Wi-Fi (pronounced:/wa wafa/), also known as "mobile hotspot" in Chinese, is a trademark of the Wi-Fi Alliance manufacturer as a product brand certification, and is a wireless LAN technology based on the IEEE 802.11standard. Wi-Fi is also often used as a synonym for the IEEE 802.11standard, based on the close relationship between the two systems. "Wi-Fi" is often written as "WiFi" or "Wifi", but they are not recognized by the Wi-Fi Alliance.Not every product that matches IEEE 802.11 applies for Wi-Fi Alliance certification, and the relative lack of Wi-Fi certification does not necessarily mean that products are not compatible with Wi-Fi devices.IEEE 802.11 devices have been installed in many products on the market, such as personal computers, game consoles, MP3 players, smartphones, tablets, printers, laptops and other peripheral devices that can access the Internet wirelessly.
The origin of the name
The term Wi-Fi is widely mistaken for Wireless Fidelity, and even the Wi-Fi Alliance itself often uses the term "Wireless Fidelity" in press releases and documents. Wi-Fi also appears in an ITAA paper. But in fact, the word Wi-Fi has no meaning and is not fully written.
Smartphones are part of the growing use of wireless networks in handheld devices. Unlike the Bluetooth technology used in mobile phones earlier, Wi-Fi has a larger coverage range and higher transmission rate, so Wi-Fi mobile phones have become the fashion trend in the mobile communication industry in 2010.
In September 2022, MacRumors reported that a report showed that the first smartphones supporting the next generation Wi-Fi 7 wireless network standard were expected to be available as early as the second half of 2024. [4]
Daily leisure
In 2010, the coverage of wireless networks became more and more extensive in China, with Wi-Fi interfaces in high-end hotels, luxury residential areas, airports and cafes. When traveling and working, you can surf the Internet with handheld devices in these places. Manufacturers only need to set up "hot spots" in airports, stations, coffee shops, libraries and other crowded places, and connect the Internet to these places through high-speed lines.In this way, because the radio waves emitted by the "hot spot" can reach a place with a radius of tens of meters to 100 meters from the access point, users can access the Internet at a high speed as long as they take a notebook computer or PDA or mobile phone or PSP or iPod touch that supports Wi-Fi into the area.
You can also buy a wireless router to set up a LAN at home, and then you can enjoy the wireless Internet.
The difference between wireless network and 3G technology is that 3G has better transmission quality when moving at high speed, but it is enough to use Wi-Fi to surf the Internet when it is static.
The large-scale commercial application of wireless network is a rare successful precedent in the world. The problem focuses on two aspects: one is that large operators do not recognize this model; the other is that they lack an effective business model. However, wireless LAN based on wireless network technology has become increasingly popular, which means that it can be very convenient in the future. Once the public places of Wi-Fi network exist, the problems of interconnection, high charges and roaming of operators are solved, and Wi-Fi will be transformed from a successful technology to a successful business in the future.
People's Daily officially announced that according to the official website of the Wi-Fi Alliance, on September 16, 2019, the Wi-Fi Alliance announced the launch of the Wi-Fi 6 certification program. Compared with the previous generation of Wi-Fi technology standards, Wi-Fi 6 has increased data transmission speed by 40%, can support augmented and virtual reality (AR/VR), expand network capacity, and enjoy high-quality network services even in crowded railway stations.
Passenger train
At 14:20 on November 28, 2014, China's first passenger train with WiFi service, the T809 through train from Guangzhou to Kowloon, Hong Kong, departed from Guangzhou East Railway Station, marking the beginning of the WiFi (wireless network) era for Chinese railways.
After the opening of train WiFi, it can not only watch the high-definition cinema of the local area network inside the carriage, play community games, but also go directly to the external network, brush micro-blog, send e-mail, and connect with the world at a bandwidth speed of 10-50 megabytes.
Public toilets
In 2016, 20 public toilets with free WIFI function will be built in Nanan District of Chongqing.
Composition structure
Generally, the basic equipment for setting up a wireless network is a wireless network card and an AP, so that the network resources can be shared in a wireless mode with the existing wired architecture, and the cost and complexity of setting up the network are far lower than those of the traditional wired network. If it's just a peer-to-peer network for a few computers, you don't need an AP, you just need a wireless network card for each computer. AP is the abbreviation of Access Point, which is generally translated as "wireless access point" or "bridge".It mainly acts as a bridge between wireless station and wired LAN in MAC layer. With an AP, a wireless workstation can quickly and easily connect to the network, just like the Hub of a general wired network. Especially for the use of broadband, Wi-Fi is more advantageous. After the wired broadband network (ADSL, community LAN, etc.) reaches the home, connect to an AP, and then install a wireless network card in the computer.It is enough for an ordinary family to have an AP, and even after the user's neighborhood is authorized, it can access the Internet in a shared way without adding ports.
Hardware device
With the continuous rise and development of wireless networks, wireless network modules are widely used in many fields!
But Wi-Fi module is a high-frequency product after all, unlike ordinary consumer electronics products, there will be some inexplicable phenomena and problems in the production and design, which make some engineers without high-frequency design experience try their best, and practitioners with relevant experience often need to use expensive equipment to assist in the analysis.
For the processing of the wireless network part, there is a design that directly lays out the Wi-Fi part on the PCB motherboard. This design requires courage and technology, because the price of the module itself is not high, and the product corresponding to the motherboard is expensive. When there is a problem with the Wi-Fi part, it is more troublesome to debug and replace it, and it is a pity to scrap it directly; So many designs are willing to adopt the modular Wi-Fi part.In this way, the Wi-Fi part can be directly modularized, which is convenient to handle, and the module can be directly disassembled, which is also very helpful for the design risk and specific wear and tear of the product.
Communication interface: In 2010, USB interface is basically used, and there are a few PCIE and SDIO. The market share of PCIE should be small. The price of all-in-one is expensive, and the practicability is not strong. Many integrated functions will not be used, which is actually a waste
Power supply: Most of them are directly powered by 5V, and some of them are directly powered by 3.3 V by using the power sharing in the motherboard design.
Specification size aspect: This may act according to the concrete design request, smallest has the nano model (may make the nano wireless network card directly); Has may achieve the mini 12 * 12 about (usually is the external antenna way use); Usually is 25 * 12 about design multipoint (basic is the board carries the antenna and the ceramic antenna are many, also has the external antenna attachment).
Form of connection with the motherboard: direct SMT, or plug-in connection through the 2.54 pin header (this is convenient for assembly/maintenance).
The debugging of the software should be combined with the specific scheme, after all, the Wi-Fi part is only a wireless transceiver. Many users are easily confused when consulting. It can be said that the most popular area of Wi-Fi module application in 2013 is the MID market. At the same time, some traditional network application markets have also penetrated, such as some industrial control fields/network broadcasting fields/even some remote control fields are also considered. Basically, the parts that can use the network all want to try wirele
Network Protocol
A Wi-Fi Connection Point Network Member and Structure Station, the most basic component of a network.
Basic Service Set (BSS) is the most basic service unit of the network. The simplest service unit may consist of only two sites. A station may be dynamically Associate into a basic service unit.
Distribution System (DS). The distribution system is used to connect different basic service units. The Medium used by the distribution system is logically distinct from the Medium used by the Bsu, although they may be physically the same medium, such as the same radio frequency band.
Extended Service Set (ESS). It is composed of distribution system and basic service unit. The mix is logical, not physical-different BSSs may be geographically far apart. The dispensing system may also use a variety of techniques.
Portal is also a logical component. It is used to connect wireless local area network with wired local area network or other networks.
There are three types of media, the wireless media used by stations, the media used by distribution systems, and the media used by other LANs integrated with wireless LANs. Physically they may overlap each other.
IEEE 802.11 is only responsible for Addressing on the wireless medium used by the station. The addressing of distribution systems and other local area networks is outside the scope of wireless local area networks.
IEEE 802.11 does not specifically define the distribution system, but only defines the Service that the distribution system should provide. The entire wireless LAN defines nine service
Five services belong to the tasks of the distribution system, namely, Association, Diassociation, Distribution, Integration, and Reassociation.
The four services belong to the tasks of the station, including Authentication, Deauthentication, Privacy, and MAC data delivery.
The Wi-Fi Direct (WFD) project, newly announced by the Wi-Fi Alliance, will allow the Wi-Fi card on your laptop to bypass the access point and connect directly to a wireless printer, digital camera, projector, sensor or plasma screen. As an industry specification, WFD will introduce new protocol implementations in the firmware so that no hardware changes are required.
At the same time, Wi-Fi access points can also become point-to-point connection engines through the 802.11z standard (due to be completed in July 2010), which will provide an extension to direct connection configurations, where a client device requests permission from one access point to connect directly to another nearby client device, but the data does not pass through the access point, and the client is still connected to the access point. A full suite of security and management services is provided by the access point.
Acceleration method
In most cases, the Wi-Fi speed is accelerated by setting a fixed protocol.
The first step is to remove the connected Wi-Fi from the phone, that is, to choose not to save it. (Different versions are displayed differently.)
The second step is to enter 192.168.1.1 or 192.168.0.1 (local) in the browser to enter the control panel of the router and select the setup wizard.
The third step is to change the mode to 11g Only, and the default is 11bgn Mixed.
The fourth step is to restart the router, and then reconnect the phone to Wi-Fi.
(Note: The above method is only compatible with Wi-Fi terminals, which is useless for speed-up, and is the practice of N years ago. Devices can now adapt automatically without this setting.)
Wi-Fi share method
In the absence of Wi-Fi devices, the iPhone and Pad can't use Wi-Fi, which is a very frustrating thing, but you can use the dos command that comes with Win7 system to turn the notebook into a wireless AP transmitter. To provide Internet access to devices such as iPhones and Pads.
00001. 1.
00002. 2. Open the Win7 start menu, find the command prompt option, and run as administrator.
00003.
00004. 3. Enter netsh WLAN set hostednetwork mode = allow ssid = SCC _ Wan key = 1 * 197k51 * on the command line. This string command is to start the virtual wireless network card function of the win7 system. Where "SCC _ Wan" is the SSID, "1 * 197k51 *" is the wireless access password, and the mode parameter is used to specify whether to enable the virtual wireless network card of the system. If the parameter is set to allow, it means that the virtual wireless network card is allowed to be enabled, and disallow means that it is disabled.
00005.
00006. 4. Return to the control panel, double-click the "Network and Sharing Center" icon, click the Change Adapter Settings button, and you will find an additional "Microsoft Virtual Wi-Fi Adapter" "icon, indicating that the virtual wireless AP device has been started successfully.
00007.
00008. 5. To share the Internet network, right click the properties of the adapter that can access the Internet locally in the network neighborhood properties, pop up the properties dialog box of the target network connection, click the "Sharing" tab, and select the options such as "Allow other users to connect through the Internet connection of this computer" in the corresponding setting page. At the same time, select the previously configured wireless network in the list, and then press the OK button.
00009.
00010. 6. Return to the command prompt and type netsh WLAN start hostednetwork to start the virtual wireless service.
00011.
Hernan first used a custom-made instrument to take pictures of Wi-Fi signals to show them. The device continuously scans the Wi-Fi network and then turns the signal strength into a colored led. Hernan ends up with a twisted, curled streak of colored light.
* WMM Power Save: How to extend the battery life by managing the standby time of the wireless network device without affecting its functionality during the transmission of audio and video multimedia through the wireless network can be verified through the test of WMM Power Save
* WPS (Wi-Fi Protected Setup): This is a certification released in early 2007 to allow consumers to set up wireless network devices in a simpler way and ensure a certain degree of security. The current WPS allows the use of Pin Input Config (PIN), Push Button Config (PBC), USB Flash Drive Config (UFD), and Near Field Communication. Contactless Token Config (NFC) to configure the wireless network device.
* ASD (Application Specific Device): This is for wireless network devices with special applications other than wireless network Access Points and Stations, such as DVD players, projectors, printers, etc.
* CWG (Converged Wireless Group): mainly refers to the test program for RF part measurement of Wi-Fi mobile converged devices.
Channel frequency point
2. 2417
3. 2422
4. 2427
5. 2432
6. 2437
7. 2442
8. 2447
9. 2452
10. 2457
11. 2462
12. 2467
13. 24
14. 2484
5. The connection between mobile phone and computer is no longer wired, and wireless can be done.
Commercial operation
Currently, many smartphones and most tablets support Wi-Fi Internet access, which is what most people want to search at any time. It is not only a supplement to wireless broadband access services, but also an important part of innovative operation of operators. From the perspective of global Wi-Fi business development, it is basically impossible to support the development of Wi-Fi business only by providing a single wireless broadband access to achieve profitability.Faced with this situation, there is an urgent need for a new profit model to provide strong support for the development of Wi-Fi and ensure that investment can be rewarded at the same time. Wi-Fi advertising model is obviously a relatively mature and operational model, and the exploration of Wi-Fi advertising model is showing the following new directions.
Direction 1: regional electronic map
The advertising mode based on the regional electronic map of the Wi-Fi login Portal page, that is, based on the different locations of the hotspot, Wi-Fi users will see the electronic map of the current hotspot and its surrounding areas, and operators can use the regional map to continue advertising and marking the businesses around the hotspot.The map of the Wi-Fi portal is marked with a mouse-over phrase. When the user moves the mouse on the regional map, the latest information and links of different businesses will be displayed. When clicking any advertisement, the user will enter the web page interface of the business. The business can update its own business information in the background. The operator is responsible for the maintenance and unified management of the page.For users, this model can not only find the nearest business, restaurant, ATM, gas station, cinema, hospital and other peripheral life information, but also use map navigation, mobile yellow pages and other services. You can also find more in-depth information such as "the latest movie in the cinema" or "the consumption level of the restaurant, how the food tastes".
Benefits to advertisers: Wi-Fi electronic map advertising can combine advertising promotion with advanced and secure wireless network technology, so that business advertising combined with a map with complete information can be close to the nearest potential customers, so that customers who surf the Internet at hot spots can easily find the geographical location of businesses nearby.
Benefits to operators: Take advantage of the time-saving and convenient consumption behavior that customers like to buy nearby, so that a single Wi-Fi hotspot becomes a business circle. The more hotspots, the greater the commercial value of its advertising.
Direction 2: Personalize Portal Page
Personalized advertisements or market research options for merchants are placed on the Wi-Fi account login page and the pop-up page after login. Personalized Portal pages can also be set independently for each hotspot merchant to collect advertisement customization and publishing fees. The main feature of this model is that the operator has the control of the page, and the merchant can use its specific page to publish advertising information.
Benefits to advertisers: Specific personalized advertising pages reach Wi-Fi users directly, allowing users to access the advertising or market research options of businesses at the first time on the Internet, which not only highlights the image of businesses, but also is a good way to conduct market research.
Benefits for operators: By using the unique resources of account login page and the pop-up page after login, you can customize the personalized authentication page of "VLAN + port + IP address" for Portal, and at the same time, you can carry out advertising business on Portal page, built-in service selection and information release, and expand business. Realize the operation of Wi-Fi network.
Direction 3: Geolocation
Advertisers push advertisements by selecting specific regions and hotspots, so that the advertisements of the advertisers can attract potential customers who are most likely to buy their products.At the same time, advertisers can also formulate corresponding special promotions or preferential activities for different geographical areas, so that advertising is more accurate and targeted, and customized information can be pushed to Wi-Fi users for effective advertising.For example, travel service advertisers can push their advertisements to target customers at airport Wi-Fi hotspots, and coffee industry advertisers can push optional advertisements at specific Wi-Fi hotspots such as coffee bars to understand and discover the habits of target customers.
Benefits to advertisers: This model can consciously select the customers who need to advertise through different hot spots or geographical locations according to the wishes and preferences of the merchants, so as to accurately and effectively carry out advertising marketing.
Benefits for operators: Wi-Fi operators can separate different hotspots through IP and VLAN, which can effectively subdivide the customer base, so that the customer base of different hotspots and different scenarios presents different consumption characteristics, thus meeting the requirements of advertisers for accurate delivery of target customer base.
Direction 4: Free Wi-Fi in exchange for advertising
Wi-Fi Internet access is generally achieved by entering account payment, and the operation mode of "free Internet access by watching advertisements" will change this single situation into a "backward payment" operation mode, that is, forward users use Wi-Fi access to the Internet is "zero payment". The so-called "backward payment" refers to the payment by backward advertisers, while users who use wireless networks do not have to pay network service fees.The typical scenario of this model is that before logging on to the Wi-Fi network, Internet users need to watch advertisements on the login page, or click on the market research option button, etc. Users can access the Internet for free as long as they select and submit. The time can be set by the operator, such as 30 minutes. After the user surfs the Internet for 30 minutes, the page will automatically return to a new set of advertising pages. As long as the user goes to see the advertisement or continues to click, he can surf the Internet for another 30 minutes free of charge.
Benefits for advertisers: Because browsing ads or clicking on buttons is the only way for users to surf the Internet for free, the number of views of business advertisements is guaranteed, and the market research of businesses has a broad basis, so advertising on Wi-Fi becomes valuable. For example, set up hotspots in densely populated streets, squares, cafes, bars, restaurants, subways and other areas (in the form of free help for merchants to set up hotspots), and sell advertisements to the outside world. Advertisers can even designate hotspots in a certain area to display advertisements.
Benefits for operators: This model will lower the threshold of Wi-Fi Internet access and increase the number of users. When the number of users increases, the use of Wi-Fi increases, and the value of advertising increases. There should be a certain distinction between this mode and the payment mode, such as paying users will enjoy higher bandwidth than free users, so as not to affect the user experience.
Direction 5: Co-construction of "Attraction" Content
Wi-Fi operators and partners jointly build a "Wi-Fi Zone" content area on the Wi-Fi portal. "Wi-Fi Zone" contains "attractive" content that can attract users. "Attractive" content includes: wonderful movie playing, music downloading, preferential promotion information, activity information, experience information, online printing, etc. Businessmen's advertisements are interspersed in the corresponding content, relying on "attractive" content to be browsed by users.
Benefits to advertisers: Through the "attraction" content, the number of views of advertisements is increased and the effect is enhanced. At the same time, the brand promotion advertisements of some businesses can also be part of the "attraction" content. For example, Starbucks users can receive all kinds of preferential sales information in the store while consuming.
Benefits to operators: Operators cooperate with businesses to establish "Wi-Fi Zone" content, which can attract more users to browse their content online, create excellent content brands, and establish long-term and stable relationships with partners. At the same time, operators can also cooperate with businesses to launch products such as "Wi-Fi Zone" cards, which contain account password information, and users can enjoy the "Wi-Fi Zone" business concessions with the card. This win-win model will attract businesses to invest in advertising in "Wi-Fi Zone.".
It can be seen that with the rapid development of the network, operators can explore new ways of Wi-Fi development by trying to innovate the business model of Wi-Fi; At present, the main business model of Wi-Fi in China is advertising. According to this model, witown, a leading Wi-Fi service provider in China, has developed a set of Wi-Fi marketing system, which transforms the idle Wi-Fi of small and medium-sized enterprises into commercial marketing Wi-Fi. It not only has the routing function of enterprise level,It can also display the functions of enterprise brand zero-cost all-weather advertising through Wi-Fi, which is believed to be a whirlwind in small and medium-sized enterprises in China in the near future.With the acceleration of Wi-Fi network construction, there will be more and more hotspots, and there will be more market space for innovative Wi-Fi applications based on wireless Internet access.
Build the Internet of Things
5G Embedded Wi-Fi Module for Internet of Vehicles
The Internet of Things and other information technologies are the means and tools to build a smart city, and the infrastructure to carry the construction of a smart city. In today's increasingly developed Internet technology, cloud computing, Internet of Things, Internet of Vehicles and other new technologies emerge in endlessly, these new technologies also feed back the Internet, so that the Internet technology itself has achieved unprecedented rapid development.
The emergence of the Internet of Vehicles may be able to change the current situation of the communications industry under the impact of the Internet. If traditional operators seize the opportunities given by the times, it is not impossible for the communications industry to have a second spring, and it will be just around the corner to regain the voice of the industry.
Vehicles are an important part of cities. The total number of motor vehicles in China has reached 233 million, second only to the United States. Based on this huge number of vehicles, the "Internet of Vehicles" came into being. Behind such a considerable number, there are many problems, such as traffic jams, environmental pollution, etc. The Internet of Vehicles is an important driving force for China to build a smart city. The increasing number of customers and the rising demand provide a commercial market for the development of the Internet of Vehicles.
According to US technology media, the unprecedented project is managed by the University of Michigan Transportation Research Center (UMTRI), and about 3000 vehicles will be included in the plan in the next 12 months. Drivers are specially recruited because they often move within the Ann Arbor quarter circle. Each car is connected via a dedicated short-range communication channel, similar to the Wi-Fi network you use at home or in a coffee shop.
All the data will be recorded, so researchers can determine the accuracy of the warning and know which type of warning is best to help drivers stay away from danger. At present, there are no autonomous vehicles, but more sensors are installed in vehicles. Most of the cars were owned by the participants themselves, and the car manufacturer also provided 64 vehicles equipped with embedded communication devices to connect the car's on-board computer network, a customized warning interface from the car manufacturer and multiple cameras.ht
The project is the result of a 10-year effort by the U.S. Department of Transportation, automakers and the University of Michigan Transportation Research Center. The project has invested $25 million, 80% of which is provided by the United States Department of Transportation. Eight major automakers (Ford, General Motors, Honda, Hyundai-Kia, Mercedes-Benz, Nissan, Toyota and Volkswagen) support research through cooperative agreements.
Figures from the National Highway Traffic Safety Administration show that an average of 34000 people die in traffic accidents every year in the United States, requiring about $240 billion to maintain road traffic safety. If the project is promoted on a large scale in the future, it will undoubtedly effectively reduce traffic accidents and avoid casualties.
Connect vehicles to reduce traffic accidents
According to incomplete statistics, more than 1 million people die from traffic accidents in the world every year. Despite the rapid development of science and technology, this worldwide problem is still difficult to solve after decades. Previously, we have also introduced invisible bicycle helmets, Google driverless cars and so on.
Michigan Transportation Research Institute (UMTRI), in conjunction with automobile manufacturers and various institutions, is preparing to launch a cloud platform based on dedicated short-range communication (DSRC), which uses Wi-Fi technology to connect on-board computers and remote traffic safety manag ement platforms to send warning messages before a car is likely to have an accident and remind drivers to pay attention to safety. So as to reduce the occurrence of traffic accidents.
More than 3,000 vehicles will participate in the project in the next year. Staff will equip each vehicle with on-board computers, communication equipment, several sensors and multiple cameras. The on-board computers will transmit real-time signals to the traffic safety management platform when the vehicle is running.
Whenever a dangerous situation occurs, such as speeding or driving in the opposite direction, the safety platform will immediately detect and send a voice or vibration warning through the on-board computer. In addition to providing security warnings, the platform also has other applications, such as setting reminders, remembering to pick up children from school after work, and so on. It also supports developers to develop various applications for it.
Eight major automakers have joined the experiment, including Ford, General Motors, Honda, Hyundai, Mercedes-Benz, Nissan, Toyota and Volkswagen. The Michigan program is currently just a pilot, but it will still cost $2.5 billion. It would cost $24 billion a year if it were rolled out across the United States, but considering that 34000 people die in traffic accidents every year in the United States, life is priceless, and this investment is acceptable.
Covering the whole world
Making every corner of the world wireless may sound like a beautiful idea, but a technology company in the United States plans to make it a reality. The company expects to launch hundreds of mini-satellites into low Earth orbit by June 2015, which will continuously release wireless network signals to the Earth, covering all parts of the world and connecting to wireless networks using any electronic terminal.
On February 26, 2014, an ambitious company in the United States, Media Development Investment Fund, launched a project called "Outernet". The company is in contact with NASA, hoping to get help to carry out signal release tests on the International Space Station, and later need NASA's help to put hundreds of Cube-Sats mini-satellites into designated orbits.According to the assumption, after entering the predetermined orbit, the satellite can receive the network data released from the ground base station, and the satellite needs to parse these data and convert them into wireless networks to release them to the earth.
According to foreign media, American technology entrepreneurs want to cover the world with wireless network signals through a "technology utopia" project called Outernet, according to the webmaster's home. It is reported that the project is to launch hundreds of micro-satellites CubeSats into low Earth orbit, and these satellites are the "birthplace" of free wifi.
In fact, the Outernet project still doesn't provide a complete wireless network. To be precise, the main purpose of the project is to widely disseminate high-quality news and relevant educational information. The communication mode in the Outernet plan tends to be a form of multi-channel wireless planning.
4GHz and can be used by public institutions such as medical institutions.
Because the communication frequency of subway and WiFi is the same, the use of WiFi on the subway may affect the subway communication. However, the communication system and WiFi system of the railway sector use different networks, which are different in frequency band and system system, "there will be no impact between the two systems".
Timely announcement of the progress of "train WiFi"
Synchronous broadcast: WiFi signal does not affect the operation of Chengdu Metro
The relevant person in charge of Chengdu Radio Management Committee said that the use of WiFi on the subway will not affect the operation of the subway.
At the beginning of the planning of Chengdu Metro, the Office of Chengdu Radio Management Committee organized an expert review meeting on the 800MHz digital trunking communication system of Chengdu Metro Line 1 and Line 2, investigated the design of the communication system of Chengdu Metro Company, and confirmed its safety and reliability.
Secondly, before the opening of the subway, the Municipal Radio Monitoring Station of Chengdu was organized to test the electromagnetic environment of all stations of Chengdu Metro Line 1 and Line 2 to ensure the safety of the assigned frequency. At the same time, a regular liaison and communication mechanism has been established, an emergency leading group has been set up, and the e-government emergency network has been connected, so that once the subway has problems in underground operation, the ground can know the situation in time.
WiFi in the air
In August 2023, China Eastern Airlines announced a new breakthrough in the "Wi-Fi in the air" service, which is the first one in China to be open for use below 3000 meters. Passengers can use PED (portable electronic devices) such as mobile phones during the whole flight "from takeoff to landing", enjoy the Internet service in the air, and be "online" at any time.
Precautions
How to ensure the security of mobile banking
Users can establish a connection with the banking system through WAP through a special client program on the mobile phone, and provide financial services such as account inquiry, transfer, payment, consumer payment, etc. This method is called "mobile banking". The first three letters of its website are WAP, which is significantly different from the general way of surfing the Internet.The account information of mobile banking is statically encrypted and bound to the mobile phone. If someone steals your account information, it can not be operated on other mobile phones. After checking with ICBC customer service, they said that in order to facilitate users, they allowed non-designated mobile phones to operate mobile banking accounts, but the amount of funds allowed to operate was very low.
Most importantly, mobile banking also has authentication means. The principle of encryption is very simple. Its purpose is to make unauthorized users unable to use the data even if they obtain it. Authentication is a review measure to ensure that the data is authentic and reliable and that the recipient is authorized, such as whether the data is tampered with and whether the recipient is an authorized user.In terms of the specific technologies and algorithms used, there is no obvious difference between encryption and authentication, but from the functional point of view, they are very different, can not replace each other, and can achieve high security through effective cooperation.
If you enter the correct account number and password, when the operation involves the change of account funds, the mobile phone bank will prompt you to enter a specific electronic password, and the electronic password card is an effective means of authentication. For example, if an electronic password card of ICBC sends information C5H8, you have to enter the corresponding content in the corresponding input box, and the information sent by the bank will be different every time.
Electronic password card of ICBC
Different banks may adopt different authentication methods, such as CCB, which sends mobile phone verification codes by binding mobile phones, but they all play a similar role.
How to ensure the security of personal online banking
Online banking and Alipay's HTTPS page and small padlock logo, click on the small yellow padlock, will pop up the "website logo" box, you can view the certificate.
Moreover, when a computer is used to access personal online banking through HTTPS, there is also the protection of authentication means. The size of the capital limit of the operating account matches the strength of the authentication means. The electronic password card has low authentication strength and can operate less funds, while the U shield has high authentication strength and can operate more funds. Use HTTPS protocol to connect with personal online banking, which is a compulsory measure taken by the bank to ensure security. Information transmitted through non-encrypted protocol will not be accepted by the bank.
Netizens who have used personal online banking will know that the security controls provided by the bank must be installed before use, otherwise the account information column is gray and no information can be entered at all. Mobile phone systems, whether Apple, Android, or Symbian, all do not support this control, simply can not be installed, the account can not be entered naturally, and it is impossible to be stolen.
Some high-level players will install virtual machines on their mobile phones, which may install bank security controls and successfully operate personal online banking. At this time, the mobile phone can be regarded as a simple version of the computer. Naturally, it is also necessary to exchange data with personal online banking through HTTPS security protocol, just like using ordinary computers.
Watch out for phishing sites
Many cases of account theft are actually due to visiting phishing websites. They disguise themselves as regular bank pages or payment pages to cheat you of your account name and password, which does not necessarily need to be achieved through WiFi hotspots, and any way of surfing the Internet may be deceived.However, public WiFi does provide the potential to implant phishing websites, using ARP spoofing to implant a piece of HTML code when users browse websites, so that they automatically jump to phishing websites. From this point of view, public WiFi networks provide users with a convenient fishing environment.
To avoid being fished, we should pay attention to the safety of use. On the one hand, you need to pay more attention to the network address sent by others, because this address may be very close to the domain name address of Taobao and online banking, and the page opened is almost the same as the real program, but in fact you enter a disguised phishing website; On the other hand, try to choose a browser with security authentication function, which can automatically prompt you whether the page you open is safe or not, so as to avoid entering phishing websites.For smartphone users, when downloading client software related to transactions, try to choose official channels to download, and do not install unknown clients.
Conclusion: Whether the bank account is safe or not is not necessarily related to whether the mobile phone is connected to the Internet through free WiFi. It is safe to use mobile banking based on WAP client, and it is also safe to use personal online banking through HTTPS on computers, but do not use personal online banking on mobile phones, and banks do not support this business. When using your computer for personal online banking, please check the HTTPS and the small padlock sign behind the address bar.
Security risk
In June 2014, CCTV's "Dangerous WiFi" program revealed that there are huge security risks in wireless networks, free WiFi hotspots in public places may be fishing traps, and routers at home may be easily broken by malicious attackers. Without knowing it, netizens may face the theft of personal sensitive information, visit phishing websites, and even cause direct economic losses.
Fishing traps
In order to attract customers, many businesses will provide WiFi access services. When customers find WiFi hotspots, they usually ask the waiter for the connection password. Hackers provide a free WiFi access point with a name similar to that of a merchant to attract Internet users.
Once connected to the WiFi hotspot set by the hacker, all the data packets on the Internet will be forwarded through the hacker device, which can be intercepted and analyzed, and some unencrypted communications can be viewed directly.
In addition to disguising a WiFi trap identical to a normal WiFi access point, an attacker can also create an access point with the same name as a normal WiFi access point. Because the wireless router's signal coverage is not stable enough, your phone will automatically connect to the WiFi hotspot created by the attacker. Fall into the trap again without your noticing it.
Active attack
Hackers can use hacker tools to attack the wireless router that is providing services, interfere with the connection, and the network connection of the home router, which is less resistant to attacks, is disconnected, and then connected to the wireless access point set up by hackers.
Attackers will first use various hacker tools to crack the connection password of the home wireless router. If the crack is successful, the hacker will successfully connect your home router and share a LAN.
In addition to enjoying free network bandwidth, attackers will also try to log in to your wireless router management background. Because wireless routers with security risks are quite common on the market, hackers are likely to crack the login password of home routers.
Hijacking risk
In August 2014, Ruben Santamarta, a cyber security researcher, said he had found a way to "hack" satellite communications equipment on civil airliners through aircraft WiFi and in-flight entertainment systems, which could be used by hackers to hijack aircraft.In theory, a hacker could use an aircraft's WiFi signal or in-flight entertainment system to hack into its avionics to disrupt or modify satellite communications, thereby interfering with the aircraft's navigation and safety systems. Therefore, it is theoretically possible to use aircraft WiFi to hijack aircraft.
In 2014, Santa Marta was 32 years old and worked for IOActive, a network security company. He plans to unveil the technical details of his research at the Black Hat conference in Las Vegas on August 7, 2014, in a speech on the security vulnerabilities of satellite communication systems used by aerospace and other industries.
Santa Marta said he discovered the software vulnerabilities in the communication devices through "reverse engineering". The equipment manufacturers involved include Cobham, Harris, Echostar's Hughes Network Systems, Iridium Communications and Japan Wireless.
But Santa Marta said that his "hacking" behavior had only been tested in controlled environments, such as IOActive's laboratory in Madrid, and that it was difficult to replicate in reality. And his decision to go public is to encourage manufacturers to fix what he sees as a safety hazard.
Cobham, Harris, Hughes and Iridium representatives said they had evaluated the Santa Marta study and confirmed some of his findings, but played down the risks. A spokesman for Japan Wireless declined to comment, saying only that information about the security risk would not be made public.
Precautions
First, be cautious about using WiFi hotspots in public places. The WiFi provided by the official organization has a verification mechanism, which can be connected and used after confirmation by the staff. Other public WiFi that can be connected directly and does not require verification or password has a higher risk, and may be a phishing trap behind it, so try not to use it.
Secondly, when using WiFi hotspots in public places, try not to carry out online shopping and online banking operations, so as to avoid the leakage of important personal sensitive information, or even bank transfers by hackers.
Third, develop good WIFI usage habits. The mobile phone will record the used WiFi hotspots, if the WiFi switch is on, the mobile phone will continue to search around, once the hotspot of the same name is encountered, it will automatically connect, there is a risk of phishing. Therefore, when we enter the public area, try not to turn on the WiFi switch, or turn the WiFi to the lock screen and no longer automatically connect, so as to avoid connecting to malicious WiFi without knowing it.
Fourth, the login account and password of the home router management background, do not use the default admin, can be changed to a strong password of letters and numbers; set the WiFi password to choose WPA2 encryption authentication, relatively complex password can greatly increase the difficulty of hackers to crack.
Fifth, security software should be installed on both mobile phones and computers. For hackers commonly used phishing websites and other attack methods, security software can timely intercept reminders. Kingsoft Antivirus is testing the "Routing Management Master" function, which can also effectively prevent home routers from being hijacked by attackers and prevent Internet users from running naked on the Internet.
