2.4 GHz wireless back haul.
I am looking for a wireless radio bridge to replace an old 2.4 Speedcom link. The antennas and feedlines are ok so I just need two radios. The path is 10 miles and is near line of sight, speed is 10 meg. Anyone have a suggestion? What brand is a good one? Dwight Dwight L. Hazen Indiana University, UITS Bloomington, In. 47408-7378 812-855-5367 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] Spectrum Analyzer for interference detection
Title: Spectrum Analyzer for interference detection Ron, I would look for a micro wave oven or a 2.4 gig cordless phone near your classroom. Dwight Dwight L. Hazen Indiana University, UITS Bloomington, In. 47408-7378 812-855-5367 -Original Message- From: Robinson, Ronald [mailto:[EMAIL PROTECTED] Sent: Tuesday, April 04, 2006 3:58 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] Spectrum Analyzer for interference detection Greetings listers, We have a suspected interference problem in a particular classroom that causes all the wireless connections to drop at the same time. There are two APs in the classroom, and only one other AP in the building (that can be seen with NetStumbler), all are on non-overlapping channels. It only appears to affect one particular class, but that class has 23 students all trying to use the wireless simultaneously. I have replaced the single Cisco 350 access point with two 1200 series and have the same reported symptom. I am beginning to suspect a wireless card in one of these students laptops as a possible source of the problem, hence my request... Any advice on the best tools or procedures for determining if there is actually an interference problem in an 802.11B/G environment? Would a Spectrum Analyzer be of any use in tracking this down? Anyone have experience with any software based Spectrum Analyzers? Thanks -- Ron Robinson, Network Architect, Bradley University 1501 West Bradley Ave. | E-Mail: [EMAIL PROTECTED] Morgan Hall Room 205F | Phone: (309) 677-3350 Peoria, Illinois 61625 | FAX: (309) 677-3460 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] AirWave inquiry
Jim, We have 1000 wireless units on one AMP server, the server is dual processor with 4 gigs of memory. We have no problems with frequent crashing. The server is now running too slowly so we are adding a second server and plan to divide the wireless units between them by subnets. I have changed the polling to 15 min. after I get the new server I will go back to 5 or 10 min polling on both servers. Dwight Dwight L. Hazen Indiana University, UITS Bloomington, In. 47408-7378 812-855-5367 Ham Radio [EMAIL PROTECTED] http://wb9tlh.ampr.us -Original Message- From: Jim Gogan [mailto:[EMAIL PROTECTED] Sent: Saturday, December 10, 2005 12:50 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] AirWave inquiry I've seen a lot of favorable comments and reviews here and elsewhere about AirWave (network management app). We've been using it ourselves for a while and really value the info we get from it . when it's working properly. It's gotten to the point where we have to reboot it several times a day; the load average creeps up to 12 or higher, and it becomes unusable. Even after a fresh reboot, usage is only barely tolerable. We can't depend upon it in a critical situation. We investigated putting it on new hardware (we're upgrading a number of our net mgt server platforms to Sun X4200s running Linux), but were informed by the AirWave folks that they don't have 64-bit support. Not only that, but in further discussions, we learned that most of the components for AirWave are written in Perl, which isn't exactly the most efficient programming platform.Disillusionment sinks in it's like learning from the Easter Bunny that there is no Santa Claus! So, my questions to those of you that do wax enthusiastically to this day about AirWave: 1) How many WAPs are you currently managing with a single Airwave appliance? 2) What is the (average) polling interval used? 3) Do you have multiple Airwave servers, and if so, how many WAPs managed on each one? How do you plan to scale--additional separate servers, or a beefier single server? 4) What are your server specs? (Vendor, OS, number of CPUs and their speed, amount of RAM, number of active NICs, etc.) 5) How is performance on your server? Do you notice performance degradation over time? About how much memory is used under average load? How busy are the CPUs under average load? How much network traffic is generated from polling? Also, optionally: 6) How do you manage security concerns? (i.e. most Airwave processes running as root, installed in /root, root ssh remote logins enabled by default on default port, most components are written in Perl which can easily be modified if the machine is compromised, compilers are installed locally, etc.etc.etc.) Inquiring minds want to know (and want to get the statistics we need to manage the network). Thanks in advance! -- Jim Gogan ([EMAIL PROTECTED]) Director, Networking ITS University of North Carolina at Chapel Hill ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: Re: [WIRELESS-LAN] Question about fluctuating transmit rates
I have always enabled the default storm threshold on all our units. Early testing indicated better performance when overlapping coverage from multiple access units. Dwight Dwight L. Hazen, Indiana University, UITS Bloomington, In. 47408-7378 812-855-5367 IP phone 317-278-4014 [EMAIL PROTECTED] http://php.ucs.indiana.edu/~hazen/ Ham Radio [EMAIL PROTECTED] http://wb9tlh.ampr.us -Original Message- From: Matt Ashfield (UNB) [mailto:[EMAIL PROTECTED]] Sent: Wednesday, October 02, 2002 9:53 AM To: [EMAIL PROTECTED] Subject: Re: [WIRELESS-LAN] Question about fluctuating transmit rates Hi, We have experienced the transfer rate fluctuation using Lucent and IBM cards in the AP-2 (I too am confused what vendor name to use!). One thing I have just done is enabled the storm threshold (using their default value) and this seems to have solved the problem, mind you I'm still waiting for all the test results. But when the transfer rate was fluctuating down to 1mbs, we saw non-unicast packets also shooting up, and a constant ping that we had running started dropping packets. Enabling the storm threshold in the AP-2 seemed to prevent this from happening. Has anyone else had success using this storm threshold? Or should I have had that turned on from the beginning (quite likely). Cheers Matt Ashfield [EMAIL PROTECTED] - Original Message - From: Philippe Hanset [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 11:39 AM Subject: Re: [WIRELESS-LAN] Question about fluctuating transmit rates Matt, We have experienced this with client joining AP-2000 (I assume that AP-2 is the same as AP-2000...I always got lost with the AVAYA/AGERE/ORINOCO/PROXIM naming mess) with D-Link and Linksys cards. Even though their signal strength shows in the 30 dB SNR, they transfer rate is in the 1 Mbps range... A trouble ticket has been submitted to PROXIM (or will be!) We also noticed that AP-2000s with 2 cards in it self-reboot on a random basis. Have you tried the new code release? Does this occur with Lucent cards as well? Philippe Hanset University of Tennessee On Tue, 1 Oct 2002, Matt Ashfield (UNB) wrote: HI All, I'm not sure if this list is still active, but thought I'd throw out a question here. I have some Lucent AP-2's installed in a building and users are complaining things are either very slow, or they sometimes have problem logging on. I took a laptop up with a wireless client and did some testing. It seems that the transfer rate between laptop and Access Point is pretty much always fluctuating from 1 to 2, to 5 to 11 Mbits/sec. I don't seem to have a lot of noise based on what the client software tells me. Has anyone seen this? My guesses are at the following: - A flaky card in the Access Point itself. - The positioning of the Access Point. The access point is mounted on the side of the wall, with the lights facing downward towards the floor and therefore the cards facing upwards. I'm wondering if this may case some of the problem. - We do have 2 cards in the Access Points. The channels are separated as best as possible, but it's possible some leakage from upper floors may be causing interference. Should I play with the Distance Between AP's setting if I have two cards in the one AP? Any advice/comments you could offer would be much appreciated. Cheers Matt Ashfield [EMAIL PROTECTED] ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/memdir/cg/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/memdir/cg/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/memdir/cg/.
