Foreword:
With regard to wireless network knowledge, it is necessary to know that the current wireless coverage system has become an indispensable subsystem for weak current systems, especially public construction projects, which can be said to be mandatory systems.
text:
What is an AP?Answer: AP--Wireless Access Point (AP) is the HUB in traditional wired networks and the most commonly used device for building small wireless LANs. The AP is equivalent to a bridge connecting the wired network and the wireless network. Its main function is to connect the wireless network clients together, and then connect the wireless network to the Ethernet to achieve the purpose of wireless coverage of the network.
AP is also divided into "thin" and "fat"?
Thin AP (FITAP):
Also known as wireless bridges, wireless gateways, also known as "thin" APs.
The popular understanding of the thin AP: itself can not be configured, requires a dedicated device (wireless controller) for centralized control management configuration.
The "controller + thin AP + router architecture" is generally used for wireless network coverage, because when the number of APs is large, the configuration is managed only by the controller, which simplifies a large workload;
Fat AP (FATAP)
The so-called fat AP in the industry is also known as a wireless router. Wireless routers are different from pure APs. In addition to wireless access, they generally have two interfaces, WAN and LAN. They support address translation (NAT), support for DHCP server, DNS and MAC address cloning, and VPN access, firewall, etc. Features.
What is AC?A: The Wireless Access Point Controller is a network device used to centrally control the controllable wireless APs in the LAN. It is the core of a wireless network and is responsible for managing all wireless APs in the wireless network. : Distribute configuration, modify related configuration parameters, RF intelligent management, access security control, etc. (All current ACs and APs in the market are all managed by the same manufacturer)
What is POE power supply and what is a POE switch?A: The POE (PowerOver Ethernet) POE is also known as a LAN-based power system (PoL, Powerover LAN) or Active Ethernet. It is sometimes referred to as Power over Ethernet. It refers to the existing Ethernet. The network Cat.5 cabling infrastructure can transmit data signals for some IP-based terminals (such as IP phones, WLAN access points APs, network cameras, etc.) without any changes. Provides DC power supply technology. POE technology can ensure the normal operation of existing networks while minimizing costs while ensuring the security of existing structured cabling.
Market popular application--POE switch: In addition to providing the transmission function of the ordinary switch, the POE switch can also provide power supply to the other end of the network cable. Power supply + data transmission integration, no need to add power supply module or POE power supply module to supply power to the equipment, a Cat.5 line to complete all work.
POE power supply "standard" and "non-standard" differences
• Standard poe: According to the IEEE802.3af/at specification, it is necessary to first detect the 25K characteristic resistance of the receiving end, perform handshake, and successfully transmit the power before it is powered; otherwise, only data (data).
• Example: Plug the POE power supply into the computer network card, it will not burn the computer network card and only can access the Internet because the data can pass.
• Non-standard POE: Also called strong supply type, the AC power is supplied when the power is on; the power terminal is not detected first, and the handshake is not performed, and the power is directly supplied by 48V or 54V.
• Example: Plug the POE power supply into the computer network card to access the Internet normally, but do not negotiate direct power supply 48 or 54V, which may burn the device.
The market is roughly divided into several output voltages (DC) such as 48V, 24V and 12V.
What software and hardware are required to deploy a wireless project?Basic hardware: router POE switch AC controller wireless AP
High-end hardware: firewall router traffic and behavior management bypass main switch floor switch POE switch AC controller wireless AP
Is the power of the AP as large as possible?A: No, the higher the power of the AP, the higher the signal strength of the transmitted signal. The literal understanding will lead you to the wrong area. The stronger the signal, the better, but the signal is strong for itself, the whole wireless network. The medium transmission signal is both sides. Both the transmitting end and the receiving end transmit data to each other. The signal at the transmitting end is too strong, which will inevitably affect the data transmitted by the receiving end. This will cause network transmission delay or packet loss.
Popular understanding: In one space, you and another person are talking at the same time, the voice of the other party is too big, your voice is very small, it will cause the other party to hear what you are saying, thus affecting the quality of the call.
What are the key points and the most important things to note in a large wireless project?
Key points of wireless network engineering:design
The actual construction drawing, to determine the position of the wiring, need to consider such as: concealment, damage to the building (features of the building structure), use of the existing space while avoiding the power line and other lines, the cable in the case of the scene, etc. Necessary and effective protection needs.
Router location
The router is generally used in the weak underground room (away from the strong electricity room to avoid strong electromagnetic interference), pay attention to ventilation, keep dry, it is best to have a cabinet, put together with the core switch.
POE power switch location
POE switch location selection should be reasonable, located in the middle of the AP point, reducing the cost of routing and shortening the distance from the switch to the AP.
AP location selection
The point of the AP is arranged in the center of the selected scene, and is radiated to the periphery. The coverage of AP components should be overlapped to reduce signal dead zones. The distance between the AP and the POE switch should not exceed 80 meters (the original Amp network cable is an example)
Laying of network cable
As the transmission carrier of the network signal, the network cable should pay attention to the protection of the line during the laying process. Do not break or dead corners. If necessary, wear the iron pipe or place it in the roof bridge. Special attention is paid to the principle of high voltage wires to reduce interference with signals.
Practical operation and post-maintenance angle considerations:
a. External network and routing: The external network cable is in place to ensure the normal network access conditions, and the route is connected to ensure that the route itself can communicate normally. During the construction, the main exchange and the construction floor exchange are connected to ensure the normal communication of the backbone network.
b. Debugging the intercom: In the commissioning phase, a set of intercom equipment needs to be seconded with the mall to facilitate debugging.
c. During the construction and commissioning phase, sufficient spare parts must be reserved for AP, switch, network cable, and other construction and debugging hardware.
d. Construction drawing: Before each construction, please ask the construction party to give us two construction drawings.
Construction network topology map: requirements, detailed floor switches, routing information and location, each layer of AP and other hardware and connection methods.
Construction equipment connection line identification map: requirements, routing and switch and AP connection information, corresponding ports, etc. All connection lines are theoretically approximate network line length (including between road-switch-AP).
e, construction wiring and line marking planning:
Information identification record: AP point Mac information record: When the construction party places the AP location, it needs to record the floor number and location number of the AP and the corresponding Mac information (note the corresponding floor plan AP number, for example: 1st floor 1st mac information format is 1F- 1 : AC: 11:22:33:44:AP ). This information is uniformly recorded on the floor plan of the Word document floor store by the floor distribution or directly recorded to the free space on the side of the construction drawing for convenient maintenance.
Line mark identification record:
(1) Input and output lines on the switch side: It is necessary to indicate which floor and location number of the AP is connected to the identification or serial number. (Note that the corresponding floor plan AP number, for example, the 1st floor and 1st format is 1F-1), The incoming line of the external network should also be wired: it needs to be marked as "external network access."
(2) Interconnection between all floor switches: At the head end of the line interconnection line of the switch, it is necessary to indicate the source of the identification or serial number. (Note that the upper floor and switch label are written, for example: 1st floor 1st switch, format 1F-1 SW)
On-site viewing of installed APs is not powered, and works fine:
After the construction of the construction personnel is completed, all the APs are inspected and the power is normal. When the power is on, the green indicator light on the AP is on. If the route is in place and running, the software can detect whether the AP normally transmits signals and access the Internet.
If the above information is completely clear, then no construction personnel are required to be on site. If the above information is completely unclear, the construction personnel should cooperate with the construction personnel every time.
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