How can you calculate WiFi bandwidth needs when designing the network? What specific considerations are involved?
What is bandwidth in networking?
The basic unit of this language, the byte, is composed of 8 bits. The bandwidth determines, therefore, the number of bytes that can be transmitted on the connection. The unit of measurement is the bits per second (bps). For example, a low definition video lasting 15 seconds, weighing 1 Megabyte, can be downloaded from an Internet site on your computer in 3-5 minutes if the connection is made via modem (56 kbps) or ISDN line (from 64 to 128 kbps). The same action takes a few seconds instead if the connection is broadband, like the one with the optical fibers (over 1000 Gbps).
Network bandwidth is the capacity of a network communications link to transmit the maximum volume of data from one point to another over a computer network or Internet connection in a given amount of time, usually one second. Bandwidth has the same meaning of capacity, and defines the data transfer rate.
Bandwidth, though, is not a measure of network speed.
As a matter of fact, the words “bandwidth” and “speed” are often misused as synonymous. The explanation of this misunderstanding can be, in part, due to their use in advertisements by ISPs that refer to speeds when they mean bandwidth. Indeed, speed refers to the rate at which data can be sent, while the definition of bandwidth is the capacity for that speed.
Why is it so important to calculate network bandwidth requirements before deploying a network?
Consider that in any kind of deployment location, there are bandwidth limits. This means that there is a constraint to space for the data to flow. Therefore, multiple devices in a single area must share the bandwidth. Some devices request much more bandwidth than others. Greater bandwidth is absolutely necessary if proper speed must be maintained on different devices.
When do you need to calculate bandwidth?
Before you start designing your WiFi network, you should follow some steps to achieve your bandwidth goal.
1. Estimate how many devices will be connected to your WiFi network simultaneously
Each computer or device added to your network will degrade the bandwidth available to the other devices using the same connection. All those devices share the same wireless network and the same Internet connection from your broadband service provider. In this case, the congestion isn’t necessarily with the wireless connections. Still, it is with the amount of traffic or bandwidth that can pass through the Internet router to your broadband service provider.
If you want to estimate how many concurrent devices will be connected, consider, for example, a hotel with 18 rooms for 2 people each. The hotel has 36 guests if it is fully-booked. If each guest has 1.2 devices, you have around 43 devices in total. We can assume that only 20 of 43 can be connected or generate significant traffic at the same time.
2. Calculate the application bandwidth requirement
To implement a high-performance WLAN, network designers must consider external variables, such as the applications’ requirements in bandwidth and throughput networks.
Tanaza offers a useful way to calculate the bandwidth requirement of a network. We have created the tool “Access Point Selector” to suggest the ideal access point per location and application type. However, it’s also helpful to estimate the required bandwidth per-user connection. You can try it here.
In the image below, you can check the bandwidth needed and the throughput required for the mainstream applications, such as messaging, e-mails, social media, video calls, VoIP calls, web browsing, file sharing, and video streaming.
Alternatively, you can measure the bandwidth requirements by usage. The chart below compares minimum download speed (Mbps) needs for light, moderate, and high household use with one, two, three, or four devices at a time (such as a laptop, tablet, or game console).
If you are using our Access Point Selector tool, in a hotel with 35 concurrent users employing chatting/messenger services, e-mail, social media, web browsing, and video streaming, you will have, as a result, an estimated bandwidth per user of 3.33 Mbit/s. This means that the hotel would need at minimum: Location bandwidth – 117 Mbit/s.
3. Calculate network bandwidth requirements
Furthermore, bandwidth connections can be symmetrical when the data capacity is the same in uploading or downloading data, and asymmetrical when download and upload capacity are not the same. In asymmetrical connections, upload capacity is usually smaller than the download capacity.
In addition to testing, you have to calculate how much bandwidth is needed to run all your networks’ applications. To understand how much capacity you need, you must calculate the maximum number of users who might be using the network connection simultaneously and multiply that number times the bandwidth capacity required by each application.
To calculate the bandwidth need required you can use the following formula:
(Application Throughput) x (Number of concurrent Users) = Aggregate Application Throughput
(3.33 Mbps) x 35 concurrent users = 117 Mbps
Note: the result you get here might exceed the bandwidth that the internet service providers offer.
If you are deploying wireless networks, read also WiFi network design – What to take into consideration when designing WLANs, there are many factors to consider to plan out your network deployments thoroughly.
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How many access points do you need for your WiFi hotspot
When deploying a Wi-Fi infrastructure in public locations, one of the key element to ensure a good user experience is the number and the type of access points to use.
Indeed, if the number of access points is too low compared to the number of Wi-Fi users, then problems of internet speed might occur because of the overuse of the wireless devices and the bandwidth overload. Usually, the maximum number of concurrent users is written on the manufacturer spreadsheet, but in practice it can vary according to the use of your network and the internet services you want to offer to your Wi-Fi users.
By using the Tanaza Access Point Selector, you can select the type of location and its size to estimate the maximum number of concurrent users. The number of concurrent users is the number of Wi-Fi users currently connected to the Wi-Fi network. It is calculated according to the type of location, its size, and the average time that a user spends on the internet. Count for example ten concurrent users for a large Café, or 140 for a large hotel.
Last but not least, select the characteristics of the access point such as the installation type, the radiation shape, the vendor and the main technology aspects (indoor, outdoor, AC, dual radio…). The Tanaza Access Point Selector will give you an estimation of the required units number, and the different models that fit the best your project.
/!\ Remember that the Tanaza Access Point Selector estimates the required bandwidth based on documentation and our experience on-site with our customers.
WPA3: what are the main changes to the wireless security standard
After the KRACK attack and the discovery of WPA2 security problem that was putting at hijack risk all WPA2-compatible device like routers, computers and smartphones, Wi-Fi Alliance has announced a new security protocol: WPA3. WPA3 is a substitute for WPA2 (the wireless security standard since 2004) and should be landed later in 2018.
Four new capabilities will be launched in 2018 as part of the Wi-Fi certified WPA3. These features, available for personal and Wi-Fi networks enterprises, consist in delivering more robust protection regarding user’s password to access a Wi-Fi network and simplifying the security configuration for devices with a limited, or no display interface.
For example, a WPA3 key improvement aims to block “dictionary attacks”, or when a hacker tries to gain unauthorised access to a computer system by using a large set of words to generate potential passwords.
The new security protocol should prevent hackers from guessing a list of potential passwords to access a Wi-Fi network. Moreover, the hacker will be blocked after too many failed password thanks to its new handshake system ( WPA2 currently uses a four-way handshake).
Another interesting change touches on the open Wi-Fi networks. Open Wi-Fi networks are all networks in public spaces like café, airport, parks… that are not encrypted and so risky for the user whose data could be intercepted by a hacker.
WPA3 will use individualized data encryption that muddles the connection between each device on a network and the router. By doing so, WPA3 prevents hackers from stealing data or modifying websites.
Obviously, building a new wireless security standard takes time, and WPA3 won’t substitute WPA2 before few months, but Wi-Fi Alliance underlined the necessity of updating Wi-Fi security in a modern society where the Wi-Fi demand is increasing.
How to choose the best access point for your restaurant’s WiFi network (part 1)
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.
Security breach in WPA2 protocol: what is the KRACK attack?
“KRACK Wi-Fi attack threatens all networks”, “KRACK Wi-Fi flaw, the big issue for Wi-Fi network”… the internet has been in shambles for ten days due to the flaw discovery on the Wi-Fi network security process.
What is the KRACK issue?
KRACK stands for Key Reinstallation AttaCK and it designates the issue occurring when the third step of a four-way authentication process, performs in the wrong way.
To be clear, during the third step of the authentication process (when a device tries to connect to a protected Wi-Fi network), the encryption key can be sent multiple times to get access to the protected Wi-Fi network. Security issues occur when a hacker can collect this information and replay the transmission to break the Wi-Fi security encryption key.
What happens when the Wi-Fi encryption key is broken?
If a hacker gets the encryption key, they will be able to “sniff” your data and steal your sensitive information such as credit card details, emails, pictures, passwords and so on. The risk is the same as using a non-protected Wi-Fi network; users data is potentially accessible to all.
Moreover, the United-States Computer Emergency Readiness Team declared about KRACK issues that “the impact of exploiting these vulnerabilities includes decryption, packet replay, TCP connection hijacking, HTTP content injection, and others”.
Which devices are vulnerable?
The KRACK attack is not an issue for the device itself, but the information it contains. All data sent on a Wi-Fi network without encryption key is as vulnerable as it when the user visits websites that are not HTTPS. You need to update your smartphone, tablet, router and computer with the latest security release to reduce the risk of data theft. Nevertheless, researchers said Android devices were more likely to be at risk rather than other mobile phones, same for Linux runners, considered as the most vulnerable devices.
Why are Tanaza users not concerned by this KRACK issue?
To prevent KRACK attacks in any Tanaza network, Tanaza introduced the fix in its latest firmware release. To avoid any risk, both the firmware and the customer device have to contain the fix for this attack.
This specific attack is against the 4-way handshake and it’s explicitly intended to exploit customers devices rather than access points. By using the Man-in-the-Middle attack (or MitM), hackers try to gather sensible data by misleading the device for the connection authentication and the user for the web surfing security (e.g. preventing websites from using HTTPS encryption and collecting any data such as usernames and passwords during any login process).
In a few words, if your access points runs on the latest Tanaza firmware and your devices are updated, you are protected from this KRACK issue.
4 reasons why 5G cellular won’t be a threat to Wi-Fi
In this scenario, is there a chance that the new 5G cellular network will eventually replace Wi-Fi?
We answered this question providing the main 4 reasons as to why the 5th generation wireless system (5G) and next generation Wi-Fi will probably coexist without representing a threat one for the other. In doing so, we relied on information collected by different sources, including: The 5G vs WiFi False Debate by Adlane Fellah, Shared Spectrum: Enabling 5G Mobile Broadband by Alex Marcham and 5G CELLULAR: WHY WI-FI NOT JUST SURVIVES, BUT PROSPERS by Craig Mathias.
1. Mobile users will likely continue to favour Wi-Fi over mobile connectivity
Currently, many mobile users prefer using Wi-Fi networks instead of 4G cellular ones. In particular, in developing countries where mobile connectivity is lacking and in developed mobile markets where mobile data is overpriced and limited, Wi-Fi is a valuable choice among smartphone users. Accordingly, as 5G is going to be the evolution of the current 4G cellular network, it is likely that many users will still favor Wi-Fi over 5G.
2. Wi-Fi will still be an affordable alternative to 5G
According to Cisco, by the end of 2021 data traffic on mobile networks per month will reach 49 EB (exabytes), in line with the development registered between 2011 and 2015. Consequently, the new 5G cellular, other than on the licensed spectrum, will also operate on the more affordable unlicensed and shared spectrum. This spectrum, in fact, currently enables technologies like Wi-Fi to foster connectivity and facilitate innovation while also carrying the growing number of data traffic expected in upcoming years.
To handle the large of amount of data traffic coming their way, network operators will opt to work with all technologies operating on the unlicensed spectrum, as opposed to solely relying on private licensed ones. This scenario might make it possible for customers in the Wi-Fi market – other than mobile network operators – to opt for 5G over Wi-Fi in the unlicensed and shared spectrum. Nevertheless, despite 5G’s well-performing connection, it is likely that it will be offered at a high price. This will continue to make Wi-Fi a valuable and affordable alternative choice for many customers due to the fact that lot of effort and money is required to enable the 5G connection to work with both the licensed and the unlicensed spectrum based on different protocols.
3. Wi-Fi already masters dense deployments
Given the expected extensive data traffic in the upcoming years, 5G will also rely more and more on small cells, which are known to be very effective to improve capacity, coverage and data range in congested areas. From this point of view, as opposed to 5G, Wi-Fi already has a big advantage, as it masters crowded deployments. Compared to the other wireless access technologies, Wi-Fi has the right requirements to handle the growing demand for connectivity by being able to increase the capacity of mobile networks and carrying large amounts of data traffic.
4. The Wi-Fi market is expected to increase
In the past few years, WI-Fi along with other cellular networks have developed extensively and its growth predictions are far optimistic. In fact, the global hotspot predictions for 2015-2020 made by Cisco’s VNI Mobile, show that Wi-Fi traffic, both from mobile and Wi-Fi-only devices, will account for 53% of total IP traffic by 2019.