From a WISP point to multipoint radio perspective, pure mesh is a really bad idea (due to half duplex medium and CSMA hell).
I admire the internet research work that APNIC does but it looks to me like they're re-inventing the wheel here, versus mature and stable, relatively low cost commercial 5 GHz band point to multipoint radio platforms like the Ubiquiti Rocket5AC gen2 and its associated CPEs, Cambium PMP450/PMP450i, ePMP series, and the various 802.11n and 802.11ac based Mikrotik solutions for point-to-multipoint 802.11 based last mile. Or Mimosa's 802.11ac based 4x4 MIMO platforms.
If you want to have a community WISP that operates with purely open source software, and are willing to forgo running an OS you can mess with on the radio itself, there's nothing stopping you from doing all of your network management and backend operational software on purely GPL, BSD and Apache licensed software.
There are significant performance advantages to using a 'mature' commercial WISP PTMP radio platform, one example of which would be:
1) ubnt rocket 5ac gen2 radios
2) RF elements 30, 60 and 90 degree horn antennas
3) ubnt powerbeam AC ISO gen2 CPE radios.
The PDF spec sheet for this apnic thing shows that it's running on a 7-year-old 802.11n based chipset, functionally equivalent to 802.11n cards I could buy for Mikrotik routerboards in the year 2011, best possible modulation is 64QAM 5/6, while the current generation of PTMP radios mentioned above are all capable of 256QAM (much better bps/Hz in a given TDMA channel size like 20 or 40 MHz) and are 802.11ac or 802.11ac wave2 based.
One of the problems with mesh is that you end up with antennas that have very, very spread out RF patterns, because every node needs to talk to multiple neighbors. It ends up crapping all over the 5 GHz noise floor in a given area, and eventually becomes a CSMA nightmare. Whereas if you have a system with focused, shielded sector antennas for AP sites (or horns), and directional parabolic dishes for client antennas, you can scale to a much greater degree.
Dedicated purpose WISP PTMP AP radios like the Mimosa also adapt 802.11ac chipsets to the unique timing, timeslicing and TDMA contention problems of having many individual clients, with different RSL levels and modulations, at varying distances located many kilometres away from an AP site. Using an off the shelf 802.11n chipset will have significant performance issues. All major PTMP AP radios nowadays have a built in GPS receiver for the AP radio, and 'slave' the CPE radios to them to coordinate timing. This greatly increased the aggregate throughput (in Mbps) and capacity of a single AP radio and sector antenna. This means that you cannot connect a generic 802.11n or 802.11ac client such as a laptop or tablet to a ubnt airmax or mimosa gps-synced radio system, and that's an intentional part of the design.
If you want a mesh for resiliency, a common topology is to connect various AP sites together for backhaul purposes by dedicated point-to-point links (again with tight RF pattern parabolic dishes, or something like the rf elements ultrahorn, or licensed band radios), put a router at each POP, and form a "mesh" at layer 3 with common OSPF and BGP network topologies in a private AS.
Your half-duplex points literally do not apply to the librerouter. It has 2 separated 5Ghz radios and a separate 2.4 for local access.
Before you tell others how to build the network they already run, you might take 10 minutes to find out that they've managed to serve otherwise unconnected individuals and communities in remote parts of Argentina.
Sure, this isn't cutting edge tech, but it's cheap, scalable, and easy to upgrade. If you want to help these projects, you can find a 802.11ac chip with FOSS drivers. Until that happens, their hands our tied. Sorry not sorry.
I'm sorry but you're grossly mistaken, the very nature of 802.11n based radios is that an individual (typically 20 or 40 MHz wide) air channel is a half duplex medium. I'm talking about each individual radio in the unit. The multiple clients connected to each AP-functioning radio are sharing a half duplex medium. I'm well aware of the existence of 802.11 (abgn/ac) based radios that have multiple independent air interfaces in them.
You may wish to familiarize yourself with CSMA and listen-before-transmit issues, hidden node problems, etc in any half duplex air medium. I do this for a living.
It's completely disingenuous to say that because some single board computer with multiple minipci slots has multiple 2.4 and 5.8 GHz radios mounted to it, linked to different things over their 802.11n air medium, that it's a "full duplex" radio. A full duplex radio by industry definition is something like a FDD-LTE implementation for PtMP, or a point-to-point FDD radio such as in the licensed 6, 11, 18, 23, 71-86 GHz bands, in which a pair of radios listen and transmit in a high/low pair of totally separate channels, dedicated to traffic each direction.
I'm not telling people how to build their network. I'm sure this equipment is functional and providing service somewhere. I'm trying to prevent people in the year 2018 from chasing down dead ends of 8-year-old technology that will not be the most effective use of their time, effort and money.
It really doesn't rule out all AC equipment, quite the opposite, mikrotik PTP and ptmp radios and small routers are wildly popular in developing nations like the Philippines, Pakistan and Nepal. People on very limited budgets do some highly creative things.
Indoor wifi is a very different thing from a ptmp AP radio that might have clients from 400m to 9km connected to it, at a variety of signal strengths and some with fresnel zone incursion. The GPS timing systems used in the radios I mentioned previously make a big difference. For wisp last mile stuff it's also possible to do things you wouldn't expect in a office or conference high density wifi setup, such as allocate 75% of the timeslices to traffic in the downstream direction, because that is the typical traffic pattern of residential singlehomed end users.
What's the use for these kinds of wireless networks? I've seen wireless networks in big campuses before and it's just a bunch of APs that sit on their own VLAN that talk back to a controller sitting a telco closet somewhere else. They just plug into the wall so the only wireless part is the connection between the user and the AP but these kinds of things seem like they are meant for a different use case.
Rural broadband, primarily. Places where there is no DOCSIS3/3.1 coax cable, beyond any reasonable copper loop length for ADSL2+ or VDSL2 over old POTS phone wiring, and the only other option is a small satellite terminal. There's hundreds of WISPs all over the US operating in their own little pockets of service area. Rural parts of eastern Oregon and nothern Idaho for instance.
High degree of venn diagram overlap with the same customer market for the SpaceX Starlink system if it does become a concrete reality.
Since you have experience with WISP, I’m personally curious, for communities that are poor, but have low labor costs at certain points of the year, would a fiber backbone be viable?
I mean if labor for wiring was free, and you only have to pay for equipment and to configure the equipment, would it be worth it?
Although I think the communities would be grateful for just 200 kilobyte/s reliable internet on sunny days.
The lowest cost per km for FTTH (whether GPON based or active-ethernet) is 100% aerial on wood utility poles. Or in a developing nation environment, on the low rise height steel lattice tower utility poles that are used for the last mile electrical grid in cities like Lahore or Dhaka.
If I had a literally unlimited supply of labor to dig trenches and install cable, sure i could do underground FTTH at low cost. But manual labor to do cut and cover trenching, even with direct burial fiber, is going to be REALLY slow. What scale/size of project are you imagining?
Ideally all the unemployed males during the dry season would volunteer for the sake of their community. So maybe a few dozen men running fiber in a region where power is provided by local generators, solar panels, and fuel oil trucks.
So, the infrastructure isn’t even there, and the central government doesn’t care about any road side construction.
You would need literally hundreds of people with shovels and pickaxes to equal the meters-day of a tracked trenching machine digging a one meter depth trench...
I admire the internet research work that APNIC does but it looks to me like they're re-inventing the wheel here, versus mature and stable, relatively low cost commercial 5 GHz band point to multipoint radio platforms like the Ubiquiti Rocket5AC gen2 and its associated CPEs, Cambium PMP450/PMP450i, ePMP series, and the various 802.11n and 802.11ac based Mikrotik solutions for point-to-multipoint 802.11 based last mile. Or Mimosa's 802.11ac based 4x4 MIMO platforms.
If you want to have a community WISP that operates with purely open source software, and are willing to forgo running an OS you can mess with on the radio itself, there's nothing stopping you from doing all of your network management and backend operational software on purely GPL, BSD and Apache licensed software.
There are significant performance advantages to using a 'mature' commercial WISP PTMP radio platform, one example of which would be:
1) ubnt rocket 5ac gen2 radios
2) RF elements 30, 60 and 90 degree horn antennas
3) ubnt powerbeam AC ISO gen2 CPE radios.
The PDF spec sheet for this apnic thing shows that it's running on a 7-year-old 802.11n based chipset, functionally equivalent to 802.11n cards I could buy for Mikrotik routerboards in the year 2011, best possible modulation is 64QAM 5/6, while the current generation of PTMP radios mentioned above are all capable of 256QAM (much better bps/Hz in a given TDMA channel size like 20 or 40 MHz) and are 802.11ac or 802.11ac wave2 based.
One of the problems with mesh is that you end up with antennas that have very, very spread out RF patterns, because every node needs to talk to multiple neighbors. It ends up crapping all over the 5 GHz noise floor in a given area, and eventually becomes a CSMA nightmare. Whereas if you have a system with focused, shielded sector antennas for AP sites (or horns), and directional parabolic dishes for client antennas, you can scale to a much greater degree.
Dedicated purpose WISP PTMP AP radios like the Mimosa also adapt 802.11ac chipsets to the unique timing, timeslicing and TDMA contention problems of having many individual clients, with different RSL levels and modulations, at varying distances located many kilometres away from an AP site. Using an off the shelf 802.11n chipset will have significant performance issues. All major PTMP AP radios nowadays have a built in GPS receiver for the AP radio, and 'slave' the CPE radios to them to coordinate timing. This greatly increased the aggregate throughput (in Mbps) and capacity of a single AP radio and sector antenna. This means that you cannot connect a generic 802.11n or 802.11ac client such as a laptop or tablet to a ubnt airmax or mimosa gps-synced radio system, and that's an intentional part of the design.
If you want a mesh for resiliency, a common topology is to connect various AP sites together for backhaul purposes by dedicated point-to-point links (again with tight RF pattern parabolic dishes, or something like the rf elements ultrahorn, or licensed band radios), put a router at each POP, and form a "mesh" at layer 3 with common OSPF and BGP network topologies in a private AS.