When will Mikrotik build a feature to sync aps?
Like Ubiquiti you mean?
I would like to have 3 APs on a tower that can share the same frequency without interference. Like time slotting.
This would be really neat so I can use 3.65ghz sectors on 20mhz channels instead of 5mhz channels. I use 5mhz so I dont interfere with the other sector 20 ft away. We can only use 25mhz total so this feature would be a blessing.
Explain me in few sentences how it might work?
AP would need a GPS to get correct time for synchronization, and a protocol beetween each other to talk to and arrange time slots when they have to be silent.
How would you resolve issue with time drift ?
Its hard to imageine - set exact time on diffrent boards and keep it sychronized.
Where ist the problem? GPS chips are very cheap. You can ignore the drifting problem if you put an gps receiver at every AP and sync the clock in a short period.
This is the cheap way of two available ways to keep the wireless business a little bit longer alive. Without AP Sync your not able to increase the summary bandwidth on wireless POP’s. As everybody here whe have problems with interfering APs at the towers even if they are 40 MHz far away.
I don’t know what has happend with MT but from my point of view I see not much innovative things from them one year. O.k. again and again routerboard in many variants but this are not the things we can really use.
- MPLS was a nice try but the development seems to have stopped.
- No “ready-to-setup-for-customer” CPE like Ubiquity
- No SFP slots to use MT for a superior fibre-router.
- A good concept for a NMS (the dude) - I can’t see any constant development here. Instead of offer it for free it would
be better to sell it and push the development
NV is a light at the end of the tunnel but without AP sync most of the WISP will run into future bandwidth problem.
This is the problem to solve first. It doesnt help to increase complexity with sync when basic
wireless behavior is low quality. With good engineered Wireless Cards/Drivers we would not see this
much interference issues we see.
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!
They do not need to build their own card but need to cooperate with a manufacturer like Atheros in a
way that there will be a better product in terms of wireless behavior.
But I am not sure that MTs core competence is in that area. Reading documentation and following
discussions I do not feel that there is a deep understanding of wireless physics (I’m no expert in this
field either). It feels like they get cards from atheros, poke in some parameters and hope the best.
Wasnt the hardware-retry knob there for some time until it really gets used in 4.x. Looked like they
poked it into the wrong hardware register and did not even notice that this knob was not working.
We are looking/testing some wimax gear in the near future as it seems prices went down into a
reasonable range. This gear is double the price for the outdoor cpe and 8 times the price per sector
but it promises a much better behavior in terms of frequency efficiency and behavior under load/difficult
conditions (with GPS-sync).
Wisp market is getting more professional. Vendors which do not follow this way …
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.
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.
I’ve just the poor mans Analyser (wispy dbx). I understand that distance matters. But I see equipment which can
live on the same tower with just minimal frequency and physical spacing and I see equipment which has problems
even with big frequency and physical spacing. This has to do with quality of components (E.g. look at this plastic
UBNT stuff). You can throw 1000 features like sync on low quality equipment and your result will be far from optimum
What I want to say is: Increasing quality is prior to throw new features in the game. Doing this new features with
same low quality will not make a good product. Of course I want to have sync, too.
GPS sync will make it so only 1 wireless card talks at once. So you can have the equipment right next to each other without interference. It will solve your issue.
This is no practical solution. You get a lot of latency. You need 6 slots. One for each AP and one
for the group of clients of each AP.
I know synced equipment which works with 4 Sectors and 2 Frequencies. So you have one slot for AP and
one for clients. As same frequency is used back to back you minimize interference.
Cant we change the time slot size for this? As long as there is not interference we should only have little more latency than normal. But the benefit of using a full 20-40mhz channels is worth it.
Nv2-cell-radius - specifies distance to farthest client in Nv2 network in km. This setting affects the size of contention time slot that AP allocates for clients to initiate connection and also size of time slots used for estimating distance to client. If this setting is too small, clients that are farther away may have trouble connecting and/or disconnect with “ranging timeout” error. Although during normal operation the effect of this setting should be negligible, in order to maintain maximum performance, it is advised to not increase this setting if not necessary, so AP is not reserving time that is actually never used, but instead allocates it for actual data transfer.
@ste: You don’t have to have a slot per ap. All APs are sending at the same time.
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
signal of 2 APs at nearly the same signal level.
May be it’s possible and necessary to live with “plastic stuff” for CPEs. But your service will suffer
from “plastic stuff” at the AP-Side.
Some of this gear is made for low density usage. And there you can live with poor separation and
plastic. So it’s a good business decision to use cheap gear there. But some vendors claim 300+ Subs
per Tower. Try it and you get 300+ phone calls per day.
But of course MT shouldn’t be behind these plastic stuff guys in terms of wireless or they find
themselves selling only indoor equipment.
@ste: Shure. I will spend more money for a professional AP. I want to have more monitoring, more shielding and a really good lightning protection (my nightmare).
Then you get problems with cpe’s which are on the border of 2 sectors. They receive
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
- make sure the antennas cant see each other.
- use rts/cts so they take turns(which doesnt effect whole ap
- polling etc…
The aps are closer so they just wont work. So the aps need to have slots. Right. I am open for discussion.
- But both cpes will see both sectors. With sync they will not disturb the ap while
he is sending but both cpes will get signal from both sectors at the same time as they
are synced.
2./3. helps only for cpes registered with the same sector
Why use GPS for AP sync? Isn’t enough to have some sort of IP connection between AP-s to do this?