|Ⅱ How a wireless router works?|
|Ⅲ Wireless route parameters|
|Ⅳ Advantages of wireless route|
A wireless router is like an extended product that combines a simple wireless AP and a broadband router into one. It has all the functions of a simple wireless AP, such as supporting DHCP clients, supporting VPN, firewall, supporting WEP encryption, etc... It also includes a network address translation (NAT) function to support network connection sharing for LAN users. It can realize the Internet connection sharing in the home wireless network, and realize the wireless shared access of ADSL, Cable modem, and residential broadband.
The wireless router can be directly connected to all the ADSL MODEM or CABLE MODEM connected to the Ethernet, or it can be re-connected through the switch/hub, broadband router, and other LAN methods when in use. It has a built-in simple virtual dial-up software that can store user names and passwords to dial-up Internet access and can provide automatic dial-up functions for dial-up Internet access ADSL, CM, etc... In addition, wireless routers generally have relatively more complete security protection functions.
A wireless router is used to connect multiple logically separated networks. The so-called logical network represents a single network or a subnet. When data is transmitted from one subnet to another, it can be done through a router. Now suppose that when a user A1 in network A wants to send a request signal to user C3 in network C, the working principle is as follows:
Step 1: User A1 sends the address C3 of the destination user C3, together with the data information, to all nodes in the same network. When the router A5 port detects this address, it analyzes that the destination node sent is not in the network segment so it route and forwards the destination node and receives the data frame.
Step 2: After the router A5 port receives the data frame of user A1, it first extracts the IP address of the destination user C3 from the header, and calculates the best path to user C3 according to the routing table. Because it is known from the analysis that the A5 port of the router directly sent to the C5 port of the router should be the best way for signal transmission.
Step 3: The C5 port of the router takes out the IP address of the destination user C3 again, and finds out the host ID number of C3. If there is a switch in the network, you can send it to the switch first, and then find out the specific network node location according to the MAC address table; If not, send the data frame directly to user C3 according to the host ID in its IP address, so that a complete data communication forwarding process is also completed.
By 2013, the mainstream protocol standard supported by wireless router products is IEEE 802.11n and is compatible with 802.11g, 802.11b. Here you should first know the meaning of this standard. The "IEEE" of the protocol is an international wireless standard organization that is responsible for electrical and electronic equipment, test methods, original devices, symbols, definitions, and test methods.
The latest wireless router now has supported the 802.11ax protocol. In 2018, WiFi Alliance (this is a commercial alliance consisting of vendors, unlike IEEE), named the 802.11ax protocol WiFi6.
802.11a: The first generation WiFi protocol, working in the 5GHz band, the highest rate 54Mbps;
802.11b: The highest rate is 11Mbps, working in the 2.4GHz band;
802.11g: It can be seen as a frequency band of 11A in 2.4GHz, and the highest rate is also 54Mbps;
802.11n: This is WiFi4, 11N is considered a big increase in WiFi, and has quality improvement from the rate. At the same time, 2.4GHz and 5GHz are supported.
802.11ac: WiFi5, further enhance bandwidth, modulation, mimo, etc., working at 5GHz, and part of the chip also supports 2.4GHz 11ac.
802.11ax: This is WiFi-6, supports 2.4GHz, and 5GHz, and further improved on the basis of WiFi-5.
Similar to a wired network, the transmission rate of a wireless network refers to its ability to receive and send data under a certain network standard; however, in a wireless network, this performance has a lot to do with the environment. Because in the wireless network, the data transmission is carried out through the signal, and the actual use environment will more or less cause certain interference to the transmission signal.
The actual transmission speed of the wireless LAN can only reach less than half of the product's nominal maximum transmission speed. For example, the theoretical maximum speed of 802.11b is 11M. Through the test, in the case of a good wireless network environment, it can transmit 100MB. The file needs about 3 minutes; and in the same environment, it only takes about 30 seconds to transfer a 100MB file if it is replaced by a product that supports 802.11g.
This is also one of the important parameters of the wireless router, ie "effective working distance". This means that other computers can wirelessly connect only within the signal coverage of the wireless router.
"100 meters indoors, 400 meters outdoor" is also an ideal value, which will vary from the network environment. Usually, there is a good wireless signal in 50 meters in the room, and the outdoor general can only reach About 100-200 meters. The wireless router signal is strongly affected by the environment.
We can understand this simply: compare a wireless router to a daily communication tool-a mobile phone. The frequency used by the mobile phone is generally between 800 and 2000MHz, while the working frequency of the wireless router and the mobile phone is similar, 2.4GHz. In 2013, there is a trend to develop to 5.8GHz.
Wired and wireless connection of wireless routers
The wireless router allows you to enjoy the extremely fast Internet life anytime and anywhere under the guarantee of WIFI security, and will never drop the line. Intelligent management allows you to freely enjoy worry-free Network connection, whether in outdoor meetings, exhibitions, venues, factories, or homes. Through the USB2.0 interface, this hardware allows your desktop computers and notebooks to enjoy wired or wireless network cable networks. The router can even be used as a printer server, Webcam, or FTP server to realize network sharing of hardware.
Using a wireless router, you can connect a 3G/HSDPA USB modem to its built-in USB interface, which allows you to connect to networks exceeding 3.5G/HSDPA, 3.75G/HSUPA, HSPA+, UMTS, GDGE, GPRS, or GSM networks. The download rate is up to 14.4Mbps. When the wired network connection fails, through the built-in automatic fault conversion function, you can quickly and smoothly connect to the wireless network, ensuring maximum connection and minimum interference. When the wired network is restored, it can also automatically connect again, reducing or minimizing connection costs. This feature is particularly suitable for office environments, where continuous network connectivity is very important.
The USB interface of the wireless router can be used as a multi-function server to help you build your own network. When you are out, you can use the office printer, monitor your house via Webcam, share files with colleagues or friends. You can even download FTP or BT files.
The unique 3G management center is a multi-functional display tool that visually displays the signal conditions, allowing users to make the most of their connections. You can monitor bandwidth using upload speed and download speed. This tool can calculate the total amount of data used per month or the total amount of hours.
In the wireless network, the antenna can achieve the purpose of enhancing the wireless signal, which can be understood as an amplifier of the wireless signal. Antennas have different radiating or receiving capabilities for different directions in space. Depending on the directivity, antennas have two types: omnidirectional and directional.
Omnidirectional antenna: On a horizontal plane, the antenna that has no maximum direction for radiation and reception is called an omnidirectional antenna. Since omnidirectional antennas are non-directional, they are mostly used in the central station of point-to-multipoint communication. For example, if you want to establish a wireless connection between two adjacent buildings, you can choose this type of antenna.
Directional antenna: The antenna with one or more directions with the greatest radiation and reception capabilities is called a directional antenna. The energy of the directional antenna is concentrated, and the gain is higher than that of the omnidirectional antenna, which is suitable for long-distance point-to-point communication. At the same time, due to its directivity, the anti-interference ability is relatively strong. For example, in a residential area, when you need to establish a wireless connection across several buildings, you can choose this type of antenna.