Mesh Networks — Improving Wi-Fi Access And Connectivity
By: Vincent Tabora
Tags: Wifi, Internet, Network, Technology, Wireless

If you have property with more than 1 floor, a basement, an attic and a large area (> 3,000 square feet), getting Wi-Fi access can sometimes be a challenge. The signal coming from a wireless router can be limited to a short distance (common with 5 GHz signaling) and cannot penetrate through thick walls. As a result, it would require users to either be in closer proximity to the router or use wireless repeater (also called range extender) access points.

A townhouse, mansion, warehouse office or large estate would usually come to mind. It is often difficult to get Wi-Fi access because of the distance the signals need to travel. There are also many obstacles that can block the signal and reduce its strength, so users are not able to get reliable Internet. In most cases, you can get a much stronger cellular network signal (e.g. 4G LTE) for Internet access. That can be quite expensive for users on a limited data plan with their network.

Mesh networks provide an ideal solution for that problem. A mesh network uses multiple devices for Wi-Fi access rather than just a single router. The devices are interconnected with one another, and provide access to the network all throughout a location. This allows users access to areas where the signal from a single router could not reach. It still supports the current Wi-Fi standards like 802.11ac dual-band (2.4 GHz, 5 GHz) or 802.11ax (Wi-Fi 6). The communication among the nodes and the router can use a different radio channel.

Figure 1. A mesh network can support multiple devices across a large space. It is ideal for connecting IoT devices in smart homes and offices.

Wi-Fi Connectivity Issues

Some have tried BPL (Broadband Over Power Line) with good results. The BPL device connects to the router and transmits the signals using existing power line circuits. However in larger setups, BPL may not travel the entire grid to deliver data signals. This is because the signal transmission can be affected at some point in the circuit. These are due to transformers in the signal’s path.

Figure 2. It can be frustrating trying to get a good Wi-Fi signal when you are far away from the router. (Photo Credit by Yan Krukov)

Wireless repeaters are often used to extend a wireless router. The problem is that repeaters can be intermittent at times. Since they were originally designed to repeat a signal to reach the user, it can be affected by external sources. What they do is just extend the signal from a wireless router. The signal’s strength is not preserved, and it can degrade due to obstacles that can hinder the signal (e.g walls, floors, ceilings, metal, concrete) and also from electromagnetic interference (e.g. radio signals, microwaves).

Mesh Networks

Mesh networks offer a better solution. By using beamforming, Wi-Fi signals can be concentrated using antenna arrays to deliver more signal to the device rather than radiating outwards which weakens the signal strength. This is not exclusive to mesh networks alone. Beamforming is also used in 5G networks, to transmit signals between small cell site antennas at a distance of not less than 500 feet apart. There are other Wi-Fi implementations that use beamforming. This improves the transmission of signals which means more reliable bandwidth and faster speeds.

The main purpose of a mesh network is to provide consistent wireless coverage. In a mesh network system, there can still be a main device that functions as a wireless router. This is where the Internet connection is coming from. The signal from the main device is then sent out to satellite nodes, which provide a hop to other nodes to provide a strong Wi-Fi signal. Users then connect to the node that is closest to them with a boosted signal as if they were right next to the actual wireless router.

Figure 3. In a mesh network topology, each node n is connected to every other node (n — 1). For 5 nodes, each node has 4 connections c. The entire network has a total of 20 connections (n² — n / 2) or n * c. From the diagram you have a total of (n * c) / 2 lines of communication or 10 lines. If one node were to go down, you still have multiple paths to access the network.

The mesh network uses an ad hoc topology. In this setup, it does not require a centralized access to the network. The original architecture was meant to be decentralized, so that if one node goes down the network can still function. Retail mesh network implementations are ad hoc, but not fully decentralized if it requires a main device for the Internet. Each node can access the Internet independently, so it is decentralized. However, this still requires a main device to provide the Internet on the mesh network.

Figure 4. ZenWiFi AX (XT8) mesh network system (Source ASUS)

The connectivity among the satellite nodes relies on self-healing algorithms (e.g. Shortest Path Bridging) which provides awareness of when a connection is broken. The nodes can re-route signals and allows the user to discover other nodes to connect to. A typical setup (e.g. Asus ZenWiFi AX) would consist of just 2 satellite nodes. It then requires connecting one of the nodes (i.e. router) to the modem for access to the Internet. The other node is then configured to communicate with the router and users can access the Internet.

In terms of security, a mesh network system can provide features to secure the network and communications. With Wi-Fi 6, enhanced security can further be provided. Vendors often target the market for smart homes and offices, so this is an important consideration. These include devices like intelligent thermostats, smart refrigerators and a vast line of IoT (Internet-of-Things) devices. These can be vulnerable when connected to a network, so mesh network systems must provide the best security to prevent cyberattacks.

Synopsis

Mesh network solutions boost and extend the signal, using a distributed and decentralized network of satellite nodes. The entire system acts as one network, not individual access points that require a separate passphrase. The user can connect to any node to get access to the Internet with a strong Wi-Fi signal. In terms of setup and configuration, mesh networks have become easier to install with smartphone app based management. When it comes to speed and performance, it will be up to the protocol (e.g. 802.11ac, Wi-Fi 6) and number of bands (frequency channel) that the system supports.

Since access to the Internet is an essential requirement in daily life, it becomes necessary to provide that service. While it is easy to connect to Wi-Fi access in your typical small office and apartment, the challenge becomes greater when you have a larger space (e.g. multi-floor units, large offices). These include business centers, shared workspaces and mansion estates. Wi-Fi signals can get lost and degrade with distance. A mesh network environment provides consistent signal coverage that handles larger areas for Wi-Fi access.