My thoughts exactly. If the VL had a mechanism to "tune out" noise and a few other tools (dual pol - dual band) that would enable the user avoid noise then it is possible there simply would not be a better PtMP LE product available today. Without those critical elements the VL is just not able to perform consistently in RF hostile environments.
The Alvarion VL is great for bursty, best effort requirements where 90% of the user applications can wait for that clear air within the noise floor, but not for committed rate business class service. Best, Brad -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Marlon K. Schafer (509) 982-2181 Sent: Tuesday, December 26, 2006 11:46 AM To: WISPA General List Subject: Re: [WISPA] Alvarion Comnet Radios have arrived Got it. Thanks. I guess my "beef" comes from being a wifi based wisp. I find it too difficult to reject interference with a csma based product. Anything with a "wait for clear air, then transmit" MAC is GREAT for collocation. But sucks when there are products around that don't follow that mechanism. That's (my personal belief) why Canopy went with it's GPS sync. It doesn't care who's already out there, when it's time to transmit it does. Trango does that to, just without sync'ing the AP's. My REAL world experience so far is that csmak (or csma/ca, or whatever collision avoidance scheme you want to use) is GREAT where there aren't many other systems within ear shot of the radios. However, when there are other devices in the area, especially those that don't have a collision avoidance mechanism, the csma radio will pay a heavy price in performance. Having used both csma and polling products, I'm not putting in any wifi type products at 5 gig. All of our next gen products will be polling as long as we can keep things that way. These days, I'm learning to sacrifice raw performance for reliability and uptime. There's a balance, sure, but getting that last 10 to 20% out of a product is less important to me than having a product that can survive some of the games that my less scrupulous competitors play. However, with EITHER technology choice, it's critical to design a network that can, and does, physically (antenna choice and ap locations) isolates your system as well as you possibly can. That seems to be the type of trick that just can't be taught. Your network designer either gets it or he doesn't. Heck, I've even done consulting gigs where I looked a guy right in the eye and gave them several choices for site locations. Only to have them pick something completely different, and sometimes unworkable. 80 to 90% of people's problems with wireless are self inflicted. Either outright or in a lack of forethought manner. Here's an idea for you Patrick. Make this product work both ways. Give it the option to be either csma or some fancy new version of token ring. Then we could optimize performance for any environment that we find ourselves in. Oh yeah, I remember the big hubbub about GPS in the BreezeACCESS II line. Why was it important for collocation then but not now? Hope you guys all had a great Christmas! Marlon (509) 982-2181 Equipment sales (408) 907-6910 (Vonage) Consulting services 42846865 (icq) And I run my own wisp! [EMAIL PROTECTED] www.odessaoffice.com/wireless www.odessaoffice.com/marlon/cam ----- Original Message ----- From: "Patrick Leary" <[EMAIL PROTECTED]> To: "WISPA General List" <[email protected]> Sent: Tuesday, December 26, 2006 9:26 AM Subject: RE: [WISPA] Alvarion Comnet Radios have arrived I'd never call you a neophyte, Marlon. A jolly elf maybe, neophyte never... CSMA/CA. But the MAC has been substantially altered, especially with 4.0 and the WLP (wireless link prioritization) feature where all stations can be made to wait while those stations with spooled up voice can release their packets regardless of where they are in the cell. Also, in VL an operator can adjust numerous values of the CSMA/CA, such as contention window duration, contention levels, etc. It is more sophisticated than your basic polling and more efficient. Patrick Leary AVP WISP Markets Alvarion, Inc. o: 650.314.2628 c: 760.580.0080 Vonage: 650.641.1243 [EMAIL PROTECTED] -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Marlon K. Schafer (509) 982-2181 Sent: Tuesday, December 26, 2006 9:13 AM To: WISPA General List Subject: Re: [WISPA] Alvarion Comnet Radios have arrived Got that part. I still didn't see in there anywhere, in plain English that a neophyte like me can understand, is this a polling or csmak product? Marlon (509) 982-2181 Equipment sales (408) 907-6910 (Vonage) Consulting services 42846865 (icq) And I run my own wisp! [EMAIL PROTECTED] www.odessaoffice.com/wireless www.odessaoffice.com/marlon/cam ----- Original Message ----- From: "Patrick Leary" <[EMAIL PROTECTED]> To: "WISPA General List" <[email protected]> Sent: Friday, December 22, 2006 1:54 PM Subject: RE: [WISPA] Alvarion Comnet Radios have arrived Marlon, I'll answer this with a re-post of a September post that explains, in part, why VL is not just regular CSMA: <<trim>> -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ ************************************************************************ ************ This footnote confirms that this email message has been scanned by PineApp Mail-SeCure for the presence of malicious code, vandals & computer viruses(190). ************************************************************************ ************ ************************************************************************ ************ This footnote confirms that this email message has been scanned by PineApp Mail-SeCure for the presence of malicious code, vandals & computer viruses(42). ************************************************************************ ************ **************************************************************************** ******** This footnote confirms that this email message has been scanned by PineApp Mail-SeCure for the presence of malicious code, vandals & computer viruses. **************************************************************************** ******** -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
