This is the problem to solve first. It doesnt help to increase complexity with sync when basicAs everybody here whe have problems with interfering APs at the towers even if they are 40 MHz far away.
They do not need to build their own card but need to cooperate with a manufacturer like Atheros in a@ste
How long must we wait before a company like MT or Ubiquity will build their (really ) own wireless card? Fibre connections are pentrating the market here and we will not build our own fibre network with the high risk to loose our money in cause of a cross-subsidized telecom company who is gotting crazy.
I need a solution in an planable, aceptable time line!!! for this people only looking for the access-prices. One the one side to fix the customers we already have and on the other side to get new ones ...
For about 1 and 1/2 year I discussed the AP Syncfeature here and at the Ubiquity forum. The company who did it was ...
MT should hear more for the whishes of their users or they should make a statement "We don't see a future market in the industry nations". Then I know where am I!
Do you have a spectrum analyzer? I can fix that problem right now. Call me and I can teach you how and why. If you just want an answer. Move your aps aparts at minimum 10 ft. If the antennas are right next to each other. If two aps at 20mhz right next to each other. They are really 40mhz each or more. Thats how frequencies work within 10ft. Want proof. Buy spectrum analyzer. Glad I could help.This is the problem to solve first. It doesnt help to increase complexity with sync when basicAs everybody here whe have problems with interfering APs at the towers even if they are 40 MHz far away.
wireless behavior is low quality. With good engineered Wireless Cards/Drivers we would not see this
much interference issues we see.
I've just the poor mans Analyser (wispy dbx). I understand that distance matters. But I see equipment which canDo you have a spectrum analyzer? I can fix that problem right now. Call me and I can teach you how and why. If you just want an answer. Move your aps aparts at minimum 10 ft. If the antennas are right next to each other. If two aps at 20mhz right next to each other. They are really 40mhz each or more. Thats how frequencies work within 10ft. Want proof. Buy spectrum analyzer. Glad I could help.This is the problem to solve first. It doesnt help to increase complexity with sync when basicAs everybody here whe have problems with interfering APs at the towers even if they are 40 MHz far away.
wireless behavior is low quality. With good engineered Wireless Cards/Drivers we would not see this
much interference issues we see.
The goal is to use at much spectrum as possible without wasting it. That is a big problem with wireless cards. If you have 3 sectors. They each have a channel. If they are not speaking, they are wasting. Sync would give us full use of the whole spectrum on one channel.
This is no practical solution. You get a lot of latency. You need 6 slots. One for each AP and oneI would like to have 3 APs on a tower that can share the same frequency without interference. Like time slotting.
Then you get problems with cpe's which are on the border of 2 sectors. They receive@ste: You don't have to have a slot per ap. All APs are sending at the same time.
May be it's possible and necessary to live with "plastic stuff" for CPEs. But your service will suffer
When we talking about "plastic stuff": As ste said: The business is getting professional. In most countries time for handycraft work is over (yes we have an 18GHz spectrum analyzer but I don't and I can't have a handtuned wireless central tower). At the same time the bandwidth demand is raising combined with the will to pay less as possible. Returning to the issue "plastic stuff": We need a soluting where the CPE is very cheap and customer friendly (self setup). And if we could work with ap sync and a very cheap basestation we have a limited time to stay at the market. If the plastic stuff has the technology to prevent interferences why should spend time and money (for solid stuff) to reduce but not to solve the problem:
I wan't AP sync too.
Then you get problems with cpe's which are on the border of 2 sectors. They receive@ste: You don't have to have a slot per ap. All APs are sending at the same time.
1. But both cpes will see both sectors. With sync they will not disturb the ap whileThen you get problems with cpe's which are on the border of 2 sectors. They receive@ste: You don't have to have a slot per ap. All APs are sending at the same time.
signal of 2 APs at nearly the same signal level.
The main problem is at the ap side. There are ways to avoid 2 customer next to each other that are on different aps. like
1. make sure the antennas cant see each other.
2. use rts/cts so they take turns(which doesnt effect whole ap
3. polling etc...
The aps are closer so they just wont work. So the aps need to have slots. Right. I am open for discussion.
You get some benefit syncing APs on nearby towers.Why use GPS for AP sync? Isn't enough to have some sort of IP connection between AP-s to do this?
The one reason i want it is so I can use more of my spectrum without wasting it.Why use GPS for AP sync? Isn't enough to have some sort of IP connection between AP-s to do this?
The goal is: Maximize sector thruput and minimize problems arising from interference.I see that almost every poster on this thread thinks of something else when they talk about gps sync I still don't understand what you want to be implemented.
"only 1 wireless card talks at once", "All APs are sending at the same time. ", " share the same frequency without interference", "which works with 4 Sectors and 2 Frequencies", "have some sort of IP connection between AP-s to do this", "requires Layer-2 connectivity between the participating APs"
Hello Normis,I see that almost every poster on this thread thinks of something else when they talk about gps sync I still don't understand what you want to be implemented.
"only 1 wireless card talks at once", "All APs are sending at the same time. ", " share the same frequency without interference", "which works with 4 Sectors and 2 Frequencies", "have some sort of IP connection between AP-s to do this", "requires Layer-2 connectivity between the participating APs"
I think Mikrotik should make the NV2 protocol to support a GPS wireless sync. If Mikrotik setup the GPS sync. They will test it in the test lab. Using to aps right next to each other. If it works there with a -19 signal seeing each other. If they can pull lots of bandwidth from each ap and see the sync is working. I think that would be a good test right before production users use it. I will support testing this feature in production for Mikrotik. This will stop self interference which is the #1 problem with WISP. Most of the WISP dont even know they have this issue. I have have proven this over and over to other wisps about this problem. This fixes the invisable problem(To most users). I dont want to get off this subject too much. Anyways. I support the Airmax Ubquiti GPS sync design.The goal is: Maximize sector thruput and minimize problems arising from interference.I see that almost every poster on this thread thinks of something else when they talk about gps sync I still don't understand what you want to be implemented.
"only 1 wireless card talks at once", "All APs are sending at the same time. ", " share the same frequency without interference", "which works with 4 Sectors and 2 Frequencies", "have some sort of IP connection between AP-s to do this", "requires Layer-2 connectivity between the participating APs"
As wisp with multiple towers with overlapping segments some sort of
global (gps) sync may help.
Nevertheless the implementation is complicated and may lead to some additional
problems. As your implementation depends on Atheros you are bound to their
technical restrictions.
May be implementing this features is to far away from the standard 802.11 path
which keeps things cheap. Lets see if UBNT implements a *proven* sync feature.
I see moto-wimax users did not profit from sync as much as the feature promised
they switched to ABCD sector scheme as ABAB did not workout with sync.
As vacation gives me some time to read a background wimax book I can extend
the wishlist far beyond sync features. So e.g. PUSC is a great feature addressing the
same problems. But this even more leaves the path of 802.11.
I would appreciate MT to talk with sequans or beecem to open up the door for
a bunch of new features.
how do you think Nv2 works? It's the same thing, only without GPS.i dont understand why it even matters what time source you use, as long as everyone is on the same one. if you get 30 people in a room shouting at once its really noisy, and then tell each one to take turns, one right after the other, then its nice and peaceful - why can't mikrotik just listen to the other radios and adjust themselves without gps? the clients already do this, why cant aps?
Normis, does TMDA allow several aps next to each other to share the same frequency without interference? I know TMDA does this for stations but does it help for access point to access point using the same frequency? If so, Each ap is added to the time slot?how do you think Nv2 works? It's the same thing, only without GPS.i dont understand why it even matters what time source you use, as long as everyone is on the same one. if you get 30 people in a room shouting at once its really noisy, and then tell each one to take turns, one right after the other, then its nice and peaceful - why can't mikrotik just listen to the other radios and adjust themselves without gps? the clients already do this, why cant aps?
http://en.wikipedia.org/wiki/Time_divis ... ple_access
I see that almost every poster on this thread thinks of something else when they talk about gps sync I still don't understand what you want to be implemented.
"only 1 wireless card talks at once", "All APs are sending at the same time. ", " share the same frequency without interference", "which works with 4 Sectors and 2 Frequencies", "have some sort of IP connection between AP-s to do this", "requires Layer-2 connectivity between the participating APs"
No it doesn't at all.Normis, does TMDA allow several aps next to each other to share the same frequency without interference? I know TMDA does this for stations but does it help for access point to access point using the same frequency? If so, Each ap is added to the time slot?how do you think Nv2 works? It's the same thing, only without GPS.i dont understand why it even matters what time source you use, as long as everyone is on the same one. if you get 30 people in a room shouting at once its really noisy, and then tell each one to take turns, one right after the other, then its nice and peaceful - why can't mikrotik just listen to the other radios and adjust themselves without gps? the clients already do this, why cant aps?
http://en.wikipedia.org/wiki/Time_divis ... ple_access
We would love to, but I don't understand what you want exactly. There seem to be many things called "wireless sync". I simply wanted some clarification to understand which things do you find the most important. Is it really only in the name of it ?I am not really sure that end users care how you do it as long as it works, after all you guys are the experts developing the software
You really need to have the ability to sync remote towers also. If not you are only bandaiding the situation, If you had no other wisps in the area raising the noise floor then you may be able to get a way without tower to tower sync. But where I am at to make the best use of the spectrum we have I need to be able to use the cleanest channel I can find on as many towers as possible.Thats exactly right. I need ap/ap real bad so I dont want to give mikrotik to much to do right now. I say hold off on gps timing and have master and slave timing for the timing source of that one tower.
Yes I agree. I was just saying that mikrotik didnt have a build all of it at once. One step at a time. They havent built sync before so I thought it would be easier for them.You really need to have the ability to sync remote towers also. If not you are only bandaiding the situation, If you had no other wisps in the area raising the noise floor then you may be able to get a way without tower to tower sync. But where I am at to make the best use of the spectrum we have I need to be able to use the cleanest channel I can find on as many towers as possible.Thats exactly right. I need ap/ap real bad so I dont want to give mikrotik to much to do right now. I say hold off on gps timing and have master and slave timing for the timing source of that one tower.
Thanks for your opinion corky. Thanks for your support.Sync between APs on a tower is more important than sync between towers.
I would disagree, Most wisps even if they are on different channel. They still self interfere on same tower. I know this because I got a spectrum analyzer. The customers connecting to Tower A will have a great signal then the signal coming from the remote tower. Thus you will have a greater margin. Your customers will work good. However I do agree we need gps sink for remote tower syncing. And yes we should have that feature.
I'm thinking though that doing it with GPS may not be any harder. In fact it may be easier.
With Moto, you have to cable between the APs to give them all a sync. MT would have to engineer that somehow. If they are going to have to engineer something anyway, it may be just as easy to go ahead and use GPS as the sync source.
Units like this are available off the shelf and communicate over USB.
http://www.amazon.com/Garmin-18x-USB-Na ... 785&sr=8-1
It's affordable, weather proof, and the software interface is already worked out. See here:
http://www8.garmin.com/manuals/425_Tech ... cation.pdf
MT could just automatically align to even second boundaries and presto -- all the APs are in sync w/o need of any new hardware at all. All APs on this and all towers would be in sync.
This limits the problem for MT to a pure SW solution. Of course we would have to change our APs to use routerboards that have USB, but that is a small price to pay.
That statement is sales driven and I think Mikrotik need to reverse the order (1) get resources first (2) build working products (3) sales -product purchase (4) supportYou know how that works. If you buy our products, we get more resources to make such things. So - keep buying our products. Did you order the SXT already ?
I would assume that there is more than just software programming involved for this to work, other items in this chain to be considered are radio card and antenna, also if the radio card is made by another company and if unannounced component changes are done this could alter performance, in short Mikrotik need to make the complete package then and only then will they have control, otherwise we could or will have with different builds of these components when purchased will result in software "hotfixes"??I can't see why not. This is only a software change. As long as the board supports a gps.
Any idea if this is something that may slip into v5 or not?GPS sync is in our to-do list.
This is what I needed to hear. As long as its implemented in a timely fashion, Mikrotik will continue to see business from me.GPS sync is in our to-do list.
I think this is the best explanation in the thread of the desired functionality.You link the sectors to a common time source, then you have them broadcast for 10ms then listen for 2ms *at the same time*. So when North is broadcasting, so is South. Then they both fall silent at the same time and listen. Notice that when they are listening for their clients, the other AP is silent, so there is no interference from the other AP even though it is on the same channel. For this to work, you need decent quality sectors that can't "see" each other's clients. If you have sectors with 27db back end rejection. Consider a client on the South sector with a -65 signal. The North sector will see that customer with a -92 signal - so it does not interfere with the North sector even though it is on the same channel. This is probably why UB created their own antenna line.
This is an excellent first step that requires no new hardware.What about your boards that support multiple cards(RB600, RB800, RB433, etc.), can they be set up so that each card sends and receives at the same time.
Most WISPs have limited understanding of the physics involved in wireless communication. For most customers, any kind of sync will have very minimal benefits but it will help you sell more units because it is the latest hype. Far more can be achieved with proper network design than with sync.There seem to be many things called "wireless sync". I simply wanted some clarification to understand which things do you find the most important. Is it really only in the name of it ?
Are you sure that is what you really want?
With the next upgrade to our network we are requiring both AP sync, and tower sync. I know there has been alot of confusion on the topic, but generally speaking, I want the all APs throughout the network using a specific spectrum (900 MHz, 2.4 GHz, 5.8 GHz) to all transmit simutaneously.
Most WISPs have limited understanding of the physics involved in wireless communication. For most customers, any kind of sync will have very minimal benefits but it will help you sell more units because it is the latest hype. Far more can be achieved with proper network design than with sync.There seem to be many things called "wireless sync". I simply wanted some clarification to understand which things do you find the most important. Is it really only in the name of it ?
Are you sure that is what you really want?
With the next upgrade to our network we are requiring both AP sync, and tower sync. I know there has been alot of confusion on the topic, but generally speaking, I want the all APs throughout the network using a specific spectrum (900 MHz, 2.4 GHz, 5.8 GHz) to all transmit simutaneously.
Do you realize that if a client radio can hear 2 or 3 APs, there will be so much noise that data rates will drop virtually to zero?
Proper sync will require very careful physical planning where no device ever hears more than one other device.
Replacing the cards would be my last option. If mikrotik did the card. It would be one frequency at a time. I got 3.65ghz 2.4ghz 5.8ghz 900mhz etc.. It would take too long. I like the idea that we can use any frequency and any card.I dont believe a successful GPS sync method can easily be done in software alone. We are talking microseconds, not milliseconds when it comes to the TDD timing of TDMA. In theory there would need to be a very tight timing interface directly to the WiFi card involved - and thats assuming the WiFi card is even capable of having its timing provided externally in the first place.
It would probably be easy to sync WiFi cards connected to the same motherboard but this would only achieve sync at the same tower at best. What about the the other tower on the hill that faces this tower 10km away for example?
I am guessing for MT to achieve a proper GPS sync method, they would possibly need to release a routerboard or WiFi card with a proprietary GPS input socket. Or ideally accept the pulse from an industry standard 1PPS GPS source.
I am wondering if maybe there is such a WiFi device currently on the market somewhere? Eg a standard minipci device that the O/S and related hardware communicates with just like a normal WiFi card, but the card itself has a separate connector that accepts a GPS sync pulse.
This dream WiFi card would be compatible with ALL systems without the need for operating system vendor integration.
Hmmm....
The standard GPS sync method we are trying to achieve here with MT is very much more complicated than that.Here is my though. We have ap A 5 miles away from ap B. Ap A would probe all aps and ap B would respond. Giving us the almost exact timing. I think this is almost the best approach. If we can time to the gps satillites, why cant we time to our own access points. That would be faster. Once the timing is set, it will propergate thoughout the network.
Quoting myself here after an interesting revelation just spotted on 'another vendors' wifi TDMA forum.The downside of sync'd TDD that many people are not aware of is that there also needs to be uplink and downlink ratios defined across all radios playing ball in the same sync'd network for it to be effective. EG you have to define if the radio network will be 50/50 up/down or maybe 25/75 up/down that is more generally the case. This means your AP with a total capacity of 20meg now becomes limited to 10meg down and 10meg up assuming a TDD uplink/dowlink ratio of 50%
Almost my whole network is using NV2 and it works great. I am also using 802.11N and it works very well. Great results. With the new features that Mikrotik has to offer. I am providing very releighable internet to rural market. I am setting up a new system that is full duplex and I can offer 100mbps to customer 6 miles away and 60mbps full duplex at 10 miles. Can I help you with some mikrotik stuff?Don't get too excited Dallas. They have not said they are going to do this. Last I checked, N is not even working well enough for a WISP to use. With great sadness we have quit deploying MT as CPEs and APs, we only use them for routing boxes now. We are even starting to remove them from the field and replace them with other gear. It's really painful. We loved the power and interface, but our customers demand more speed and more reliability.
Reading the forum of this competitor I do not see AirSync working.Many clients wondering when this new option is available in mk because they are starting to migrate to competitor AirSync...
Any position???
How does plastic rust? he he.I see rusting equipment and a lot of problems.