physical change (Score:3, Interesting)
wireless routing (Score:3, Interesting)
For a large wireless network, you'll probably want a robust ad-hoc routing protocol [wikipedia.org] like aodv or dsr. Most cheap wireless access points don't support that sort of thing, though. Take a look at roofnet [mit.edu] if you want to see what's possible. This is still an active area of research, though. Any success stories out there about large wireless ad-hoc networks?
-jim
Re:Limited physical change (Score:3, Informative)
Re:Limited physical change (Score:3, Interesting)
For something thats more or less a perm network structure, generally one way to do it is with older cheap boxes (IE p133's) that you can get say 4 of. (Two sets of two, one for each side of the bridge, and redundancy)
Throw in a wireless card, hookup your directional antennas, and run without WAP but use IPSEC over the two. Even simplier (But not as flexible or secure, the later of which is all that may be importaint here) is another simpler e
Why? (Score:2)
Re:Why? (Score:2)
T1 also uploads much faster, which will be a factor if you have a few gamers or a few people that VPN all the time, or both.
T1 also usually comes with static ip addresses which would be handy if you have users that want to run dedicated servers, like a website for the apartment building. Sure you can host on cable mo
Re:Why? (Score:1)
Re:Why? (Score:2)
Re:Why? (Score:2)
Similar to rural wireless networks. (Score:1)
www.gorge.net
Fiber? (Score:4, Informative)
Fiber optic networking is great technology, and its not that expensive to get old fiber optic ethernet to coper ethernet media converters (typically ~$150 for 100mbps multimode, ~$200 for 100mbps singlemode). On ebay such equipment is much cheaper, especially if you go with old 10mbps 10baseFL media converters.
If laying your own cable is an option, this would give you a great upgrade path. 10mbps now, 10gbps in a few years.
The big choice is singlemode or multimode. Single mode equipment is harder to find and a little bit more expensive. The range (20-100 km for SM, 2km for MM) and theoretical information capacity (terabits per second vs gigabits) is much greater, though. I've heard that SM is harder to terminate unless you can afford a fusion splicer.
Has anyone out there inexpensively set up a community network with fiber?
-jim
Go All Wireless (Score:5, Interesting)
I used a couple of old junker laptops running Linux. This should be completely scalable to your situation. Here's a link [hrp.com] to how I did it. For a relay/access point the same principle applies, just use two cards, one with a directional antenna the links to you, the other with an omnidirectional that serves DHCP. I found that cheapo cards on old hardware works great.
There are plenty of sites that have intructions for building directional antennas. From my experience you don't need to spend a lot of money for this kind of thing.
I'm glad your sharing your bandwidth. More people need to do this. Hopefully, one day the Internet will be entirely wireless and free. Free meaning you don't have to pay an ISP, you just buy your equipment and you're online. Just like CB radio.
Feel free to use my email address at the above site if you have any questions.
Re:Go All Wireless (Score:1)
Re:Go All Wireless (Score:2)
Re:Go All Wireless (Score:4, Interesting)
First, the questions:
What kind of security plans do you have? Is this to be firewalled from the Internet but an open LAN behind the firewall? Will each building/unit have a firewall?
How large an area are you looking at servicing? One street (both sides)? Two? A city block?
Are you setting up your own servers/services: Web hosting, e-mail, etc? Will everyone receive a live IP, or will it be private?
Next, some thoughts.
I would suggest firewalls. Sure, it's a pain - and an expense - to install at every unit, but it ensures security. If one of your users puts in an unsecured WAP, you aren't vulnerable. I would at least suggest it to each user. If they want to join the "network neighborhood", so be it. A $50 Cable/DSL Router should work splendidly, and transition to other services if a user desires.
Wireless is great for a dozen reasons; the biggest is convenience. If you do install wireless, I would recommend that the access points are 802.11g and support wireless bridging. The extra expense means no extra cables and the ability to expand the network quickly. You might also look into using directional antennas [cantenna.com] if you just want to bridge a distance. The directional antennas give you much better range and make it slightly more difficult for others to access your network. Encryption should go without saying. You might also consider setting up separate 802.11b base stations if there are many laptop users. 11b users will slow down an 11g access point.
For in-home wiring, it might be preferable to design a common "wiring cabinet" that you can tuck in a corner of the basement or mount on a wall. You can fabricate them identically and drop them into each house with a cheap eight-port switch, a surge protector with a swiveling plug (you have no idea how nice these are until you have one) and a little extra space for firewall/router, more switches, etc. to make installation a breeze.
You might think about a secondary Internet connection and a dual-wan router [xincom.com] to improve speed and reliability of the connection. The expense isn't huge and additional bandwidth never killed anyone.
Re:Go All Wireless (Score:2, Informative)
Another Topology Method (Score:4, Interesting)
Re:Another Topology Method (Score:1)
Cat5 all the way baby. (Score:5, Interesting)
See http://www.era.ro/ for an example.
There are almost 100 networks like this here in Bucharest.
Re:Cat5 all the way baby. (Score:2)
When it comes to wiring Cat5 outdoors, or between buildings, there are some VERY important bits of knowledge you need:
http://volker.top.geek.nz/linux/tech/outdoorwirin
It is possible to end up making your PC chassis live due to a wiring fault and running Cat5 to your neighbours.
Nick
Optical Air Link (Score:4, Interesting)
Here some links:
Home page [twibright.com]
Some 64 existing deployments of the device [twibright.com]
An example of installation in dense city area [twibright.com]