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Wide area network - advice

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KN4MDJ
KN4MDJ's picture
Wide area network - advice

Hi all,
I'm thinking of making a mesh that covers about 150 miles, using a dozen 200ft ham towers (one 400ft) around the area.
Area is central Florida so very flat. Existing vhf repeaters at this height have about 20 mile ranges.
Towers are spaced 10-20 miles apart, the hope is that we could make a mesh that would cover a good chunk of central Florida that "all we'd need is a small dish to aimed at a local tower and be on a large network".

In my professional work I played with a 20 acre wifi project using TP-link CPE710's (as the AP's) and looks like they are just getting added to AREDN.
The beamwidth width is about 7 degrees with their reflector ears but without them seems to be about 45 from my experience, I'll need to do a test setup on a tower to verity their angle and distance range. 

So here were some ideas.
Initially, put 4 or 8 AP's in cardinal compass directions on a tower, running a ethernet cable from each to ground, to a smart switch and local router.
That way all the expensive hardware is on the ground and can be easily changed as needed.
Alternative would be to put a smartswich up at the access points and run a power and lan cable down to the ground to the router.

Originally I was thinking of doing as an infastructure setup, with each tower being a large bridged AP with dedicated uplink dishes to known towers, but...
then we have AREDN that might be more useful since a tower may be able to see others and offer multipath redundancy.
My concern is that if the backhaul and users are sharing the same 'sectors' those speeds will default to slowest user.
For ID's I was thinking of using their grid square and direction.   XXX-EL98fw-NW
If there was a second SSID that was common, users could hop from sector to sector and tower to tower?   XXX-Common
Could ARDEN handle the hand-off, I know it wont be like cellular but if the break is short enough downloads may continue.


Thoughts?
I know some users have a disdain for TP-Link, but they are moving in to the pro market with their Enterprise line and Omada cloud.
(practical clone of some ubi equiq)  this units rating is   23dBi ,  -27dBm

Ken, KN4MDJ / wb4sa

nc8q
nc8q's picture
Local success, mesh failure:
"Thoughts?"

Locally, by mid 2017 our area's attempt at building a 'mesh topology AREDN network' was a bit of a failure.
I mean building the network was a success. It was having it function as a network failed.

Failure:
There were 32 nodes on channel '-2'.
Many hidden nodes and many exposed nodes.
As if any of each are not already too many. ;-)
Our sole 'node array covering 4 cardinal directions' has never had a user to link (ever, in over 8 years).
This system was rebuilt recently. Still not a single user has linked.
All downlinks installed with the expectation of
'if you build it, they will come'
has, to date, failed miserably.

Success:
High profile sites are now connected with point-to-point 5 GHz links.
All high profile sites with channel '-2' devices have their ability to link to each other on channel '-2' disabled.
i.e. Only user access on channel '-2' is encouraged.
We installed 5 GHz downlinks from high-profile sites toward existing/interested users.
Often the user provides devices with enough power and gain to achieve the link.


When you say 'cover 150 miles' is this linear?
I recommend using a tool to determine equipment needed to establish a link between the towers.
I recommend that you do not share user channels with backhaul channels.
When you say "For IDs" do you mean Node Name or SSID?
I recommend that users do not 'hop'. Actually, they cannot access services by 'hopping'.
I recommend that you build your network so that the AREDN firmware may/can/will be able to choose a valid path.
I recommend that you do not install nodes in 'willy nilly' fashion in the hopes that the
AREDN firmware will 'figure it out' !
I do not understand 'hand off'.
I recommend that you build your network in 'cellular' fashion.
" -27dBm"
Typo: dBm values are always positive. negative power ?

Your millage may vary.
I hope this helps,
73, Chuck

 
KN4MDJ
KN4MDJ's picture
Thank you for your insight.
Thank you for your insight. It's still in the initial thoughts/day dream stages.
Yes, linear 150 miles from furthest points, a sweeping 90 curve across the state from Tampa to DeLand.
So your advice would be to put AREDN on each tower for the clients to connect to, then use point-to-point, maybe bgp to connect the backhaul between towers (setup for multi-path uplinks). Sort of like our current SarNet (microwave backhaul with linked uhf repeaters on VOIP).
Was referrring to the SSID for the naming scheme. Still have to do equipment testing to see what the actual hardward range is for the point-to-point, and see if it's posible to link each tower.
 
AJ6GZ
A few ideas
-You only need a max of 3 nodes per tower, with 120 degree sectors on each tower. -For backhaul, point-to-point links without users on them are the only way to go. High gain, narrow beamwidth. This can be done with AREDN devices or if you already have a network you can use that. It's not necessary to run the AREDN protocol on the backhaul and there are some advantages not to... and some to do so. If you use your existing network, or make a new one with BGP or some other real protocol (not OLSR), you would connect AREDN nodes together via Tunnels (not DtD) in their own address space. If you can route IP between towers, a tunnel will work regardless of the underlying topology. We have a group in SoCal doing just this, using existing commercial microwave links. -It's best not to allow native AREDN protocol P2P links to see extra towers beyond their neighbor. OLSR has no way to pick the 'preferred' link beyond very basic, automatic non-tunable metrics, and you can end up with route flaps between 3 towers. Yes, sometimes it is necessary by geography or cost to have a tower take in two remotes on the same dish. It will work, but there is a performance hit (use of a TDMA style AP would help there). In short, as Chuck said, don't let the AREDN firmware "figure it out". Of course this is exactly what happens on a user-facing sector :) -While I prefer the MikroTik stuff, keep in mind there is no remote reset button on the ground like Ubiquiti on those 200ft towers. Yes, keep the switch and as much as you can on the ground. Also be aware of your downtilt angle at those heights. No experience with TP-Link here. -Pick one SSID, preferably the default one, and use it everywhere. User experience should be connect to the best tower/channel and go, no other configuration on their part should be needed. For backhaul, I haven't tried using a separate SSID but that might be possible to keep people off the wrong links. -Avoid 2.4Ghz. Should only be used locally by users, inside the house, or at a special event for exmaple.
KE0RSX
KE0RSX's picture
I will add this. Depending on
I will add this. Depending on how you plan to power the nodes, you *may* have a remote reset on the ground. If you use their individual power supplies, it has a remote reset in the adapter. But, if you use something like a PoE capable switch, then you lose that functionality.

I would say for the tower to tower, use something like a dish (LHG-series from Mikrotik or maybe one of the Beams from Ubiquiti). I don't have experience with any TP-Link dishes, so I can't give you a recommendation there. The alternative (albeit expensive) is to put three Rocket M5's (or most likely the M5ac series now) on each tower, with 120-degree antennas. That would give you the envelope around the tower, as well as potentially the links between. You can go to http://link.ui.com and set up different products from them to see what the bandwidth and capabilities are. If you want to use TP-Link, pick some of their Nanostations on the site, as those are going to be close to what the CPE-series looks like and has for capabilities.

I'll echo the avoid 2.4GHz nodes. And I would say get the ac class of nodes. Above all, plan it out before you buy or put up anything. We learned the hard way that not researching before we send a climber up is an expensive mistake to make.

Have a great day. :)
Patrick.
w6bi
w6bi's picture
Remote Resets
Just a reminder - Mikrotik doesn't offer the remote reset function that Ubiquiti does.
Unsure about TP-Link gear.
Orv W6BI
 

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