What is a wireless mesh network?
Creating a wireless mesh network is a long engineering dream that only recently saw the light of day. Traditionally, in order to create a large network, you would need a good Internet connection, a powerful router (preferably with wireless capabilities), a handful of repeaters and access points, lots of cables (or lots of powerline adapters) and a degree in the IT field or Engineering (to actually be able to create and maintain the sophisticated network).
This meant a big investment, the signal was unstable and with lots of disconnects. For example, inside a big house, the connection would be interrupted if you went out of the first Internet zone and you would need to reconnect to the second Internet zone.
The traditional way of creating a large network had the problem of continuity and stability (which could have been solved to a certain degree with lots of money). But, the better solution is the implementation of a mesh network.
A mesh network is similar to the traditional one, in the sense that you need a main Gateway router unit (a Gateway router is connected to the Internet through LAN, cable or DSL) and some other units (access points) spread around the house, the office, the hotel or even the city. The difference is that these additional units act as nodes, which communicate with each other, sharing the network connection between them so you get a larger area covered.
Additionally, these nodes have a series of proprieties, as they are not simply repeaters, but have the ability to heal the network in case a node fails (the closest node takes over the data stream, so no downtime or blank WiFi zones) and the network can self-organize, so when you add new nodes it understands that it can use them for the best and quickest route to the clients.
But that’s not all, the mesh network can also self optimize, meaning that the more nodes it has, the better it can route the information so there is less interference, more bandwidth capacity and it can also serve multiple devices at once without affecting the network’s performance.
If that’s not enough to make you fall in love with this technology, let’s see some more reasons to implement a mesh network.
Reasons to implement a mesh network
1. It’s far cheaper.
The wireless mesh network systems are generally considered to be less expensive, the reason behind this claim being that you don’t have to install wires and that the mesh devices cost a bit less.
It’s true that you don’t have to install wires around your home or office, which will most likely mean that you would need to call an electrician or rely on powerline adapters, but some mesh routers may cost surprisingly more than expected.
For example, one of the more popular WiFi systems from Eero costs just as much as a high-end AC1900 router with MU-MIMO technology implemented (a single unit). Thankfully, there are better alternatives from Open Mesh (the OM2P-HS Enterprise), Luma or Ubiquiti that offer basically the same functionality at almost half the price.
2. It Can Handle Many Clients
As said before, a mesh network will adapt and reconfigure its path so it can offer the best WiFi experience. If implemented properly (the right number of units) this makes it suitable for city centres where there are lots of tourists, on stadiums and even as a global city-wide network.
3. It Works Well With IoT
The Internet of Things has become a rather controversial topic nowadays mainly because its security problems, but also because of the incompatibilities between different devices and a lack of a standard that will bring all the manufacturers on a common ground.
Now, how can the mesh network give a helping hand into the development of the IoT? You guessed it, it’s about the communication between the smart devices without the need of hub systems or computers. Obviously, it’s not only about smart houses, a wireless network system could be the future of a smart city, self driving cars and autonomous agriculture machines.
How To Implement A Wireless Mesh Network
Before going into this project, you have to consider a few things. First of all, before actually building the mesh network, you need a reliable Internet connection. This also means that you need to communicate to your ISP that you intend to create a larger network, especially if you plan to monetize your clients (you may need a business plan).
The second part is about the size of the network and if you want to scale it in the future. It’s obvious that if you have a large house, a hotel or some offices, then a single Gateway router placed in the centre with the access points gravitating around it should suffice (you can also add a good 8dbi antenna).
If you want to cover a larger area, then it is advisable to have at least two outdoor Gateway units pointing at each other (ideally, they would be within a clear line of sight, even if we talk about miles in between) and the nodes spread around the area. If there are buildings or hills that obstruct the signal, you need a larger number of access points but this is fortunate because the mesh network has the cool capability of using the nodes in order to go around the obstructions (instead of attempting to radiate through them).
The third part is about choosing the proper equipment. Similarly to common wireless repeaters, the first node that will be connected to the Gateway router will have the speed cut in half. The second node that connects to the first one, will have the speed cut in half again and so on, the last node will have a very low throughput (and let’s not forget about environmental interferences and network latency).
Now, let’s assume that we have equipment that uses a single radio and a single channel. For a few added nodes, everything will be fine, but as more units are added to the network, the latency will increase to such a state that the Internet connection will become unusable. This happens because a larger number of access points using a single channel require a larger bandwidth for the backhaul traffic to be repeated, so the wireless clients are left with less.
For those who are unfamiliar with the terminology, the backhaul traffic refers to the process of getting the data from an end user to a node and vice-versa.
Obviously, a single radio mesh network will be cheaper and easier to set up and maintain. If you don’t intend to create a small city-wide or a neighbourhood mesh network, this solution should work (for a small terminal or a small hotel) and if the network performance is still low, it will definitely help if you have more than one Gateway node.
But, you can take advantage of the real power of a mesh network by having a multi-radio, multi-channel network and a considerable amount of nodes. Most of the modern technology will deliver this setup, so the backhaul traffic and the wireless clients are being served by different channels. This means that the nodes will retain a larger percentage of the throughput and the network latency will remain low.
After you have decided which type of equipment you want to use (the AC-standard is preferred, but a mix between 802.11n and the 802.11ac standard is also not a bad idea) and the area you want to cover, it’s time to get to work.
If the system is indoors, then everything is quite simple, you connect the main unit to the Internet and spread the other units all around the building. Afterwards, all you have to do is use a controller so you can configure and maintain the network (it’s paramount to limit the access to illegal websites, especially if the WiFi mesh network is free to use by anyone).
I would recommend the CloudTrax from Open Mesh simply because it’s free, extremely easy to use and you can install the Open Mesh software on any old device that has an Atheros chipset (there are other controllers available on the market, but most require a monthly payment).
If you decide to create an outdoor mesh network, then you have to come up with different ways of connecting the mesh units to a power source. The main units should have powerful antennas (8dbi at minimum) and it should be installed on rooftops (you also need lightning protection), so there’s a bit of manual work. The zone where you install the Gateway units can be rented or you can come up with an agreement that allows free WiFi for the people who live in that house.
The access points that will have to be spread around the larger area can be installed on poles (again, you may need to rent that zone) and hook it up to electricity or use some small solar panels to power up the unit.
These are pretty much the basics of what a mesh unit is, how it works and how to implement one on a small area and scale it to a larger one. It’s clear that this technology is still struggling to reach out of its infancy state, but this is without a doubt the future of the wireless networks.