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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Jon Gerdes wrote: > Does anyone have any experience of long range wireless networking? Some 802.11b > Do you need line of sight between transmitters? Yes - absolutely - and minimal obstruction from things like trees. I'm assured rain can be an issue as well (my met man hat would make me expect snow (actually falling rather than sitting around looking pretty) to be a bigger problem!). > What is the true range? Depends on radio licencing issues, I have seen unmodified kit used to achieve a slightly dodgy 12 Km connection, but this mounted the unmodified unlicenced kit on satellite dishes, which the radio agency might not regard as "unmodified". I suspect the reality is for as long as you don't use excessive power or cause other people problems the radio agency will ignore you. > Who does the best gear? Intel WAPs - but the BT hotspot team told me Intel were dropping out due to Channel conflict - i.e. everyone was buying Intel, and not from their corporate customers. Orinoco cards are good, but the generic Prism II cards have the best support in Linux for doing "clever stuff", like making your own access point. Do check your Prism II vendor is up to date on Firmware releases from Intersil if you want to do "clever stuff" TM, whilst staying supported. I'm not up on proprietary antennas but the Intel products looked good again - watch out for incompatible (i,e, non standard) connectors for antennas. OFten you have to buy the antenna from the WAP or Card vendors. > Planning regs? My understanding is that you can place one antenna on residential homes without issues - we were looking at sky satellite disk blanks - so to the untrained eye it looks like a satellite TV antenna - the alert passerby will notice they don't all point south! > Interferance with existing 2.4GHz stuff? Not seen any - some report Microwave oven interference - fix your microwave quick if this happens. I'm told Blue tooth kit is a problem but I've never seen any so wouldn't know. > Realistic performance (11 or 22Mb - really!) ? 802.11b achieves about 5 Mbps point to point short range - realistic throughput over long links seems erratic. The 22Mb claim is a modified standard. 802.11g and 802.11a kit seems to be elusive. For planning purposes on short hops you can probably share out 5Mbps. You should easily beat dual channel ISDN over short distances, by an order of magnitude, laency can be quite high, and the WAP to WAP mesh use to have fair long drop outs on long hops - i.e. often 5 or 6 seconds. > Incidently I'm in Yeovil, which is not exactly in Devon & Cornwall I believe Somerset County Council use 802.11b extensively. > If anyone has any ideas or pointers, I'd be most gratefull. ISDN makes a good back-up - wireless is always less reliable. We did WAP to WAP bridging with Intel - seemed a cool solution. Their is a LEAF project for Wireless routers - seemed cool but you have to build with the right hardware to be sure of a good solution. The hostap mailing list has all the Linux Wireless gurus as regular readers - so that is where the action is at. I have done all the IP stuff for this kind of thing, but you really need a radio guru with experience of similar frequency, they can answer the planning issues. A local amateur TV group would be good to know as they do 1.2GHz I believe, so can even reuse some of their kit for some purposes. The radio people will explain why you need short leads from transmitter to antenna and similar issues. The netowrking stuff is just bog standard IP networking usually. -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQE+QXUgGFXfHI9FVgYRAsyuAKCZPjFDzodwxH3c9EvHW/35f5ZOMACgvIfc JJX9ly+VIDMut/Fam+cBw9g= =01Tm -----END PGP SIGNATURE----- -- The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe.