I have a possible opportunity to start a ‘Total’ wireless communication solution in surrounding rural areas, from where I live. My plan is to become more than a WISP, thus act as a kind of a telecommunication service provider. We want to discourage any fixed line solutions and substitute it with one wireless solution, carrying voice and data. The solution will be done with Mikrotik WiFi equipment and will be ±25% cheaper. I’m planning to roll out base stations with RB600’s, XR5’s and 3 x 120 degree sectors. The possible problem areas:
Because we’re carrying voice, uptime becomes critical. Specifically when you think about businesses, hospitals, police stations and so on.
I’m bit worried about scalability. Will WiFi be able to handle 100’s of simultaneous users, without any problems? How many users will one access point be able to handle? As said, QoS specifically for VOIP, will be CRITICAL.
Fail over. Is it possible to have secondary AP’s at the base station, enabling CPE’s to connect to the secondaries, when the primaries go down? If so, how does one setup the CPE’s to do this? If this is not possible, what other fail over solutions does one have?
With regards to scalability and Qos → WiFi vs Wimax? How does the price of Wimax Equipment differ from that of WiFi, percentage wise? Thus, how many % is Wimax Equipment more expensive?
Another question on supplying power to the RB’s. When one’s equipment is 50-100m up on a tower, what is the best and most stable way to supply power? I don’t like the idea of running DC power 50-100m directly up the tower to the RB’s? Is it better to house a AC power supply unit close to the RB’s? Thus, AC power up the tower into the power supply, then DC power out to the RB’s? And what if one does not have AC power, thus DC power via batteries? And what is acceptable specification on a power supply to use with heavy loaded RB600’s?
a hundred users per AP is really the maximum, i suggest less if you want a problem free installation.
you can set up some mesh-like setup where APs share the same SSID, and the client switches to another one, should the strongest signal disappear. The VoIP will not even notice, even if it’s during a call. Some people have done this.
you can set up some mesh-like setup where APs share the same SSID, and the client switches to another one, should the strongest signal disappear. The VoIP will not even notice, even if it’s during a call. Some people have done this.
Where/How can I do the mesh setup
power - what about PoE?
I have a site that runs on 2 x 102Ah, 24V DC power with 150W solar panels. The wire length is 15-20m. It powers 2 x RB433AH’s with 2 XR5’s in each. The RB’s will intermittently just shut down without starting up again! It cost me every time to drive 50km to the tower to take one of the battery terminals off and put it back on again. I first ran one set of 2 x 2mm wire, thus, positive and negative to the top, splitting it at the top to the two boards. With this setup I had shutdowns every 2 days. Then I run a set of wires up for each board, thus each board with its own positive and negative. With this setup I had shut downs every 2-3 weeks. Then I fitted 10000uF, 35V caps - problem solved.
So, my experience with power issues is not very pleasant.
if you want quick failover then you can do just like normis wrote - configure mesh kind network. Use the same SSID on all of the APs. Make sure that they are connected to the same bridged network. Then the voip client will connect to another AP when it looses the signal from the first AP. How fast it will be depends on the VOIP device software.
The VOIP device will plug into the CPE, thus the VOIP device does not connect to the AP’s. So all I do is give all the relevant AP’s the same name and security profile. The CPE will automatically connect to the AP with the strongest signal. What will happen if both primary and secondary AP’s more or less transmit the same signal strength? Will the CPE constantly jump between the 2 AP’s? Don’t know if this may cause possible connection problems? It makes sense that there must be some kind of signal strength threshold before changing to another AP…
why will you have two APs of the same SSID on the same tower?
A mesh is where you have multiple APs scattered around the area, so that they cover the clients from all sides. When one goes down, the client will connect to another one.
Too close is when their signal is almost the same.
Edit: I have an idea for you. You can have two wireless routers in one location. The backup router will have it’s wireless card disabled, and have a script pinging the main router. When the ping fails, the script will enable it’s wireless card, making it the main AP.
The starting point of the project will be on a 100m tower. With this tower I can basically cover the whole city/area. Thats why I need some kind of fail over solution on this central tower.
Normis, I like your idea. Makes good sense with what I want to do. I also agree with you that the best place for a fail over site is NOT to be on the same tower. The chances of something bad happening to both the primary and secondary RB’s simultaneously on one tower is good - like lightning, power supply issues and so on. With this project, it will be difficult (and expensive) to build an additional base station.
Any other insight on my original post will be much appreciated.
I think it is better to sleep one or more night about your project. I don’t know about the expectaitions of your customers at the voice part. Normally they will switch over from an line bases phone network. They are accustomed the quality they got today.
We haven’t seen a VoIP solution that is fullfilling the feature need of business customers and give the realibillity of the PSTN. For private customers VOIP is o.k.
MT is a very stable and feature rich solution for high speed internet access but I think the demands of an hospital (for example) will not go convergent to an wireless solution in an unlicensed band.
normis … q? about this … is this 100 concurrent users per RADIO .. say on a 433AH … or .. 100 concurrent users period on a single 433AH whether you have 3 radios cards or a single radio card …
i’m looking to support eventually 150 wireless users …
I think 40 clients per radio is the peak if you want reliable connection . 30 should give a good space for bandwidth for each client.
But another question is related here if you dont mind Cillys … suppose i have a hotspot with the same configuration as Cillys mintioned, if i have 3 radios in one RB433AH i want the hotspot SSID to be the same in the 3 radios , but after 40 clients connects to the first radio a scripts will interrupt to switch all the new clients to connect to radio number 2 and so on for the third radio.
The idea is that i want clients to connect directly with one ssid and to not interfere them to choose from 3 different SSIDs and at the same time no speed degradation issue should appear “assuming the 3 radios at the same frequency or in other frequencies or channels”
The question is can i create a script to do so ? or is there any other methodolgy that i can’t figure does the same naturally ?
A solution , how about a script to enable ssid beacon just for one card at the beginning and after reach 40 users disable “hide” the ssid beacon , and enable it for the second and so on ?
But i think there should no space for failover or something in this situation ?
How about max station count = 40? will that make any extra clients switch to any other card available with the same SSID?. Haven’t tried it… just an idea.
Overall I agree with coplete2006 but with planning, everything is possible to certain extent. We have been running a large community network here for years now. There is a SIP backbone, anycast services, streaming, p2p, and other services so on and so forth. I believe that with the enormous number of backbone nodes we have reached the reliability of the network has increased close to the 3 nines but still i would not trust it for business use and it was not built for that in the first place. You have to carefully plan your deployment, set backup, upgrade and disaster recovery procedures. Be realistic of what you expect from 802.11, mix and match technologies and use wifi as an extension to your fixed network infrastructure. Think over what hardware you are going to use for your base stations and for your clients. Use robust architectures and put them to harsh tests. Test traffic, quality, weather conditions, user friendliness etc. Think over what will be your network policies and how you are going to guarantee quality to your customers. There are a lot of thinks to consider…
From my experience even 40 users/AP are a lot if you want to offer BW to internal bw hungry services (not just browsing). For voip, browsing and a download here abd there it might be OK.
but here in afghan … hard to do things proper … hahahahah
but back to why i was asking … i’m setting up a wi-fi AP/hotspot for the base here … were small right now …
but i want to have a decent infastructure to begin … with so later on .. upgrading the site will be relative easy …
with MT RB’s and such … so i’ll start out with the 433AH with 3 radiso … going to 3 120 degree sectors …
3 * 40 = 120 laptops … and normis already said 100 users on the 433AH is no problems …
will that make any extra clients switch to any other card available with the same SSID?. Haven’t tried it… just an idea.