What is soft wifi

What is WiFi and How Does it Work?

WiFi is a technology that uses radio waves to provide network connectivity. A connection is established using a wireless adapter to create hotspots — areas in the vicinity of a wireless router that are connected to the network and allow users to access internet services. This article will introduce you to the basics of WiFi so that you may have a better understanding of your Internet access.

What Does WiFi Stand For?

An Introduction to WiFi

Wireless technology is very popular nowadays and you can get connected almost anywhere; at home, at work, in libraries, schools, airports, hotels and even in cafés and restaurants.

Wireless networking is known as WiFi or 802.11 networking as it covers the IEEE 802.11 technologies. The major advantage of WiFi is that it is compatible with almost every operating system, game device, and advanced printer.

How WiFi Works

Like mobile phones, a WiFi network makes use of radio waves to transmit information across a network. The computer should include a wireless adapter that will translate data sent into a radio signal. This same signal will be transmitted, via an antenna, to a decoder known as the router. Once decoded, the data will be sent to the Internet through a wired Ethernet connection.

As the wireless network works as a two-way traffic, the data received from the internet will also pass through the router to be coded into a radio signal that will be received by the computer’s wireless adapter.

WiFi Frequencies

A wireless network will transmit at a frequency level of 2.4 GHz or 5GHz to adapt to the amount of data that is being sent by the user. The 802.11 networking standards will somewhat vary depending mostly on the user’s needs.

The 802.11a will transmit data at a frequency level of 5GHz. The Orthogonal Frequency-Division Multiplexing (OFDM) used enhances reception by dividing the radio signals into smaller signals before reaching the router. You can transmit a maximum of 54 megabits of data per second.

The 802.11b will transmit data at a frequency level of 2.4GHz, which is a relatively slow speed. You can transmit a maximum of 11 megabits of data per second.

The 802.11g will transmit data at 2.4GHz but can transmit a maximum of 54 megabits of data per second as it also uses an OFDM coding.

The more advanced 802.11n can transmit a maximum of 140 megabits of data per second and uses a frequency level of 5GHz.

Here is a comprehensive guide to the latest Wi-Fi 6 technology and a more in depth explanation of the different Wi-Fi types.

What are Hotspots?

The term hotspot is used to define an area where WiFi access is available. It can either be through a closed wireless network at home or in public places such as restaurants or airports.

In order to access hotspots, your computer should include a wireless adapter. but most laptop models in 2020 include a built-in wireless transmitter already. If it doesn’t, you can purchase a wireless adapter that will plug into the PCI slot or USB port. Once installed, your system should automatically detect the WiFi hotspots and request connection. If not, you should use a software to handle this task for you, an example of which you can find here.

Connect To WiFi Via Modem

To start a connection with a wireless router, you must first ensure that it is plugged into the internet connection point. Turn on your external modem before plugging the router into your computer via an Ethernet cable. Then, switch on your wireless router and open your internet browser.

You will be asked to enter in a router IP address. This IP address will vary, depending on the service you use. Users using Belkin should enter http://192.168.2.1.. If you are a Linksys user, enter http://192.168.1.1.

Now fill in your router’s username and password. Set your SSID (wireless capability) as active, and then type in the username and password provided by your ISP and select either WEP or WPA security.

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Soft Access Point Class¶

Section below is ESP8266 specific as Arduino WiFi library documentation does not cover soft access point. The API description is broken down into three short chapters. They cover how to setup soft-AP, manage connection, and obtain information on soft-AP interface configuration.

Table of Contents¶

Set up Network¶

This section describes functions to set up and configure ESP8266 in the soft access point (soft-AP) mode.

softAP¶

Set up a soft access point to establish a Wi-Fi network.

The simplest version (an overload in C++ terms) of this function requires only one parameter and is used to set up an open Wi-Fi network.

To set up pre-shared key protected network, or to configure additional network parameters, use the following overload:

The first parameter of this function is required, remaining four are optional.

Meaning of all parameters is as follows:

ssid — character string containing network SSID (max. 32 characters)

psk — optional character string with a pre-shared key. For WPA2-PSK network it should be minimum 8 characters long and not longer than 64 characters. If not specified, the access point will be open for anybody to connect.

channel — optional parameter to set Wi-Fi channel, from 1 to 13. Default channel = 1.

hidden — optional parameter, if set to true will hide SSID.

max_connection — optional parameter to set max simultaneous connected stations, from 0 to 8. Defaults to 4. Once the max number has been reached, any other station that wants to connect will be forced to wait until an already connected station disconnects.

Function will return true or false depending on result of setting the soft-AP.

The network established by softAP will have default IP address of 192.168.4.1. This address may be changed using softAPConfig (see below).

Even though ESP8266 can operate in soft-AP + station mode, it actually has only one hardware channel. Therefore in soft-AP + station mode, the soft-AP channel will default to the number used by station. For more information how this may affect operation of stations connected to ESP8266’s soft-AP, please check this FAQ entry on Espressif forum.

softAPConfig¶

Configure the soft access point’s network interface.

All parameters are the type of IPAddress and defined as follows:

local_ip — IP address of the soft access point

gateway — gateway IP address

subnet — subnet mask

Function will return true or false depending on result of changing the configuration.

Manage Network¶

Once soft-AP is established you may check the number of stations connected, or shut it down, using the following functions.

softAPgetStationNum¶

Get the count of the stations that are connected to the soft-AP interface.

Note: the maximum number of stations that may be connected to ESP8266 soft-AP is 4 by default. This can be changed from 0 to 8 via the max_connection argument of the softAP method.

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softAPdisconnect¶

Disconnect stations from the network established by the soft-AP.

Function will set currently configured SSID and pre-shared key of the soft-AP to null values. The parameter wifioff is optional. If set to true it will switch the soft-AP mode off.

Function will return true if operation was successful or false if otherwise.

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How WiFi Works

If you’ve been in an airport, coffee shop, library or hotel recently, chances are you’ve been right in the middle of a wireless network. Many people also use wireless networking, also called WiFi or 802.11 networking, to connect their computers at home, and some cities are trying to use the technology to provide free or low-cost Internet access to residents. In the near future, wireless networking may become so widespread that you can access the Internet just about anywhere at any time, without using wires.

WiFi has a lot of advantages. Wireless networks are easy to set up and inexpensive. They’re also unobtrusive — unless you’re on the lookout for a place to watch streaming movies on your tablet, you may not even notice when you’re in a hotspot. In this article, we’ll look at the technology that allows information to travel over the air. We’ll also review what it takes to create a wireless network in your home.

First, let’s go over a few WiFi basics.

A wireless network uses radio waves, just like cell phones, televisions and radios do. In fact, communication across a wireless network is a lot like two-way radio communication. Here’s what happens:

  1. A computer’s wireless adapter translates data into a radio signal and transmits it using an antenna.
  2. A wireless router receives the signal and decodes it. The router sends the information to the Internet using a physical, wired Ethernet connection.

The process also works in reverse, with the router receiving information from the Internet, translating it into a radio signal and sending it to the computer’s wireless adapter.

The radios used for WiFi communication are very similar to the radios used for walkie-talkies, cell phones and other devices. They can transmit and receive radio waves, and they can convert 1s and 0s into radio waves and convert the radio waves back into 1s and 0s. But WiFi radios have a few notable differences from other radios:

  • They transmit at frequencies of 2.4 GHz or 5 GHz. This frequency is considerably higher than the frequencies used for cell phones, walkie-talkies and televisions. The higher frequency allows the signal to carry more data.
  • They use 802.11 networking standards, which come in several flavors:
  • 802.11a transmits at 5 GHz and can move up to 54 megabits of data per second. It also uses orthogonal frequency-division multiplexing (OFDM), a more efficient coding technique that splits that radio signal into several sub-signals before they reach a receiver. This greatly reduces interference.
  • 802.11b is the slowest and least expensive standard. For a while, its cost made it popular, but now it’s becoming less common as faster standards become less expensive. 802.11b transmits in the 2.4 GHz frequency band of the radio spectrum. It can handle up to 11 megabits of data per second, and it uses complementary code keying (CCK) modulation to improve speeds.
  • 802.11g transmits at 2.4 GHz like 802.11b, but it’s a lot faster — it can handle up to 54 megabits of data per second. 802.11g is faster because it uses the same OFDM coding as 802.11a.
  • 802.11n is the most widely available of the standards and is backward compatible with a, b and g. It significantly improved speed and range over its predecessors. For instance, although 802.11g theoretically moves 54 megabits of data per second, it only achieves real-world speeds of about 24 megabits of data per second because of network congestion. 802.11n, however, reportedly can achieve speeds as high as 140 megabits per second. 802.11n can transmit up to four streams of data, each at a maximum of 150 megabits per second, but most routers only allow for two or three streams.
  • 802.11ac is the newest standard as of early 2013. It has yet to be widely adopted, and is still in draft form at the Institute of Electrical and Electronics Engineers (IEEE), but devices that support it are already on the market. 802.11ac is backward compatible with 802.11n (and therefore the others, too), with n on the 2.4 GHz band and ac on the 5 GHz band. It is less prone to interference and far faster than its predecessors, pushing a maximum of 450 megabits per second on a single stream, although real-world speeds may be lower. Like 802.11n, it allows for transmission on multiple spatial streams — up to eight, optionally. It is sometimes called 5G because of its frequency band, sometimes Gigabit WiFi because of its potential to exceed a gigabit per second on multiple streams and sometimes Very High Throughput (VHT) for the same reason.
  • Other 802.11 standards focus on specific applications of wireless networks, like wide area networks (WANs) inside vehicles or technology that lets you move from one wireless network to another seamlessly.
  • WiFi radios can transmit on any of three frequency bands. Or, they can "frequency hop" rapidly between the different bands. Frequency hopping helps reduce interference and lets multiple devices use the same wireless connection simultaneously.

As long as they all have wireless adapters, several devices can use one router to connect to the Internet. This connection is convenient, virtually invisible and fairly reliable; however, if the router fails or if too many people try to use high-bandwidth applications at the same time, users can experience interference or lose their connections. Although newer, faster standards like 802.11ac could help with that.

Next, we’ll look at how to connect to the Internet from a WiFi hotspot.

You may be wondering why people refer to WiFi as 802.11 networking. The 802.11 designation comes from the IEEE. The IEEE sets standards for a range of technological protocols, and it uses a numbering system to classify these standards.

WiMax, also known as 802.16, looks to combine the benefits of broadband and wireless. WiMax will provide high-speed wireless Internet over very long distances and will most likely provide access to large areas such as cities.

A WiFi hotspot is simply an area with an accessible wireless network. The term is most often used to refer to wireless networks in public areas like airports and coffee shops. Some are free and some require fees for use, but in either case they can be handy when you are on the go. You can even create your own mobile hotspot using a cell phone or an external device that can connect to a cellular network. And you can always set up a WiFi network at home.

If you want to take advantage of public WiFi hotspots or your own home-based network, the first thing you’ll need to do is make sure your computer has the right gear. Most new laptops and many new desktop computers come with built-in wireless transmitters, and just about all mobile devices are WiFi enabled. If your computer isn’t already equipped, you can buy a wireless adapter that plugs into the PC card slot or USB port. Desktop computers can use USB adapters, or you can buy an adapter that plugs into the PCI slot inside the computer’s case. Many of these adapters can use more than one 802.11 standard.

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Once you’ve installed a wireless adapter and the drivers that allow it to operate, your computer should be able to automatically discover existing networks. This means that when you turn your computer on in a WiFi hotspot, the computer will inform you that the network exists and ask whether you want to connect to it. If you have an older computer, you may need to use a software program to detect and connect to a wireless network.

Being able to connect to the Internet in public hotspots is extremely convenient. Wireless home networks are convenient as well. They allow you to easily connect multiple computers and to move them from place to place without disconnecting and reconnecting wires. In the next section, we’ll look at how to create a wireless network in your home.

Building a Wireless Network

If you already have several computers networked in your home, you can create a wireless network with a wireless access point. If you have several computers that are not networked, or if you want to replace your Ethernet network, you’ll need a wireless router. This is a single unit that contains:

  1. A port to connect to your cable or DSL modem
  2. A router
  3. An Ethernet hub
  4. A firewall
  5. A wireless access point

A wireless router allows you to use wireless signals or Ethernet cables to connect your computers and mobile devices to one another, to a printer and to the Internet. Most routers provide coverage for about 100 feet (30.5 meters) in all directions, although walls and doors can block the signal. If your home is very large, you can buy inexpensive range extenders or repeaters to increase your router’s range.

As with wireless adapters, many routers can use more than one 802.11 standard. Normally, 802.11b routers are slightly less expensive than others, but because the standard is older, they’re also slower than 802.11a, 802.11g, 802.11n and 802.11ac routers. 802.11n routers are the most common.

Once you plug in your router, it should start working at its default settings. Most routers let you use a Web interface to change your settings. You can select:

  • The name of the network, known as its service set identifier (SSID) — The default setting is usually the manufacturer’s name.
  • The channel that the router uses — Most routers use channel 6 by default. If you live in an apartment and your neighbors are also using channel 6, you may experience interference. Switching to a different channel should eliminate the problem.
  • Your router’s security options — Many routers use a standard, publicly available sign-on, so it’s a good idea to set your own username and password.

Security is an important part of a home wireless network, as well as public WiFi hotspots. If you set your router to create an open hotspot, anyone who has a wireless card will be able to use your signal. Most people would rather keep strangers out of their network, though. Doing so requires you to take a few security precautions.

It’s also important to make sure your security precautions are current. The Wired Equivalency Privacy (WEP) security measure was once the standard for WAN security. The idea behind WEP was to create a wireless security platform that would make any wireless network as secure as a traditional wired network. But hackers discovered vulnerabilities in the WEP approach, and today it’s easy to find applications and programs that can compromise a WAN running WEP security. It was succeeded by the first version of WiFi Protected Access (WPA), which uses Temporal Key Integrity Protocol (TKIP) encryption and is a step up from WEP, but is also no longer considered secure.

To keep your network private, you can use one or both of the following methods:

  • WiFi Protected Access version 2 (WPA2) is the successor to WEP and WPA, and is now the recommended security standard for WiFi networks. It uses either TKIP or Advanced Encryption Standard (AES) encryption, depending upon what you choose at setup. AES is considered the most secure. As with WEP and the initial WPA, WPA2 security involves signing on with a password. Public hotspots are either open or use any of the available security protocols, including WEP, so use caution when connecting away from home. WiFi Protected Setup (WPS), a feature that ties a hard-coded PIN to the router and makes setup easier, apparently creates a vulnerability that can be exploited by hackers, so you may want to turn off WPS if possible, or look into routers that do not have the feature.
  • Media Access Control (MAC) address filtering is a little different from WEP, WPA or WPA2. It doesn’t use a password to authenticate users — it uses a computer’s physical hardware. Each computer has its own unique MAC address. MAC address filtering allows only machines with specific MAC addresses to access the network. You must specify which addresses are allowed when you set up your router. If you buy a new computer or if visitors to your home want to use your network, you’ll need to add the new machines’ MAC addresses to the list of approved addresses. The system isn’t foolproof. A clever hacker can spoof a MAC address — that is, copy a known MAC address to fool the network that the computer he or she is using belongs on the network.

You can also change other router settings to improve security. For instance, you can set it to block WAN requests to keep the router from responding to IP requests from remote users, set a limit to the number of devices that can connect to your router and even disable remote administration so that only computers plugged directly into your router can change your network settings. You should also change the Service Set Identifier (SSID), which is your network name, to something other than the default so that hackers can’t immediately tell what router you are using. And selecting a strong password never hurts.

Wireless networks are easy and inexpensive to set up, and most routers’ Web interfaces are virtually self-explanatory. For more information on setting up and using a wireless network, check out the links on the next page.

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What Is Wi-Fi?

Wi-Fi is a wireless networking technology that allows devices such as computers (laptops and desktops), mobile devices (smart phones and wearables), and other equipment (printers and video cameras) to interface with the Internet. It allows these devices—and many more—to exchange information with one another, creating a network.

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Internet connectivity occurs through a wireless router. When you access Wi-Fi, you are connecting to a wireless router that allows your Wi-Fi-compatible devices to interface with the Internet.

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A renewed focus on business resilience

Our world is facing an acceleration in the frequency, diversity, and impact of disruptions. Planning your network to help your organization respond to the unexpected is now more important than ever.

What does Wi-Fi mean?

Wi-Fi is not an acronym; it is a brand name created by a marketing firm that’s meant to serve as an interoperability seal for marketing efforts.

How does Wi-Fi work?

On the technical side, the IEEE 802.11 standard defines the protocols that enable communications with current Wi-Fi-enabled wireless devices, including wireless routers and wireless access points. Wireless access points support different IEEE standards.

Each standard is an amendment that was ratified over time. The standards operate on varying frequencies, deliver different bandwidth, and support different numbers of channels.

What is a wireless access point?

A wireless access point (AP) allows wireless devices to connect to the wireless network. Having a Cisco wireless network makes it easy to bring new devices online and provides flexible support to mobile workers.

What a wireless access point does for your network is similar to what an amplifier does for your home stereo. An access point takes the bandwidth coming from a router and stretches it so that many devices can go on the network from farther distances away. But a wireless access point does more than simply extend Wi-Fi. It can also give useful data about the devices on the network, provide proactive security, and serve many other practical purposes.

What is a wireless router?

Wireless routers are commonly found in homes. They’re the hardware devices that Internet service providers use to connect you to their cable or xDSL Internet network.

A wireless router is sometimes referred to as a wireless local area network (WLAN) device. A wireless network is also called a Wi-Fi network.

A wireless router combines the networking functions of a wireless access point and a router. Read more about wireless routers.

What is a desktop Wi-Fi router?

The most common way for users to connect to the Internet wirelessly is with a desktop wireless (Wi-Fi) router. These routers look like small boxes with multiple short antennas to help broadcast the signal throughout a home or workplace. The farther a user is from the base Wi-Fi router, the weaker the signal. So multiple wireless routers, called range extenders, usually are placed throughout the workspace. Wi-Fi range extenders, placed in an array, boost or extend Internet coverage.

What is a mobile hotspot?

A mobile hotspot is a common feature on smartphones with both tethered and untethered connections. When you turn on your phone’s mobile hotspot, you share your wireless network connection with other devices that can then access the Internet.

What is portable Wi-Fi hotspot?

A portable Wi-Fi hotspot is a mobile hotspot obtained through a cell phone carrier. It’s a small device that uses cellular towers that broadcast high-speed 3G or 4G broadband signals. Multiple devices, like iPads and laptops, can then connect wirelessly to the device, which in turn seamlessly connects to the Internet where ever you travel. Similar to a cell phone, the portable hotspot’s monthly cost is based on the data usage plan you select. A portable Wi-Fi hotspot is a more reliable way to access the Internet than searching for static public Wi-Fi hotspots.

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Soft Access Point Class¶

Section below is ESP8266 specific as Arduino WiFi library documentation does not cover soft access point. The API description is broken down into three short chapters. They cover how to setup soft-AP, manage connection, and obtain information on soft-AP interface configuration.

Table of Contents¶

Set up Network¶

This section describes functions to set up and configure ESP8266 in the soft access point (soft-AP) mode.

softAP¶

Set up a soft access point to establish a Wi-Fi network.

The simplest version (an overload in C++ terms) of this function requires only one parameter and is used to set up an open Wi-Fi network.

To set up pre-shared key protected network, or to configure additional network parameters, use the following overload:

The first parameter of this function is required, remaining four are optional.

Meaning of all parameters is as follows:

ssid — character string containing network SSID (max. 32 characters)

psk — optional character string with a pre-shared key. For WPA2-PSK network it should be minimum 8 characters long and not longer than 64 characters. If not specified, the access point will be open for anybody to connect.

channel — optional parameter to set Wi-Fi channel, from 1 to 13. Default channel = 1.

hidden — optional parameter, if set to true will hide SSID.

max_connection — optional parameter to set max simultaneous connected stations, from 0 to 8. Defaults to 4. Once the max number has been reached, any other station that wants to connect will be forced to wait until an already connected station disconnects.

Function will return true or false depending on result of setting the soft-AP.

The network established by softAP will have default IP address of 192.168.4.1. This address may be changed using softAPConfig (see below).

Even though ESP8266 can operate in soft-AP + station mode, it actually has only one hardware channel. Therefore in soft-AP + station mode, the soft-AP channel will default to the number used by station. For more information how this may affect operation of stations connected to ESP8266’s soft-AP, please check this FAQ entry on Espressif forum.

softAPConfig¶

Configure the soft access point’s network interface.

All parameters are the type of IPAddress and defined as follows:

local_ip — IP address of the soft access point

gateway — gateway IP address

subnet — subnet mask

Function will return true or false depending on result of changing the configuration.

Manage Network¶

Once soft-AP is established you may check the number of stations connected, or shut it down, using the following functions.

softAPgetStationNum¶

Get the count of the stations that are connected to the soft-AP interface.

Note: the maximum number of stations that may be connected to ESP8266 soft-AP is 4 by default. This can be changed from 0 to 8 via the max_connection argument of the softAP method.

softAPdisconnect¶

Disconnect stations from the network established by the soft-AP.

Function will set currently configured SSID and pre-shared key of the soft-AP to null values. The parameter wifioff is optional. If set to true it will switch the soft-AP mode off.

Function will return true if operation was successful or false if otherwise.

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