Abstract
In recent years, wireless local area network technology has become more and more mature, and its application range has become wider and wider. Wireless local area networks have entered thousands of households and have changed people's lifestyles and life concepts in many ways. This article briefly introduces wireless LAN networking methods, current general security technologies and existing security risks; through WiFi password cracking experiments, it is intended to help everyone understand wireless LANs and use current technologies to protect their wireless LAN security.
Keywords: wireless local area network, network security technology, IEEE802.11 standards, WPA/WPA2, password cracking
Abstract
in recent years wireless local area network technology has become more mature, more and more extensive scope of application. Wireless LANs have entered thousands of households, and in many aspects of changing people's life style and concept of life. This paper introduces a wireless LAN networking mode, there are security risks and the current security technology general; through the WiFi password cracking experiment, is intended to help you understand the wireless LAN and the rational use of current technology to protect the safety and security of wireless local area network of their own.
Keywords: wireless local area network, network security technology, IEEE802.11 standard, WPA/WPA2, password cracking
Contents
Introduction 1
Chapter 1: Basic Introduction of
Wireless Local Area Network 1 1.1 Introduction of Wireless Local Area Network 1 1.
2 Main Standards of
Wireless Local Area Network 2 1. 3 Wireless Local Area Network Structure 4
1. Peer-to-Peer Method 4
2. Access Method: 5
3 .Relay mode: 5
Chapter 2: Wireless LAN Security Technology 6
2.1 Service Area Identifier (SSID) Matching 6
2.2 MAC Physical Address Filtering 6
2.3 WEP Wired Equivalent Privacy 7
2.4 AP Isolation 7
2.5 802.1X protocol 7
2.6 WPA (Wi-Fi Protected Access) 8
2.7 Virtual Private Network (***) 8
Chapter 3: Wireless LAN Security Issues 9
3.1 Physical Security 9
3.2 Roamer 9
3.3 Fraudulent access point 9
3.4 Double-sided demon*** 9
3.5 Hijacking and monitoring of wireless communication 10
Chapter 4: Introduction to common WiFi password cracking 10
4.1 Intercepting data packets Run dictionary cracking method 10
(1) Prepare software and hardware tools 10
(2) Cracking process 10
(3) Intercepted data packets and run dictionary cracking method analysis 14
4.2 Pin code exhaustive cracking method 14
(1) Cracking principle 14
(2) Cracking process 15
(3) PIN code exhaustive cracking method analysis 17
4.3 FeedingBottle Cracking Method 17
Chapter 5: Basic Security Configuration of WLAN 20
- 1 Physical protection 20
5.2 Upgrade hardware equipment 20
5.3 Modify SSID 21 - 4 Turn on behavior control 21
5.5 Replace WEP with WPA/WPA2 22
5.6 Modify the default management address and management account 23
References: 25
Introduction
Wireless Local Area Networks (Wireless Local Area Networks; abbreviated as: WLAN) is a very convenient data transmission system. It uses radio frequency (RF) technology to replace the old-fashioned twisted pair copper wire in the local area network, making the wireless local area network Network can use a simple access structure to allow users to achieve the ideal state of "information portable and convenient to travel the world". The wireless local area network (WLAN) industry is currently one of the fastest growing industries in the entire data communications field. Because of its flexibility, mobility and lower investment cost, the wireless LAN solution, as a supplement and expansion of the traditional wired LAN, has won home network users, small and medium office users, a large number of enterprise users and telecom operators However, because wireless local area networks use public frequency electromagnetic waves as the carrier, it is less easy to guard against unauthorized access and eavesdropping, making it more difficult to guarantee its security and facing serious security threats. We need wireless networks The convenience and efficiency brought by it require the wireless network to bring us reliable information security.
Chapter 1: Basic Introduction to Wireless Local Area
Network 1.1 Introduction to
Wireless Local Area Network Wireless Local Area Networks (Wireless Local Area Networks, WLAN). It uses radio frequency (RF) technology to replace the old-fashioned twisted pair copper wire in the local area network, so that the wireless local area network can use a simple access structure to let users feel ubiquitous information. Wireless network has the incomparable advantages of traditional wired network: (1) Flexibility, not limited by cables, it is more convenient to add and configure workstations. (2) Low cost, the wireless network does not require a lot of engineering wiring, and at the same time saves the cost of line maintenance. (3) Mobility, less restricted by space and region, you can surf the Internet anytime and anywhere in the coverage area. (4) Easy to install. Compared with wired, wireless network is easier to set up, configure, and maintain. (5) More beautiful, traditional wired network affects the beautiful in many cases, but wireless network does not have this problem. At the same time, wireless networks also have many defects: (1) The speed of wireless networks is not very stable, and there is still a big gap compared with wired networks. (2) Security is also a major issue. The wireless network is transmitted through specific radio waves. Therefore, within the effective range of the transmitting frequency, anyone with a suitable receiving device can capture the signal of this frequency. Data can be intercepted and inserted within the scope. Therefore, there are major security threats in the wireless network communication process.
1.2 The main standard of wireless local area network The
IEEE802 committee established the IEEE802.11 working group in 1990, dedicated to wireless local area network (WLAN), which has the right to develop MAC protocols and physical media specifications. Since the release of IEEE802.11 in 1997, a total of 14 standards have been released, including 802.11b, 802.11a, 802.11g, 802.11c, 802.11d, 802.11e, and 802.11n. Each standard has its own focus, and some of them It is still expanding.
IEEE802.11 is also called wireless fidelity-wifi, which defines 2 RF transmission methods and 1 infrared transmission method. In this standard, the RF transmission standard adopts frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS direct sequence spread spectrum) technology. Among them, FHSS uses 2 to 4 level Gaussian frequency shift keying (GFSK, Gaussian frequency shift keying) modulation technology, supports 1Mb/s transmission rate, a total of 22 groups of frequency hopping patterns, including 79 channels; DSSS uses binary phase shift keying (BPSK, binary phase shifting keying) and differential quadrature phase shift keying (DQPSK, different quadrature phase shift keying) modulation technology, support 1Mb/s and 2Mb/s transmission rate; infrared transmission method works in the 850nm-950nm band, The peak power is 2W, using 4 or 16 level PPM technology, supporting 1Mb/s and 2Mb/s transmission rates.
(1) IEEE802.11b, the working frequency band is 2.4-2.4835GHz, direct sequence spread spectrum technology is adopted, 3 non-overlapping channels are used, the data transmission rate reaches 11Mbps, the indoor support range is up to 100m, and the outdoor can reach 300m; The working speed is about 5Mb/s. DSSS has strong anti-interference ability, can work on the same frequency, and is convenient to realize multiple access communication. IEEE802.11b is the mainstream WLAN standard in the early stage. It is adopted by most manufacturers. The products introduced are widely used in offices, homes, hotels, stations, airports and many other occasions. However, due to the emergence of many new WLAN standards, IEEE802.11a And IEEE802.11g are more concerned by the industry.
〔2 〕IEEE802.11a, the working frequency band is 5.725-5.85GHz, not compatible with IEEE802.11b; the data transmission rate is 6Mbps-54Mbps and can be dynamically adjusted, the transmission distance is 10-100 meters, using orthogonal frequency division multiplexing〔 OFDM) unique spread spectrum technology, using QFSK modulation, has the advantages of high bandwidth, less interference in the frequency band, more flexible deployment, and support for multiple services, but the transmission distance is short and the coverage area is small.
[3] IEEE802.11g can work in the 2.4GHz frequency band to provide a transmission rate of 11Mb/s, and can also provide a transmission rate of 54Mb/s in the 5GHz frequency band, and is backward compatible with the mixed standards of the 802.11b standard. IEEE802.11g has the main advantages of IEEE802.11b and IEEE802.11a at the same time. The coverage method is similar to IEEE802.11b, with 3 non-overlapping channels. In order to take into account the investment of existing 802.11b equipment, WLAN operators currently mostly use 802.11g.
(4) IEEE802.11i In order to strengthen the security of wireless networks and the compatibility of wireless security technologies between different manufacturers, on June 25, 2004, the IEEE working group officially passed the 802.11i standard. IEEE802.11i focuses on the following three areas: authentication, key management and confidentiality of data transmission. In order to improve authentication, 802.11i requires the use of authentication server AS (Authentication Server) and defines a more robust authentication protocol. At the same time, AS also plays the role of key distribution. In terms of confidentiality, 802.11i provides three different encryption mechanisms, namely TKIP (Temporal Key Integrity Protocol), CCMP (Counter-Mode/CBC-MAC Protocol) and WRAP (Wireless RobustAuthenticated Protocol), as well as the authentication protocol IEEE802. 1x. The operation process of IEEE802.11i is as follows: First, an exchange between the mobile station and the AP enables the two parties to reach an agreement on the set of security capabilities used; then, an exchange involving the AP and the mobile station provides security authentication. AS is responsible for distributing keys to APs, and APs in turn manage and distribute keys to mobile sites; finally, the data between mobile sites and APs is encrypted to protect data transmission. In order to ensure compatibility, IEEE802.11i fully absorbs other existing network security protocols. For example, the access control layer introduces the existing IEEE802.1x security mechanism, and the upper management layer integrates the existing LEAP and RADIUS server functions. From the perspective of hardware devices, AP only involves the WLAN bottom layer and the access control layer, the data encryption protocol of the 802.11i protocol and the access management mechanism of IEEE802.1x, and its authentication management function is completed by the authentication server and remote database. Mobile users include all three layers, involving the underlying data encryption protocol of 802.11i, the access management mechanism of IEEE802.1x, and the authentication management mechanism of IEEE802.11X/EAP. Both the client and the authentication server have the function of an authentication management layer.
(5) IEEE802.11n, this standard increases the data transmission rate of wireless local area network to above 108Mb/s, and the highest transmission rate can reach 540Mb/s. The standard is defined as a dual-frequency working mode, which includes two working frequency bands of 2.4GHz and 5.8GHz. The core technology of its physical layer is MIMO (multiple input multiple output) + OFDM wireless signal modulation.
(6) IEEE802.11ac, the standard adopts and extends the concept of 802.11n air interface, including: wider RF bandwidth (up to 160MHz), more MIMO spatial streams (up to 8 ), multi-user MIMO, and higher-order modulation (up to 256QAM), the final theoretical transmission speed will jump from 802.11n's highest 600Mbps to 1Gbps. Of course, the actual transmission rate may be between 300Mbps and 400Mbps, which is close to 3 times the current actual transmission rate of 802.11n (currently, the actual transmission rate of 802.11n wireless routers is between 75Mbps and 150Mbps).
1.3 Wireless local area network structure
In the IEEE 802.11 standard, the local area network structure is specifically divided into two standard forms: "Peer-To-Peer" and "Master-Slave". The "point-to-point" structure is used to connect PCs or portable computers, allowing each computer to move within the range covered by the wireless network and automatically establish a point-to-point connection, so that different computers can directly exchange information. In the "master-slave" structure, all workstations are directly connected to the central antenna or access point (AP: Access Point), and the AP is responsible for wireless communication management and connection to the wired network. When wireless users work in the range covered by the AP, they do not need to spend a lot of resources to find other sites, which is an ideal low-power working method. At the same time, IEEE802.11 also makes the following provisions on the physical layer, application environment and functions of the wireless LAN. At present, the topological structure adopted by the wireless local area network mainly includes three types: peer-to-peer, access and relay.
1. Peer-to-peer mode: The local area network in the peer-to-peer mode does not require a separate access device AP with the master control relay function, and all base stations can communicate with each other peer-to-peer. Not all products that claim to be compatible with the 802.11 standard have this working mode. The mode corresponding to wireless products is Ad Hoc Demo Mode. In a LAN in Ad Hoc Demo mode, a base station is automatically set as the initial station, and the network is initialized so that all base stations in the same domain (same SSID) become a local area network, and the base station cooperation function is set to allow multiple base stations at the same time send Message. In this way, in the MAC frame, the source address, destination address, and initial station address are simultaneously. At present, this mode uses the NetBEUI protocol and does not support TCP/IP, so it is more suitable for users who have not built a network or set up temporary networks, such as field operations, temporary mobile meetings, etc. 
2. Access method: This method is based on the star topology, with the access point AP as the center. All base station communications must be transferred through the AP, which is equivalent to using the wireless link as the original backbone network or a part of it. Correspondingly, in the MAC frame, the source address, destination address, and access point address are at the same time. Through the response signal of each base station, the access point AP can build a "bridge connection table" like a "routing table" inside, linking each base station and port one by one. When the signal is transferred, the AP performs by querying the "bridge connection table". 
3. Relay mode: Relay is based on the access principle, which is a Point to Point link between two APs. Due to the exclusive channel, it is more suitable for the long-distance interconnection of two LANs (high gain After the directional antenna, the transmission distance can reach 50 kilometers). Because the wireless network adopts the relay mode to have various networking modes, they are collectively referred to as the Wireless Distribution System (Wireless Distribution System). It is in this mode that the MAC frame uses four addresses, namely the source address, the destination address, the transit sending address, and the transit receiving address. The access method and the relay method support multiple network protocols such as TCP/IP and IPX, and are the main application methods of wireless networks that IEEE802.11 attaches importance to and promotes vigorously.
Chapter 2: Wireless Local Area Network Security Technology
2.1 Service Area Identifier (SSID) matching
This technology requires workstations to show the correct SSID, which is the same as the SSID of the wireless access point AP to access the AP; otherwise, the AP will refuse to connect to the subnet Connection. If an AP broadcasts its SSID to the outside, many people know the SSID of the AP, and it is easy to share it with illegal users, and the security level is seriously reduced. At present, many manufacturers support the "(ANY)SSID" method. As long as the wireless station is within the service range of a certain AP, the client will automatically connect to the AP, and this will skip the SSID password authentication, posing a great threat to network security . Therefore, SSID can be considered as a simple password authentication mechanism to achieve a certain degree of security. The support for this technology on the wireless LAN access point AP prevents the AP from broadcasting its SSID, so that the wireless workstation must actively provide the correct SSID to connect to the AP.
2.2 MAC physical address filtering
The technical principle is to manually maintain a set of MAC address lists that are allowed or not allowed to be accessed in each AP of the WLAN to achieve physical address access filtering. If there are a large number of APs, in order to achieve unified wireless network card MAC address authentication for all APs, it is necessary to record the client MAC address that needs to access the network, although APs now support centralized Radius authentication for wireless network card MAC addresses. However, this solution requires that the MAC address list in the AP must be updated at any time, which has poor scalability and is only suitable for small network scales. More importantly, the MAC address can be forged and tampered by third-party software, so it is a lower-level authorization authentication.
2.3 WEP wired equivalent confidentiality
WEP is the abbreviation of (Wired Equivalent Privacy). This technology uses the RC4 symmetric encryption algorithm developed by RSA, and all WIFI certified devices support this security agreement. Use a 40-bit encryption key to encrypt data at the link layer to ensure that the transmitted data will not be intercepted in plaintext; the user's encryption key must be the same as the AP's key to access the network. When the client tries to connect to the AP, the AP will send a challenge packet to the client. The client then encrypts the value with the shared key and sends it back to the access point for authentication and comparison. Only if it is correct can it access network resources. But there are still many shortcomings: if all users in a service area share the same key, once the key is lost, the security of the entire network will be threatened; the key is static and needs to be maintained manually, which has poor scalability; 40-bit key It is easy to crack. Although it was later modified to a 128-bit key, its security is still not high, but it can still block general data interception***.
2.4 AP Isolation
AP Isolation is similar to the VLAN (virtual local area network) of a wired network, which completely isolates all wireless client devices so that they can only access the fixed network connected to the AP. This method is used to set up Hot Spot in public hotspots such as hotels and airports to keep the connected wireless clients isolated and provide safe Internet access.
2.5 802.1X protocol
The 802.1x protocol is an access control and authentication protocol based on Client/Server. It can restrict unauthorized users/devices from accessing LAN/WLAN through an access port. The 802.1x protocol is a two-layer protocol, which does not require high overall performance of the equipment, and can effectively reduce the cost of network construction; it borrows the commonly used EAP (Extensible Authentication Protocol) in the RAS system, which can provide good scalability and adaptability to achieve Compatibility with traditional PPP authentication architecture; 802.1x authentication architecture adopts the logic function of "controllable port" and "uncontrollable port", which can realize the separation of business and authentication, and uncontrollable logic is used by RADIUS and switch The ports jointly complete the authentication and control of the user. The business packets are directly carried on the normal layer 2 packets and exchanged through the controllable port. After the authentication, the data packet is a pure data packet without encapsulation; the existing background can be used The authentication system reduces the cost of deployment and has a wealth of business support; it can map different user authentication levels to different VLANs; it can make switch ports and wireless LANs have secure authentication access functions. For a wireless LAN, a port is a channel. The ultimate goal of 802.1x authentication is to determine whether a port is available. For a port, if the authentication is successful, the port is "opened" and all packets are allowed to pass; if the authentication is unsuccessful, the port is kept "closed", that is, only 802.1x authentication protocol packets are allowed to pass.
2.6 WPA (Wi-Fi Protected Access)
WPA (Wi-Fi Protected Access) was promoted in 2003 as an intermediate standard for the transition to IEEE802.11i. Its core is 802.1x and TKIP (Temporary Key Entire Protocol). Its introduction enables 802.11b, 802.11a and 802.11g The security of the wireless devices included is guaranteed. WPA has also added the function of preventing data from being tampered with and the authentication function, and the shortcomings of WEP are solved. WPA is the first to use TKIP (Temporal Key Integrity Protocol), an encryption technology in 802.11i, which can greatly solve the security problems hidden by 802.11 originally using WEP. Many clients and APs do not support the WPA protocol, and TKIP encryption still cannot meet the encryption needs of high-end enterprises and governments. WPA2 is backward compatible with WPA and supports more advanced AES encryption, which can better solve the security problems of wireless networks. In October 2017, a security researcher announced a weakness of the WPA2 protocol, which would suffer from KRACK (Key Reinstallation AttaCK)***; the hacker can obtain the data transmitted between the STA and the AP, and many manufacturers have released relevant information. The patch fixes this vulnerability; but the image and reputation of WPA2 is still damaged, so the Wi-Fi Alliance quickly launched WPA3. In 2018, the Wi-Fi Alliance announced the largest Wi-Fi security update in 14 years, announcing the final completion of the WPA3 protocol, which brought many The new function is used to ensure the security of transmitted data to solve the security problems in WPA2.
2.7 Virtual Private Network (***)
*** (Virtual Private Network) virtual private network, in a public network, the use of tunnel transmission and encryption technology to provide users with private data transmission services, and to ensure the network of private data Safety. Its purpose is to realize the establishment of a private and secure communication channel, so that remote users can connect to the company's internal network stably and securely and access internal resources. ***It does not belong to the 802.11 standard and can be used to reduce the insecurity risk of wireless networks.
Chapter 3: Common Security Problems of Wireless Local Area Network
3.1 Physical Security
Wireless devices include stations (STA, Station) and access points (AP, Access Point). The station is usually composed of a wireless network card; the access point is usually composed of a wireless output port and a wired network interface, and its role is to provide a bridge between wireless and wired networks. Physical security is about the security of these wireless devices themselves. First of all, wireless devices have many limitations, which will potentially affect the data stored in these devices and the security of the communication links established between the devices. Compared with personal computers, wireless devices such as personal digital assistants (PDAs) and mobile phones have shortcomings such as short battery life and small displays. Secondly, although wireless devices have certain protection measures, these protection measures are always based on the minimum information protection requirements. Therefore, it is necessary to strengthen various protective measures for wireless devices.
3.2 Roaming ***
ists do not need to be physically located inside the corporate building, they can use network scanners, such as Netstumbler and other tools. The wireless network can be sniffed out with a laptop or other mobile devices on a moving vehicle. This activity is called "wardriving".
3.3 Fraudulent access point The
so-called fraudulent access point refers to an access point that is set up or exists without the permission or knowledge of the wireless network owner. Some employees sometimes install fraudulent access points, the purpose of which is to circumvent the installed security measures and create hidden wireless networks. Although this kind of secret network is basically harmless, it can construct an unprotected network, and then acts as an open door for the gangsters to enter the corporate network.
3.4 Double-faced devil***
This type of *** is sometimes called "wireless phishing". The double-faced devil is actually a fraudulent access point hidden under the name of a neighboring network. The double-faced demon waits for some blindly trusted users to enter the wrong access point, and then steal individual network data or hack computers.
3.5 Hijacking and surveillance of wireless communications
Just as in wired networks, hijacking and monitoring network communications through wireless networks is entirely possible. It includes two situations, one is wireless data packet analysis, that is, a skilled hacker uses a technology similar to a wired network to capture wireless communications. There are many tools that can capture the first part of a connection session, and the data will generally include a username and password. The hacker can then use the captured information to pretend to be a legitimate user, hijack the user's session and execute some unauthorized commands. The second case is broadcast packet monitoring. This monitoring depends on the hub, so it is rare.
Chapter 4: Introduction to Common WiFi Password Cracking
4.1 Intercepting data packets and running a dictionary
a) When the software captures data packets, only the client can connect to the wireless access point to get a useful handshake packet. After analyzing the handshake packet, running the dictionary can find the password . The speed of cracking depends largely on the computing power of the host running the dictionary.
b) The dictionary used when running the dictionary determines whether the password of the wireless access point can be successfully cracked. As long as there are enough possible password combinations in the dictionary, it can be cracked theoretically, but it takes longer . That is to say, if the password is complicated enough, it will not necessarily be included in the dictionary, so that the *** person will spend a lot of time capturing the package, and running the package will be crazy.
4.2
Principle of pin code exhaustion
PIN code exhaustion cracking method is to exhaust the 8-digit personal identification number (PIN) of the WPS function of the wireless access point. The so-called WPS (Wi-Fi Protected Setup) is the Wi-Fi security protection setting standard. The certification project organized and implemented by the Wi-Fi Alliance is mainly dedicated to simplifying wireless LAN installation and configuration of security performance. WPS is not a new security feature, it just makes existing security technology easier to configure. Provides a fairly simple encryption method. Through this function, not only can Wi-Fi devices and wireless routers with WPS function be quickly interconnected, but also an eight-digit string will be randomly generated as a personal identification number (PIN) for encryption. In WPS encryption, the PIN code is the only requirement for access between network devices, and other identification methods are not required, which makes brute force cracking feasible. Secondly, the 8th digit of the WPS PIN code is a checksum, so only the first 7 digits need to be calculated. In this way, the number of unique PIN codes is reduced by one level to the 7th power of 10, which means there are 10 million changes. When implementing PIN identification, the access point (wireless router) actually finds out whether the first half (first 4 digits) and the second half (last 3 digits) of this PIN are correct. When the first PIN authentication connection fails, the router will send back an EAP-NACK message to the client, and through this response message, the *** person can determine whether the first half or the second half of the PIN is correct. In other words, the hacker only needs to find a 4-digit PIN and a 3-digit PIN from the 7-digit PIN. The password may have 11000 (10 to the 4th power + 10 to the 3rd power) variety of changes.
Analysis
a) PIN code cracking Use the personal identification code in the wireless access point WPS quick interconnection to perform exhaustive cracking. There is no need for other hosts to communicate with the wireless access point, and there is no need to worry about how complicated the password setting is.
b) Even if the owner of the wireless access point changes the password, the PIN code remains the same. We can still pass the verification of the wireless access point by using the PIN code and easily get the new password in the connection information.
c) The PIN code in WPS has only 8 all-digit passwords, there are 108 possible passwords, and the 8th digit is a checksum (checksum), as long as you find a 4-digit password from the 7-digit PIN A number of PINs and a 3-digit PIN make a total of 104+103 possible password combinations. In this way, the hacker only needs to test 11,000 times at most, which greatly shortens the time to crack.
4.3 The FeedingBottle cracking method is
also milk bottle cracking. The working principle is very similar to that of intercepting data packets and running a dictionary. Limited to the comprehensiveness of the dictionary and whether there is customer service access during packet capture, the best way to avoid this type of cracking is to set a sufficiently complex password and enable MAC address verification.
4.4 All kinds of wifi password cracking software
software will check "automatic sharing hotspot" by default after installation. It is this option. When connected to WiFi, the information will be automatically shared and saved to the software database, thus integrating a more powerful Wifi password database. When more users share their hotspots, the efficiency of using wifi cracking software in this area will be higher.
Chapter 5: Basic security configuration of WLAN
- 1 Physical protection In
life, most wireless APs are deployed close to the office environment or outside the house. From the previous introduction to wireless network security, it can be seen that wireless access points arranged in this way are vulnerable to malicious actors. Or be stolen directly. At present, most wireless devices provide a reset button to reset the AP, so that the stolen AP can be easily reused. For enterprise users, when designing and planning the wireless network architecture, placing the AP in an inaccessible location can greatly protect the security of the wireless network; and in order to prevent suspicious persons such as spies from illegally entering the computer room and building illegal APs Or damage the existing AP, etc., should set up strict security and confidentiality rules and regulations in the computer room, strictly limit the list of persons who can enter the central computer room, and install monitoring equipment.
5.2 Upgrade hardware devices
Usually the latest equipment products are relatively safe. As a wireless security manager, you should always pay attention to the latest vulnerabilities and related patches released by the wireless device manufacturer’s website, and install the security updates or Upgrade program. As shown in the page of the fast wireless router upgrade
5.3 Modifying the SSID
Now most APs (wireless access points) broadcast their SSID by default, and the client can only connect to the wireless network after receiving this parameter or manually setting the same SSID as the AP. If broadcasting the SSID is prohibited, general roaming users cannot connect to the wireless network if they cannot find the SSID. When setting the AP's SSID, you need to avoid using generic, directional names, such as the company name "chinanet", the default name of the access point "TP-link", and the test name "testap". SSID, as a way of primary access network authentication, increases its complexity during setting and cancels broadcast SSID.
- 4 Turn on behavior control
The wireless access devices introduced now generally have behavior control. Conditions for accessing the network are formulated, and the right to access the network can only be obtained after the established conditions are met. In behavior control, the MAC address is managed, the physical address (MAC) of the wireless network card that is legally accessed is configured through the access control list, and the access target address is managed, and the time of access to the network is managed. As shown in the behavior management of the fast router
5.5 Using a new generation of wifi security protocols
From the previous introduction of their encryption methods and password cracking, although WPA uses the encryption technology TKIP (temporal key integrity protocol) in 802.11i to greatly solve the security problems hidden by WEP. However, as an upgraded version of WPA, WPA2 has been improved in security. Now almost all clients and wireless access points support the WPA protocol, but the TKIP encryption still cannot meet the demanding users. WPA2 is backward compatible with WPA and supports AES encryption at the same time, which can better solve the security problems of wireless networks. WPA-PSK should be enabled instead of WEP during configuration. The new WAP3 protocol upgrades WiFi security in four different dimensions. Among them, the encryption level has been upgraded to the 196-bit AES advanced encryption standard, the dictionary*** is no longer available, the security of the Internet of Things devices is improved, and the encryption of personalized data.
5.6 Modify the default management address and management account
Most users neglect to modify the default management address and management account. The default wireless access point password should be modified during the setting, and the login password should be set to more than 10 digits to ensure the complexity of the password. , The password should contain at least any 3 of uppercase letters, lowercase letters, numbers and special symbols. 
And modify the management address, from the MAC address to limit the management rights of the wireless access point
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