The role and basic types of access control readers

[ Huaqiang Security Network News ] The current access control card reader is developing very fast, and the card reader is a product that performs data exchange between different digital products. As the name suggests, a reader is a device that reads a memory card. The role of access control card readers With the rapid development and popularity of digital products, we often exchange data between different digital products. Card readers are products that perform such functions. As the name suggests, a reader is a device that reads a memory card.
The access control card reader is a device for reading data (biometric information) in a card. It is an access control component that directly contacts the user. Its function is to read and identify the identity information of the entrant. Typically, identity information can be card number, personal password, fingerprint or other important information used to identify and prove an individual's identity.
The card reader is an important part of the access control system. It is the key device for the signal input of the access control system. If the access control system is compared to a person, the card reader is like a human eye. It is related to the stability of the entire access control system. If an access control system controller and electric lock are good, if the quality of the card reader is problematic, it will also cause the door to open, which will affect the acceptance and use of the project.
The type of access control card reader technology can be divided according to radio frequency and ISO standards:
Low frequency 125KHz: Using radio wavelength 125KHz, standard proximity technology, has been gradually replaced by high frequency technology as a relatively old standard.
High frequency 13.56MHz: The radio wavelength is 13.56MHz, which allows reading, writing and encryption to improve security. Due to the higher communication speed, it is more suitable for biometric identification and processing special security and anti-counterfeiting certification. High-frequency technology has become the mainstream development trend in the current market.
There are two more popular international standards in high frequency technology:
ISO14443: International standard non-contact technology, usually reading distances up to 10 cm. The advantage is that the processing speed is fast, and it is suitable for information transmission with a large amount of data, such as biometric technology. ISO14443 is further subdivided into two standards, A and B. 14443A is more popular in the transportation industry, and 14443B is more popular in the banking industry.
ISO15693: International standard non-contact technology, VICINITY technology, usually reading distance greater than 10 cm. Its advantages are longer read range and lower power consumption.
Another division is the operating mode of the reader:
The so-called operating mode refers to the data transmission format between the card reader and the controller.
· Wiegan's majority of manufacturers are using this model. The Wiegand data format passes the specific number of the identity card to the controller through a series of numbers 0 and 1 from the reader through the two data lines. This transfer process is one-way and can only be transmitted from the card reader.
· F/2F (Frequency/Twice the Frequency), also known as Manchester decoding. It is a unique model owned by GE. The F/2F format transfers data over a single data line. The data is transmitted as a string of 0's and 1's, but the first ten digits remain at zero. This is to monitor the bandwidth of the reader for the controller and then determine if the subsequent digit is 1 or 0. Monitoring F/2F is the most complex functional mode. The patented F/2F mode monitors two-way communication from the reader to the controller. Every second, the reader will send a "I am still alive" signal to the controller. The controller immediately sends back a receipt message to confirm that the communication is clear. However, if the line is cut or shorted, the reader will not be able to communicate with the controller. The reader still sends a message every second. If the reader fails to receive the receipt information, it will instead send 3 messages per second. If the receipt is not received for more than 1 second, the reader will issue a monitored alarm, the red indicator will flash, and the reader will beep. Because the reader and controller communicate every second, an open or short circuit is quickly detected and an alarm is triggered, creating a very secure system.