topology considerations, dublicate channel, dust-resistance

Dear all!

My goal is to project and build a wireless network for 7 factory buildings (500 meters between each maximum) on a territory of a plant producing technical carbon (which gives a high level of carbon dust|powder in the air and on all surfaces). On a scheme below:

all 7 buildings in subject are marked with red and the “С” shaped building at the bottom of the picture should be a central node of the network, where all data flows should be directed.

My questions are:

  1. As the data model is star, considered topology is also star, with the heart of it at the central node. But as we can see from the picture the central node is not the highest (and closest to other) building, thus No line of sight to at least one node (small building at the highest point of the scheme). The Pipe Plant is the highest point of course, but if the “heart of a star” node would be placed there, it must be connected with a central building with a very high speed backhaul repeater(at least 40 mbps for each peripheral link x 6 buildings = 240Mpbs)?? Or we can simply put a repeater for just one link between the top building on a picture and the bottom one. Need a suggestion about topology.

  2. Since we need high performance (at least 40 Mbps from each building to a “heart” node) AND failover option, a solution have been proposed to duplicate (even triplicate) each link from a heart node of a star to a peripheral nodes. Question: if we will setup 2-3 concurrent links in star topology, what would be the most economical tecnique to balance the load between them? How would it correlate to mesh technology?

If I simply insert 2-3 r52n into the routerboard, I probably will be able to play with routing(?) to split bandwith between LIVE links to support failover. Is there any Router OS solution for load balancing and failover? If 2-3 r52n link will act concurrently between two points, will it cause interference? - I belive there is 20+ channels is 5 Ghs..


Or are there any economical solutions (no CISCO etc..)?

  1. Have anyone dealt with carbon powder in air? Proposed solution - backup everything related to wireless. Would that be enough?

  2. Is there any sence in using a repeater with multi-radio for a “repeater”, placed on a building in a center of a picture to connect the building at the top(peripheral node) and bottom of a picture(star “heart”), since both are NLOS?

  3. Will several of r52n’s coped with a routerboard be a good solution? Will r52n support 300 Mbps?
    Antennae? Any suggestions on equipment..

  4. What N equipment can you suggest may be of other make? Rocket M is faster than r52n?

fiber? why not?
For failover you could use ospf.

OSPF, or maybe HWMP+ ?

http://mum.mikrotik.com/presentations/PL10/hwmp_interprojekt.pdf
http://tiktube.com/?video=341

Dear all!

  1. Which one is better:
    OSPF or HWMP+ . Have read both, but haventg been able to realise the answer.
    Which is better suited for the situation above?

  2. Will there be an interference between the links, I we will use several concurrent R52n to r52n wireless links connecting the same noides?
    Is it possible to divide them at the channel level, will there be an interference?

  3. Should all R52n’s be bridged?

  4. What is the main difference between R52n (r52Hn) and XR71 from Ubnt? They are both MIMO capable, but pricing is 3x more expensive for XR71..

Thank you for the assistance.

which one is more suitable: OSPF or HWMP+ ?
for this particular situtation..

here is a model:

Uploaded with ImageShack.us

Questions are:

  1. Is it possible at all to share a 90 degrees sector between 4-6 parabolic 802.11n emitters in a radio clean environment (in a woods)? Does anyone had a similiar expirience?

  2. How many “N” routers (MIMO, with paired antennas) can we put into such a limited sector?

I am talking about RouterBoard with a couple of R52n..

HWMP+ is layer2 forwarding protocol it is used instead of regular bridge.

OSPF is layer3 routing protocol which is not the best choice for large wireless networks.

You have to decide whether you want ip routed network or bridged network.

Thanks for the comments.. Will these APs interfere with each other? Lest say, we are limited just to 2.4 only.. What do you think how many APs can we fit on a 2.4 Ghz range into a 60-70 degrees sector?