lanroamer.net · Domains · Slashdot Mirror

802.11b supports overlapping networks by Adam+J.+Richter · 2002-08-19 20:15 · Score: 5, Informative · on Starbucks Clashes With WiFi Hobbyists Over Airwaves

802.11b supports independent physically overlapping networks. Each network has a name (an "essid"). For example, if you had a network name "starbucks" and another named "free", and were using GNU/Linux, you could do:

iwconfig wlan0 mode Managed essid starbucks udhcpc --interface wlan0oriwconfig wlan0 mode Managed essid free udhcpc --interface wlan0

For more efficient transmission, you can even program your access points to use different frequencies. There are twelve overlapping frequency bands used 802.11b, which provide for three or four completely independent networks.

Attempting to associate with a network named "Any" or "" will usually result in associating the network with the strongest signal, depending on your driver and card. This is also true in other operating systems.

Perhaps it's more of a plug than a disclaimer, but I should mention I'm involved in LANRoamer, an open source system that you can use to sell passers-by access to your wireless network and other participating networks.

Allowed on my $50/month DSL line by Adam+J.+Richter · 2002-04-01 00:33 · Score: 2 · on Selling Your Wireless Traffic to Passers-By

I am not a lawyer, so don't rely on this as legal advice.

Generally, my experience with DSL providers has been that they do not prohibit this kind of sharing. Indeed Covad's sales staff touts this kind of unrestrictedness as selling point. (I called Covad's sales line to confirm this a while ago.)

This is not so surprising when you consider that the places where wireless service is expected to be most useful are "hot spots" where people gather and sit down, such as resturaunts, coffee shops, retailers, and various waiting areas, typically places that are likely not to order broadband otherwise.

It is difficult to prove a negative. So, maybe those who believe their acceptable use policy prohibits this should provide relevant excerpts. It would be interesting to see if those AUP's also, with the same stretch of interpretation, prohibit attaching a wireless access point, using Network Address Translation to connect more than one computer, or using the connection for work.

By the way, my impression is that DSL people seem to be more positively disposed toward this sort of thing than the cable modem providers.

Disclaimer and plug: I am involved in LANRoamer, a GPL'ed wireless roaming network that allows people to get paid for providing wireless service. The back end is also GPL-compatible open source.

GPL'ed LANRoamer has been doing this for a while by Adam+J.+Richter · 2002-03-08 01:07 · Score: 3, Informative · on Linuxcare Founders Go Wireless

LANRoamer is a GPL'ed system that has been doing this for a while. We gave presentations on it at Bay Area Wireless User Group and Sbay.org back in June, I believe, before even the NoCat project started.

If you're into "bazaar" style software development, one thing you should note is that LANRoamer does network booting and upgrade reboots. So, if you contribute a useful feature to LANRoamer, it can be widely deployed quickly (based on our stability labels and the stability level each gateway owner has selected). Also, in addition to free accounts and revenue sharing to our access point providers, we also offer free courtesy accounts for people who run open access points (not just during a free beta), partly in an effort to thank the developers and "evangelists", but also to get them involved.

Anyhow, here is the software, including the latest LANRoamer network boot floppy or CD-ROM.

The network boot floppy currently requires that the first ethernet card be compatible with 3COM 3c59x, 8139too, Ether Express Pro 100, NE2000 PCI cards, Via Rhine, Tulip cards and PC-Net PCMCIA ethernet (the 802.11 card or the ethernet connection to your access point can be just about any card that Linux supports). Unlike NoKat (the last time I checked), LANRoamer can work behind firewalls, including NAT routers, even ones that distribute IP addresses that LANRoamer would otherwise use. Once your gateway is up, client machines can obtain addresses from your wireless gateway by DHCP and are taken to an SSL-based login page when they try to go anywhere on the web until they log in.