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Build a Wireless ISP on Linux
JuiceMan wrote to mention an article that goes into the the specifics of setting up a Wireless Internet Service Provider (WISP) using Linux and a few easy scripts. From the article: "Wireless clients will have questions, and the Linux-based management tools I'll discuss will help you answer them. Here are some quick examples of how you can answer typical user questions - Question: 'Is the Internet down today? Why can't my browser find www.flakyhost.com?' Solution: First, check your wireless network with the scanap script; it will tell you about the wireless signal quality of all associated clients, including the one that's giving you problems. Then, check IP connectivity with the pingall script; it will tell you about the latency to your ISP's gateway, the DNS, and all your clients, including the problematic one. If these two scripts establish that your network is OK, try www.flakyhost.com."
For a WISP, it's a different story than for a wired line ISP. A WISP only has so much bandwidth for a given frequency whereas a wired line ISP can keep adding massive bandwidth. In order to make a tower site cost-effective, "overselling" the bandwidth is the only way to go at low cost consumer prices. The law of averages says that at any one time, not everyone will be pulling data.
If someone resells to their neighbors, then they will be more likely to peg their bandwidth slice all the time. As someone else made mention, it isn't a big deal if it is a commercial account because the WISP probably charges a premium for a CIR on the bandwidth as opposed to charging a minimum for a consumer MIR.
CIR = Confirmed information rate (guaranteed bandwidth)
MIR = Minimum information rate (best effort bandwidth)
Starting yesterday (Sunday), Staples is selling the Linksys BEFW11S4 802.11b AP/router (w/ 4-port switch) for $9.94. Linksys 802.11b Cardbus adapters are now $4.94. Please note these items are 802.11b only. (I imagine they are trying to clear out the older gear.) These prices are for in-store purchases only. I picked up a couple of each for spares - in a pinch 802.11b is 802.11better_than_nothing.
I'm not affiliated with Staples or Linksys except as a customer.
I want to drag this out as long as possible. Bring me my protractor.
While the WRT54G may make an acceptable client to a WISP network, running the WISP off one is asking for problems. For starters they get pretty toasty after a while and the processor can't handle the load of a larger network reliably. If your going to go all out and actually start your own ISP at least use a little common sense and purchase hardware designed for that purpose.
I run a slightly larger ISP than the article author, but he's really nailed the essence of it.
In the commercial world, you run carrier grade gear, with SNMP built into it, but I still have original (two+ year old customers) with WET-11 radios installed, and the author's script worked great.
The most important thing I've learned running a WISP is that people treat it like a utility. When they turn the tap, they expect water, when they flip the switch, they expect light, and when they click "Go", they expect the internet. As the WISP operator, the sooner you stop treating it as a hobby and start treating your service like a utility, the longer you'll keep happy customers. Automating checks and finding problems before they occur is exactly how to do that.
WET-11s usually fail in two stages, with Stage 1 being a gradual degredation of packet success rate, usually after a "close" (1/4 mile) lighting strike. Stage 2 takes about 4 weeks to reach,and it's total failure. The sooner you catch the degredation, the faster you can respond and keep your customers happy. The article author's scripts aren't too hard to extend and automate to make that happen.
John Gorkos
Wildcat Wireless ISP
DeSoto, KS
I doubt such an ISP allows reselling of bandwidth. No consumer-grade service allows this in the TOS, a carrier grade connection is required because, as the previous poster noted, you are reselling an oversold connection. A carrier grade connection is a guaranteed bandwidth connection, meaning not oversold.
A lot of the reason the first ISP in question is expensive is because they have to buy a carrier grade connection and resell that, and it basically cannibalizes their ability to pay for the carrier connection.
Besides, undercutting the competition using that competition's service, without paying for the rights to do so isn't a fair thing to do, as I noted above, it's actually being parasitic. The fair thing to do would be to buy a proper carrier connection, then resell it.
You can use arping to debug WinXP. Machines have to respond to arp or they can't get their network traffic.
The best way to build a WISP with a WRT54G is using the Freifunk Firmware (based on openwrt.org) which builds a routed mesh network with any WRT54G flashed with the same firmware. It is really simple and totally open and free - unlike the Sveasoft weenies. Some howtos on my blog:
How to setup OLSR (a mesh protocol) with Freifunk firmware on a WRT54G
Sharing broadband with a WRT54G
Really simple antennas for the WRT54G
Less Networks have a bootable cd that serves as a wi-fi hotspot server, which takes care of virtually all the hassle. If you are not going to be charging for access, then it's ideal. Forces a re-login every so often IIRC. Runs fine on a P2 with 128Mb RAM. You do need 2 nics (one in, one out) and an access point of course.