This section will describe the configuration of 802.11 wireless protocols and best use examples.
Wireless capabilities of a router can greatly enhance the usability of your home or office network or provide a solution for industrial structures. Choosing the right device for setup can be a puzzle to inexperienced users. This guide intends to explain different parameters and suggest a thought process to not get lost in the vast selection of MikroTik routers.
MikroTik provides routers with interfaces in 3 frequency bands - 2.4GHz, 5GHz, and 60GHz. Each frequency band has its own advantages and use cases.
Nowadays considered legacy because of overuse, it is still the most widely supported band. If you have a wireless client like phone, laptop or another device, it will most probably support this band. Even IoT devices often support 2.4GHz band. Because of the lower frequency, the 2.4GHz band can better overcome obstacles, so sequentially it has a bigger range than a 5GHz device, but it also usually has smaller throughput (internet speed). Also, it can severely suffer from interference (noise) from other 2.4GHz wireless devices, because almost every home access point supports 2.4GHz band and it performs well through walls and over large distances also, there are fewer frequencies to choose from (3 non-overlapping). If you have many close neighbors (apartments, shared office building) chances are 2.4GHz band will be saturated and performance will be lower. This band can also be used for industrial links.
Usually, new phones and laptops also support 5GHz band. If your client device and router support 802.11ac (sometimes referred to as just "ac") it will be faster than the 2.4GHz band. 5GHz band has more frequencies to choose from, but also usually has a lower range than 2.4GHz band. If you have new client devices, your network will benefit from an ac router. The 5GHz band is also often used for industrial links, because of the big frequency range.
Currently, there are very few client devices (phones, laptops) that support the 60GHz band. However, it offers cutting edge solutions for industrial links. For example, if you have 2 points that must be connected at distances up to 1500 meters you will get a 1 Gbps duplex link. For example, one of the MikroTik products is called the Wireless Wire because it provides the same speed as 1Gbps wired connection, but you will need a clear line of sight to establish the link.
RouterOS software on MikroTik devices provides broad and coherent configuration possibilities. RouterOS software allows you to use MikroTik devices in many ways, for example, if needed, a "home access point" device can be easily reconfigured to act as a client or form a point to point link, if needed. The "home AP" is simply the default configuration, but it can be changed to whatever configuration you wish. That being said, it is best to use hardware for its intended purpose.
Home AP for phones and laptops
Before you determine the most optimal choice for your setup, you should answer questions like how many clients you want to connect, what range you should cover and what speeds you want to get.
More connected clients mean higher latency and smaller throughput. We recommend 20-50 clients per interface to reach the peak performance, depending on conditions the number of clients can go up to 100 and still work stable. If clients will need high throughput or data traffic is time sensitive it is advised to plan fewer clients per access point. Often it is beneficial to choose simpler access points but place them denser.
The range of wireless connections depends on many conditions. Some of those are antenna gain, transmit power of router and client device, interference from other devices, obstacles (walls, metal objects), router placement. An important factor to note is that all involved devices affect the achievable distance, meaning that no matter how strong and sensitive your AP is, a small phone will be limited by its own transmit power and sensitivity. One device is unable to cover large areas if the client devices are mobile phones. Usually, only a few hundred meters can be achieved and more AP devices are required to cover bigger areas.
- Antenna gain is measured in dBi and determines how narrow the beam is. The radiation pattern of 0 dBi (practically impossible) is of the shape of a sphere, 1.5 dBi - 5 dBi radiates to all directions almost equally but has some dents and sides where the signal will be stronger. > 9 dBi has an obvious directional radiation pattern. Antennas with higher antenna gain if properly positioned will reach further in the necessary direction.
- Transmit power measured in dBm or mW determines signal strength that is coming out of a wireless interface. Mobile devices usually have small transmit power to save battery power. Even if, for example, phone reports an OK received signal strength, the router may receive a weak signal from the phone.
- Interference from other devices increases the noise floor and it gets harder for the router to distinguish signal from noise, therefore, the signal must be stronger and client closer to the access point. Access points in the same frequency occupy the same air time decreasing throughput and increased latency.
- Some objects decrease (attenuate) signal strength while others reflect the signal. Usually, in buildings, you have to keep in mind walls and their thickness, floor, and ceiling, metallic objects, glass, and wood also attenuate the signal.
- Placement of access point also affects range. The access point shouldn't be covered by metallic objects or surfaces so the signal would have space to spread.
If speed is important, then you should choose a 5GHz wireless router with 802.11 ac support.
For other wireless antennas to connect (CPE to AP)
Often it is necessary to connect two or more points, like, connect buildings on campus or connect client homes to network, or establish a long link. MikroTik provides solutions in these situations too. In order to choose, you must know the distance, whether you have to connect two points (point to point - PtP) or multiple points (point to multipoint - PtMP) and what speeds you need.
Because in these situations we are dealing with directional antennas and big distances, you must keep in mind that alignment and line of sight are crucial. For small distances up to 1500 meters, we advise using 60 GHz devices which will provide stability and great speed. Also, in small distances, 2.4 GHz or 5 GHz devices with small antenna gain will do just fine, although, you won't get such speeds as with 60 GHz devices. For longer links antenna gain and transmit power should be taken into consideration. Higher signal strength will allow higher data rates which mean higher throughput. Choose your frequency wisely to escape interference with other wireless links. Keep in mind that in cities even above the roof there often is interference from neighboring 2.4 GHz and 5 GHz links.
PtP or PtMP
PtP and PtMP links differ in some areas. For PtMP you most probably will want an antenna with a wider beam also called - sector antenna. Such antenna covers a wider angle but also has less gain, therefore, less distance. Also in PtMP access point must have at least level 4 RouterOS software license. Clients or devices that are connected to the access point and devices in PtP link can have license level 3 and narrower beamwidth.
For higher speeds in short links, you must choose 60 GHz devices, in longer distances - 5GHz ac devices.
For controlling large networks of access points you can use AP Controller (CAPsMAN) (Controlled access point manager). All RouterOS devices can act as CAPsMAN servers, however, it is advised to use appropriate devices for the task, with higher CPU power and more RAM. All RouterOS devices with 2GHz and/or 5GHz interface and software level at least 4 can be CAP (Controlled access point) clients and connect to a CAPsMAN server. For controlling hundreds of access points, we advise using our CCR series devices. For controlling thousands of access point you might want to try using CHR or an x86 machine.