I have suggested a FDD-style system like this on the MT forums before. My thoughts were to have a full-protocol scheme like NStreme dual but tailored for PTMP. HOWEVER, utilizing some bridge / mangle / filter tricks I have done FDD schemes without NStreme-dual, making re-use and hidden node a very small issue and performance much better on FDX traffic. CIR/MIR is easier to manage - and oversubscription becomes a smaller issue.
If I could find some decent CPE dual-polarity antennas, I would do this in a heartbeat. I have a tower to re-do, and I may go this route if it works well in the lab. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Hammett Sent: Monday, June 11, 2007 10:38 AM To: WISPA General List Subject: Re: [WISPA] MT Babble On a volume of 1, I can get a 5 GHz CPE for $185. IIRC, 100 unit quantities were $140. I can configure 2 CPE for a PtP. I can have an AP that has 4 radios for about $800, plus cables and antenna. I can configure 5, 10, 20, or 40 MHz per radio, two radios are required for full duplex operation. The 70+ megabits is with 40 MHz. With the full duplex operation I can configure the same frequency for all transmitting on a given tower, allowing for major frequency reuse. I agree that this route isn't as spectrally efficient as Orthogon or... I forget the new guys... Exalt? The XR5 radio has 23 dbm at 54 meg and 28 dbm at 6 meg. It also ranges from -74 to -94 for receive sensitivity. That radio has been certified with a 31.4 db antenna. I haven't tried, but I'd imagine putting a similar channel size would result in a similar number of collocated APs, though I don't know. MT is different than generic 802.11 in that it has the N-Streme protocol, solving many (if not all) problems with using 802.11 in WISP applications as well as allowing for a much higher throughput. Star-OS has a similar feature. Everything else 802.11 is plain vanilla. I have nothing wrong with every radio being MT. You can use 900, 2.4, and 5 GHz (not 5.4) with any antenna (as long as the gain is under the certified gain for that radio), allowing for any combination you could want. The exceptions to this that I know of are Orthogon's spatial diversity and any sort of MIMO, beam steering, etc. You can put as many cards as you want on a given PC based Mikrotik system. I am unsure of the innerworkings of the QoS. I do know that I can prioritize what goes into and out of each interface independent of any other interface. I would imagine that if it was certified with 32 radios, you could use 1 radio and be fine, though I am not fully aware of those specifics. I would assume that you could have both setups certified, and could then add the second radio to the first, making it the second certified system. Star-OS is the only system that I know of that has anywhere near the feature set of Mikrotik. What features is it missing? They could already be incorporated or slated for 3.0, which is in beta as we speak. ----- Mike Hammett Intelligent Computing Solutions http://www.ics-il.com ----- Original Message ----- From: "Matt Liotta" <[EMAIL PROTECTED]> To: "WISPA General List" <wireless@wispa.org> Sent: Monday, June 11, 2007 9:04 AM Subject: Re: [WISPA] MT Babble > Mike Hammett wrote: >> Speed, features, reduced points of failure, price. >> >> If I can setup two complete and separate MT systems for less than the >> other guys can... Heck, could probably even setup a wireless ring using >> different bands for each link for less than the other guys. Even the >> greatest gear will lose out to basic redundancy. >> > Can you give me some idea what the cost is? Last time I looked the cost of > MT was similar to other vendors. >> Speed. I can setup a full duplex link that can do in excess of 70 >> megabits with a single set of gear. I can increase that in 70 megabit >> increments as tower space (for additional antenna) and available spectrum >> allow, all having a single Ethernet cable handoff. >> > What kind of channel space, receive sensitivity, and power output do you > have in such a configuration? >> With proper RF engineering, I can have sectors deployed that can provide >> 10 megs plus to each user. When your system can do 70 megs plus, you can >> fit a lot more customers with higher speeds. He who can scale wins. The >> more bigger pipes you sell, the cheaper your bandwidth becomes. When >> your bandwidth is cheaper, not only can you pass this along to your >> customer, but you can also profit more. I can have multiple customers on >> a sector that each can consume more bandwidth than a Canopy AP could only >> dream of supplying. >> > Canopy certainly has the least amount of available bandwidth among the > available systems. However, when it comes to scale, I haven't seen a > single vendor who could colocate more APs at one location than Canopy. In > this case though, I would think comparing MT to another 802.11-based radio > would make more sense. Can't those radios do 10Mbps plus to each user? >> In an AP application all electronics are in one system. I don't need to >> have a bunch of patch cords and a switch and a router and a {etc} sitting >> on a tower. All coax runs into one box that hosts the AP. All sector to >> sector to backhaul to backhaul communications are internal, allowing for >> greater flexibility in traffic control and uptime (reduced failures). >> > I agree it is nice not to have a ton of components. However, the above > would seem to require every radio at the site to be MT or you would still > need to have separate components. >> When I implement a QoS feature or a firewall or a {etc} I can do so >> directly on the inbound interface, before it has gone completely through >> the AP, through a switch, and into a router. The AP is the router. >> > Does the QoS feature actually prioritize the radio? Obviously, people who > use a separate route/switch can apply QoS, but it doesn't affect the > radio. The radios we use allow prioritization on the radio itself, which > is very useful. >> When I need to add another wireless interface to a system (AP, backhaul, >> CPE, etc.), I can just add a mPCI, antenna, and cables. This is an even >> cheaper route than a new MT system, which is cheaper than just about >> anything else you could do. Again, all of the above advantages also >> apply here. >> > That certainly is nice, but is that going to work in the future when the > system is certified? I didn't think you could have a certified system > where it is possible to add additional radio cards at a later date. >> MT (and I believe Star-OS) can do everything. It is far easier\cheaper >> to get an MT system certified (which would only require a firmware that >> was restricted to US band options) than it is to have Motorola or Trango >> or Alvarion completely overhaul their entire lines to have the same >> abilities. >> > I don't agree MT can do everything since it is missing several key > features we require. However, I do agree that the vendors you mention > above don't have the anywhere near the features of MT, nor do I think they > want to. What about the other 802.11-based radios though? > > -Matt > -- > WISPA Wireless List: wireless@wispa.org > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ > -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.472 / Virus Database: 269.8.9/832 - Release Date: 6/4/2007 6:43 PM -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
