in the process of planning out a system to blanket a campground with MT hardware, and setting up a mesh network. loking at using 900 MHz cards to backhaul the signal to the main office where the internet connection is, but have a few questions about setting up the nodes. first, are there any good guides on setting up a mesh network with Mikrotik Hardware, and secondly, I will be installing 2.4 GHz cards in each node so that the campers can access the network directly from the wifi in their laptops / handhelds. was planing on using 2.4 GHz omni antennas vertically polarized, but was wondering if horizontally pollarized antennas would be better for this application. What is the typical polarity of a laptop?
the next big question is given this is a mesh network, and I won’ thave LOS to the office, how many hops can I safely run until it’s back to the central location (where the internet is) and what does increasing the # of hops do to the available bandwidth as far as mesh networking is concerned.
typical polarity for a laptop is semi-vertical (the antenna is usually in the lid and you have your lid at an angle when working). but that’s mostly irrelevant as the signal will have bounced a few times before it reaches your AP so a vertically polarised omni is ok. I’d stick to 8dBi omnis or even less as you don’t want to “overshoot” with the signal.
You can go as many hops as you want as long as you have point-to-point links between your “hops”. Basically you’d be using up all 3 slots of your routerboard, one is uplink (toward your internet link), second is omni (for laptops to connect to) and third is downlink (to another “hop”/routerboard). And that’s that really.
If you “mesh” them with a two cards (one 900mhz omni for both up and downlink and one for laptops) then you have to plan on halving the available bandwidth for each additional hop. So basically if you have 4 hops, laptops on the last hop would have one quarted of the available bandwidth as do laptops connected to the first hop. That’s why it’s a much much better idea to go with all 3 cards, uplink, omni, downlink. That way, theoretically, you have your max bandwidth at the last hop.
Thanks for the advice… I was planing on 2 900 cards per node to keep bandwidth available… the next questions is Channel layout. what do you suggest for that? I have been working with wireless for many years, but never done an installation where the nodes are 200 ft appart, so how should I layout the channels?
no hard and fast rules there as it’s all trial and error really. try each channel, test, switch to another, test, compare, switch…untill you’ve found what suits you best.
is there a reason why you’re going for 900 instead of 5ghz for backhaul? 5 will give you more bandwidth. I see 900 where you absolutely cannot get any sort of line of sight, but since you are doing multihop I’m sure you’ll be able to find some better spots to position your antenna. Or even 2.4ghz for backhaul is an option since you’ll be using panels or grids your antennae won’t be picking up too many neighboring wlans. And 200ft apart doesn’t really warrant the extra expense of going for all-900 gear, to be honest. Try 5ghz first.
the area is heavily treed, so that’s why we were going for 900. we did some tests with a pair of 5 GHz cards, in RB433AH boards, and couldn’t get decent connections out of them… when I was talking about channels I wasn’t referring as to which one to use, but with the nodes being close together and only 4 900 ch’s to use, how are they layed out? each node on the same channel, or keep nodes next to each other on different ch’s but reuse the channels say 2 hops away..