How to choose the best channel for WiFi networks

How to Choose the Best Channel for WiFi Networks

How to choose the best channel for WiFi networks


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How to choose the best channel for WiFi networks can be tricky. When deploying a wireless network, Network Engineers need to select the right channel to improve WiFi coverage and performance significantly. 

WiFi instability and signal interruptions are very often tied to the choice of the channel applied. Issues like reduced range or sudden drops in transfer speed are the mainstream problems of any high-density WiFi deployment. This, of course, might depend on the wireless environment in which a new network is deployed. 

Therefore, before designing and implementing WiFi networks, it’s essential to ensure that the impact between a network previously deployed and converging WLANs is minimized 

To prevent all these issues with your networks, when planning for the right channel, we suggest taking into account two key factors: IP and Channel plan.

What is the IP Plan, and how does it work?

An IP plan is a document developed by Network Engineers to show how IP addresses will be distributed among network devices based on network design to support the required services.

The IP plan allows you to:

  • Determine the number of IP addresses required to provide the specified services to customers.
  • Maintain reachability between the different network segments.
  • Facilitate future expansion and modification of the network.

 

The first aspect to check concerns the presence of IP conflicts. IP conflicts occur when two or more networking devices have the same IP address (layer 3) and can communicate within the same WLAN (layer 2). Thus, the sender doesn’t know who should deliver the specific IP packet due to the conflict. It is like if two units claim to be the receiver of the specific package, and there is no way to know who will be chosen.

Therefore, it’s crucial to know the WLAN’s design, how it’s partitioned into collision domains, and how many NAT levels are cascaded. The typical situation in an environment where a DSL router is installed is that such router has a WAN port with a public IP, dynamically provided by the ISP. An IP class is shared among all LAN ports, such as 192.168.1.1/24. It means clients connecting to the LAN ports will receive an IP address between 192.168.1.2 and 192.168.1.254.

In these cases, it is best to leave the added AP configured to work in DHCP mode (with dynamic IP), which means it will receive an IP address in that range, behaving precisely like other clients.

To know the exact IP addresses assigned to WiFi clients, you can check the DHCP Lease Table, available in the DSL router configuration tool.

If your DSL router has a WiFi interface, the same criteria must be applied, as the SSID is usually connected to the LAN ports and shares the same DHCP range. If you need to assign a static IP to the added AP, it’s important to check the DHCP range of the DHCP server built into the DSL router.

This operation is usually accomplished by logging into the web interface or DSL router configuration tool.

The static IP assigned to the new AP connected to one of the router LAN ports must not be included in the DHCP RANGE; otherwise, an IP conflict is likely to occur between the AP and a network client receiving that IP from the DHCP server.

The Channel Plan to reduce interference

A proper design and deployment of a wireless network must include a channel plan, pivotal for high-performance WLANs.

Whether you are using a static channel plan or a dynamic channel assignment, there are a few things to consider beyond choosing the best channel for that network. One of the most important is deciding the correct channel width to use.

The IEEE 802.11 standard defines wireless networks’ operation in the frequency ranges of 2.4 GHz and 5 GHz. (Learn more here https://www.tanaza.com/blog/5ghz-vs-2-4ghz/).

WiFi channels are the smaller bands within each WiFi frequency band. The 2.4 GHz band is divided into 14 channels (1-14), according to the standard and depending on the availability of each country’s regulations. Each channel could be up to 40 MHz wide. The two frequencies combined allow for channel width from 20MHz to 160MHz. Although, there are 14 channels available in 2.4GHz, and only 3 of them don’t “overlap” or interfere with each other: 1, 6, and 11. 

However, channels 2-5 interfere with 1 and 6, while 7-10 interfere with 6 and 11.

For instance, when a station (access point, or client device) needs to  transmit something, it must wait for the channel to be free. Therefore, only one device can send data at a time. When overlapping channels (2-5, 7-10 at 2.4 GHz) are in use, any station on those channels will transmit regardless of what is happening on the other channels, causing performance downgrade. This type of interference is described as Adjacent Channel Interference (ACI).

A Co-Channel Interference (CCI), on the contrary, occurs when two or more APs in the same area operate on the same channel. This essentially turns both cells (the coverage areas for an AP) into one large cell. Any device that has something to transmit must wait for the other devices associated with the same AP. But also wait for all the devices related to the other APs on the same channel. 

Indeed, CCI will also reduce performance even if not as severe as ACI. The reason behind this behavior is that multiple devices are attempting to access wireless media on the same channel, forcing stations to wait longer before they can transmit.

Due to the limited amount of available spectrum, it’s safer to use only non-overlapping 20 MHz channels, although the possibility to use 40 MHz was added in 802.11n.

In the 5GHz band, there is much more spectrum available. Each channel occupies its non-overlapping slice at 20MHz. As with the 2.4, 802.11n gave us the ability to use 40 MHz channels. From there, 802.11ac now allows 80 MHz and even 160 MHz wide channels. These wide channels are created by joining 20 MHz channels together, using the center frequency to indicate the channel.

So why not set your APs to the widest channel available?

Let’s assume we have decided to use 80 MHz channels for our deployment. We just went from 9 non-overlapping channels to 2. This means that half of the APs we have implemented will occupy the same part of the spectrum. Now, for APs on opposite ends of the facility that can’t communicate with each other too loudly, this isn’t a big issue. 

The situation changes for the APs close to each other. These APs and any associated devices become part of the same cell, slowing everything down. All devices must then wait their turn to access the network.

The best way to accomplish this is to have as many channels as possible to distribute. Even though a 20 MHz channel doesn’t achieve the higher data rates shown on 80 MHz, users can still achieve acceptable speeds.

For most enterprise-grade deployments with many APs, choosing narrow channels will give the spatial reuse you need for your WLAN to perform at its best and improve the user experience. However, the best practice is to do a quick survey and check which channels are already in use on-site to choose the right channel for your network. There are many free tools for Windows, Mac, Linux, to do this kind of process.

For example: in a venue with a WiFi DSL router in place, the site survey might provide the following result:

– SSID A / location 1 / channel 1 / power 4/5
– SSID B / location 2/ channel 11 / power 3/5
– SSID C / location 2 / channel 9 / power 5/5

In such a situation, the best channel to use is 6, which does not overlap with neighboring SSIDs. If possible, we suggest to turn off the WiFi of the DSL of the venue where the AP is being added and remove unnecessary interference. If this SSID is active, it should be considered as a source of interference.

For instance, Tanaza allows the band selection with which you can decide whether to transmit the SSID only at one frequency or whether on both frequencies (only 2.4Ghz, 5Ghz, or dual-band).

In the Tanaza platform, radio selection is automatically set to ‘standard channel selection’. However the user can edit it manually, allowing the individual radios to be turned off.

As the interference sources can change over time, it is recommended to use remote channel management tools to change the channel when needed. The Tanaza dashboard includes a tool to easily change the channel automatically.

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How to choose the best access point for your restaurant’s WiFi network (part 1)

How to choose the best access point for your restaurant’s WiFi network (part 1)

restaurant's WiFi network

Are you planning to deploy a new Wi-Fi network in restaurants? Read this article to find out the three main requirements for a successful Wi-Fi deployment.

When setting up a new Wi-Fi network, you need to make sure you choose the right access point depending on the environment in which it will be deployed and your project’s budget. As for Wi-Fi projects targeting restaurants, you need to consider the following aspects: the size of the network’s covered area, the number of concurrent users and internet usage.

 

1. Location size

 

The first step to consider is the size of your Wi-Fi network’s location: is the size of your restaurant big, medium or small?

On average, a large restaurant can hold from 80-200 people, a medium-sized restaurant from 30-80 people and a small restaurant from 10-30 people. Depending on the size of your venue, you will need to choose one or more access points to cover the area. Also, should your restaurant include a terrace or a small garden, consider that you will need to install not only indoor but also outdoor devices for your deployment. Check out the list of Tanaza’s supported access points: by being multi-vendor, Tanaza offers a wide range of devices, both for indoor and outdoor environments.

 

2. Number of concurrent users

 

Based on your location size, the number of concurrent users connected to your network will vary accordingly. The network of a large restaurant may host approximately a maximum of 30 concurrent Wi-Fi users, the network of a medium-size restaurant may host a maximum of 12 concurrent users, whereas the network of a small deployment will likely handle an average maximum number of 5 concurrent users.

 

3. Internet usage

 

Lastly, it is important to pinpoint what kind of online activity your Wi-Fi users will do while being connected to your Wi-Fi network. Indeed, some applications consume more bandwidth than others: for instance, the rate of data transfer in your network – measured in bits per second (bit/s) – will be lower when users message and chat on Facebook, Whatsapp or Telegram, check their emails and browse the web. On the other hand, a higher number of bits per second will be transmitted across your network when users share or download/upload pictures and files on Dropbox and Google Drive, stream Youtube and Netflix videos, make VoIP calls or video calls on Skype.

Read the second part of this article by clicking here!

Cloud management and splash page management for UniFi AP Outdoor

 

UniFi AP outdoor Ubiquiti Networks cloud management TanazaThe UniFi AP Outdoor includes two external antennas and a secondary Ethernet port for bridging.

It supports 802.11n MIMO, with speeds of up to 300 Mbps and a range of up to 183 m (600 ft).

Download the complete datasheet for this device (click here to download it – PDF format).

 

By making this device Tanaza Powered, you can:

  • Configure it from remote, cloud manage it, and receive e-mail alerts when the device gets disconnected
  • Create and assign up to 8 SSIDs  per AP and create a public hotspot with customized splash page
  • See real-time statistics

 

Click here to read the FULL FEATURE LIST of Tanaza powered UniFi Outdoor

 

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Wi-Fi stumblers complete list | Windows Mac Linux Android

Wi-Fi stumblers complete list | Windows Mac Linux Android

wifi stumblers

This is the most comprehensive list of 17 free and commercial Wi-Fi network stumblers for Windows, Mac, Linux, Android and iOS.

In this post, we will look at the 17 most popular Wi-Fi network stumblers for Windows, Mac, Linux, Android and iOS, which will help you to examine and survey your Wi-Fi network in order to better plan, troubleshoot and deploy it.

 

1. KISMET (free)

 

Kismet logoKismet is a detector, sniffer, and intrusion detection system for 802.11 WLANs. Kismet works by passively collecting packets and detecting standard named networks. Without sending any loggable packets, it detects the presence of both wireless APs and wireless clients, and to associate them with each other. Last update was released in 2013.

Kismet for Windows

Kismet for Mac and Linux

 

2. VISTUMBLER (free)

 

Vistumbler LogoVistumbler is a wireless network scanner written in AutoIT that runs only on Vista, Windows 7, and Windows 8. It shows network’s name, signal strength, kind of encryption, Mac Address, channel, manufacturer. It also graphs the traffic for each network. Last update was released in 2013.

 

Vistumbler for Windows

 

 

3. INSSIDER by MetaGeek

 

inssider metageek logo

InSSIDer is a tool developed by MetaGeek to scan, visualize, and troubleshoot WLANs. It shows what the Wi‑Fi environment looks like, both physically and logically. It identifies signal overlap, channel conflicts, and configuration issues that are degrading the WLAN’s performance.

InSSIDer for Windows

InSSIDer for Mac (via VMware Fusion, Parallels)

InSSIDer for Android

 

4. XIRRUS WI-FI INSPECTOR (free)

 

xirrus logo

The Xirrus Wi-Fi Inspector is a free tool to characterize the integrity and performance of a Wi-Fi network. It detects Rogue APs and provides peak Wi-Fi network performance.

 

 

Xirrus Wi-Fi inspector for Windows

 

5. WIFI EXPLORER

 

wifi explorer logo

WiFi Explorer is a WLANs scanner tool to identify channel conflicts, signal overlapping or configuration problems that may affect the connectivity and performance of a wireless network.

 

 

WiFi Explorer for Mac

 

6. NETSURVEYOR PROFESSIONAL

 

NetSurveyor is an 802.11 network discovery tool that gathers information about nearby wireless access points in real time. It’s useful when installing, testing, and troubleshooting 802.11 adapters and wireless networks. It helps verifying the network is properly configured, trouble-shooting an existing network that is performing poorly, conducting wireless site surveys.

NetSurveyor for Windows

 

7. KISMAC (free)

 

kismac logo

KisMAC is a free, open source wireless stumbling and security tool for Mac OS X. This sniffer/scanner application reveals hidden, cloacked and closed SSIDs; shows logged in clients (with MAC Addresses, IP addresses and signal strengths); can draw area maps of network coverage, thanks to GPS support.

 

 

KisMAC for Mac

 

 

8. NETSPOT (free)

 

netspot logo

NetSpot is a free Mac native tool to conduct network site surveys. It works over any 802.11 network. It helps identify connectivity and wireless interference issues, find sources of excessive noise, resolve Wi-Fi configuration problems.

 

NetSpot for Mac

 

Etwok LLC offers 15% OFF on NetSpot PRO for Tanaza visitors, just place your order via this link to get a better price!

 

“This is the most comprehensive list of network stumblers for Windows, Mac, Linux, Android and iOS”
click to tweet

 

 

Acrylic-WiFi logoAcrylic WiFi is a WiFi scanner that gathers information from 802.11/a/b/g/n/ac networks. It shows: SSIDs/BSSIDs and connected users; signal quality charts for WiFi channels; network authentication and security details for WEP, WPA, WPA2 and Enterprise (802.1X) WLANs.

 

Acrylic WiFi for Windows

 

10. MERAKI WIFI STUMBLER

 

cisco-meraki logo

This is a simple tool to conduct site surveys or track down rogue APs. Results can be sent by e-mail. It shows bridged APs, but not their MAC info. Last update was released in 2010.

 

Meraki WiFi Stumbler for Android

 

11. ISTUMBLER

 

istumbler

iStumbler provides information about nearby Wi-Fi networks, Bluetooth devices, Bonjour services and their Locations. It lists visible wireless networks with complete information, graphically indicates network type and encryption status, identifies signal and noise.

 

 

iStumbler for Mac

 

12. NETSTUMBLER (free)

 

netstumbler-logoNetStumbler is a tool that detects WLANs using 802.11b, 802.11a and 802.11g. No updated version has been developed since 2005. NetStumbler helps detecting networks interference.

NetStumbler for Windows

 

13. WIFI SCANNER

 

wifi scanner accessagility

WiFi Scanner detects access points and clients in ad-hoc mode if the SSID is being broadcasted. Use it for wireless site surveys, wireless discovery, and to connect to WiFi networks. The tool reports signal strength in dBm and shows access point BSSID/MAC addresses. It scans 802.11 a/b/g/n/ac, both 2.4 GHz and 5 GHz bands.

 

 

WiFi Scanner for Mac

 

14. WIRELESSNETVIEW (free)

 

wirelessnetview

WirelessNetView is a small utility that runs in the background, and monitor the activity of wireless networks around you. For each detected network, it displays the following information: SSID, Last Signal Quality, Average Signal Quality, Detection Counter, Authentication Algorithm, Cipher Algorithm, MAC Address, RSSI, Channel Frequency, Channel Number, and more.

 

 

WirelessNetView for Windows

 

15. WIRELESSMON

 

wirelessmonWirelessMon is a software tool that allows users to monitor the status of wireless WiFi adapters and gather information about nearby wireless access points and hotspots. WirelessMon can log the information it collects into a file, while also providing comprehensive graphing of signal level and real time IP and 802.11 WiFi statistics.

 

 

 

iwScanner is a wireless scanner for Linux with an easy to use graphic interface. It gives information about detected wireless networks (AP, MAC, Channel, Encryption, etc) and indentifies signal strenght for every wireless network.

iwScanner for Linux 

 

17. NETSNIFF (free)

 

netsniffNetsniff-ng was initially created by Daniel Borkmann as a network sniffer with support of the Linux kernel packet-mmap interface for network packets. The toolkit currently consists of a network analyzer, packet capturer and replayer, a wire-rate traffic generator, an encrypted multiuser IP tunnel, a Berkeley Packet Filter compiler, networking statistic tools, an autonomous system trace route and more.

 

 

Netsniff for Linux 

 

Unfortunately we didn’t find any stumbler for iOS. This is probably because in 2010 Apple removed several popular Wi-Fi stumblers from the App Store (WiFi-Where, WiFiForum and yFy Network Finder). Apple justify the removal of the apps because they used “a private framework to access wifi information”. This is described in Cult of Mac blog (read more).

 

Cloud superpowers for your Wi-Fi QUICK TOUR VIDEO

Related articles:

 

UniFi cloud management: UniFi Controller or Tanaza?

How to configure radio mode, channel and power level of an AP

How to pick the right channel for your WiFi network

Remotely monitor Wi-Fi Access Points load and memory

 

Whether you are the Sys Admin taking care of a Wi-Fi network of a small hotel with a few Wi-Fi Access Points, or a solution provider with hundreds of Wi-Fi devices deployed in multiple locations, it’s important to know the status of each single AP or Wi-Fi router of your network in any moment, in order to be able to debug the network when needed.

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