When your mesh WiFi isn’t mesh

Do you long for mesh wifi or already have them? Well look further as most mesh wifi products out there are rebadged wifi extenders. Recently where I work upgraded their ISP and got 2 different types of mesh WiFi APs in pairs. The problem of mesh WiFi has been something I mentioned long ago on snbforums (small net builder, I highly recommend them for computer networking advice). In order for a WiFi to be mesh it must fulfill certain criteria.

Mesh WiFi is essentially a lot of WiFi access points interconnected with each other. These access points can allow traffic to pass through them just like a bunch of interconnected switches. Mesh networking is a real thing and some wireless based networks are truly meshed while you could imagine the internet as a gigantic mesh of nodes.

A WiFi extender however extends on another WiFi’s signal, it only sends traffic back and forth between defined APs using the same radio. Unlike mesh, WiFi extenders use the same radio to communicate with their counterpart access points as they do to communicate to their connected clients. This effectively extends the range of the base WiFi access point but at the serious cost of speed. Mesh is impossible here because the speed penalty makes it impossible to pass traffic through a theoretically large network of WiFi access points all interconnected with a random bunch of them terminating to another network and some only in between.

In a mesh WiFi network, the WiFi access point has additional radios for dedicated inter ap communication. One similarity I can make which has finite limits is the many core mesh architecture of the TILE Tileragx processor line, having so many cores at its time where most processors couldn’t even come close especially at its price point. Facebook used them a lot as they sped their servers up by offloading scalable tasks of their CPUs to both tilera servers and tilera add in cards. These CPUs used an interconnecting mesh on 2D that allowed intercore communication, but this mesh of connectivity could be brought down by too many transfers even with low amounts of actual data. Each node under the core had limited capacity to number of transfers rather than data but each core could perform its task unhindered. Similarly in mesh WiFi, each node could have a network termination or exit to another network or be an isolated point relaying to another until the network packet reaches its destination/exit.

This means that for mesh WiFi to work, the ability of the access point to give WiFi to its clients must not be disturbed by the WiFi it uses for mesh which can only happen if the device has a dedicated radio for it. This lack of dedicated radio for mesh makes the setup/device not a mesh WiFi AP despite many products claiming so. In the past wireless ISPs would create their own mesh manually using 2-3 access points at each node. Each node would consist of one access point with omnidirectional wifi to talk to clients. This access point is then wired to a bunch of other access points that each use directional/dish WiFi to pass traffic wirelessly to other nodes until it has reach its exit or destination device. The gateway could be a few hops away and this method does work and is still in use even by some commercial ones that provide it to homes. Some however will reserve a portion of airspace for mesh and dedicate a small portion of that frequency space to the client in these non WiFi standard based wireless internet networks such as usage of the old TV antennas meaning that despite potential bottlenecks, the client’s communication between the node and itself is never interrupted. This is the main difference between WiFi extenders and mesh WiFi which cannot be noticed without measuring performance between 2 clients connected to the same node communication with each other.

An example WISP node with many directional access points, some are used to communicate with clients while some are dedicated to connecting with other nodes. This node could be wired to an internet line or be an isolated wireless node passing traffic to and in between other nodes.

In an infinite mesh of nodes, how do we know the most efficient way to route where any could be connected to a gateway or not? Most “mesh” WiFi products do not address this problem and are just dumb extenders

So a few things that make a WiFi AP mesh capable are:

  • Dedicated radio to communicate with mesh network and not clients
  • Load balancing clients between APs based on criteria like signal and bandwidth
  • Seamless switching between different APs
  • Mesh network protocols to form mesh network and determine best paths

That free mesh WiFi AP your ISP gave you, or even one you got from offers may not likely fill all the above criteria. You need to fulfill all the above criteria to be considered as mesh wifi which most that call themselves so simply lack the first criteria. For instance we got Deco mesh from out ISP. Not only was its signal so bad that it could be seen by the next building in sight, it would not penetrate the stair + lift corridor in the middle. This poor signal design with highest signal tx power made performance so bad that all its good for is to extend the signal not provide a meshed WiFi network. It didn’t even allow me to configure it easily breaking protocols and sop in business when another admin may need to access it. Airties faired much better addressing the lackings of Deco but still did not have a dedicated radio for mesh. Our ISP explained that these overheat but so far we have not had that issue. These devices are also given in pairs so most likely will not work beyond must 2 devices. Hence maxis, tplink and airties you cannot call these devices mesh WiFi as they lack the basic functions a mesh network requires. These are simply WiFi extenders in disguise that I just set up as regular APs as no way will they withstand 20 people hitting them at once in their “mesh” mode.

Deco and airties for example are meant to extend rather th

With lack of policing and rules, manufacturers are jumping on the bandwagon when their devices simply aren’t mesh WiFi, tricking unsuspecting users that will never know they have a plain old cheapo WiFi extender and not an actual mesh WiFi. I pity those that bought these to stay up to date, for bragging rights or even to set up an actual mesh network. We need actual metrics to be able to say if a device is mesh WiFi or not.

extendersmeshWiFi