There are several forms of biometric identification employed in access control: fingerprint, hand geometry, iris, Voice Recognition, and facial recognition. Biometric technology has been promoted for its ability to significantly increase the security level of systems. Proponents claim that the technology eliminates such problems as lost, stolen or loaned ID cards and forgotten PINs.[citation needed]

A reader radiates a 1" to 20" electrical field around itself. Cards use a simple LC circuit. When a card is presented to the reader, the reader's electrical field excites a coil in the card. The coil charges a capacitor and in turn powers an integrated circuit. The integrated circuit outputs the card number to the coil, which transmits it to the reader.


In the 1-to-1 mode a user must first either present an ID card or enter a PIN. The reader then looks up the template of the corresponding user in the database and compares it with the live scan. The 1-to-1 method is considered more secure and is generally faster as the reader needs to perform only one comparison. Most 1-to-1 biometric readers are "dual-technology" readers: they either have a built-in proximity, smart card or keypad reader, or they have an input for connecting an external card reader.

In the 26-bit Wiegand format, bit 1 is an even parity bit. Bits 2–9 are a facility code. Bits 10–25 are the card number. Bit 26 is an odd parity bit. 1/8/16/1. Other formats have a similar structure of a leading facility code followed by the card number and including parity bits for error checking, such as the 1/12/12/1 format used by some American access control companies.
Your psychic reading can give you the chance to see if you are heading down the right track or if trouble is lurking around the corner. Psychics can reaffirm something you already know, or give you new insights and point of view. After your reading, you will have a greater sense of clarity and control over everything life has been sending your way.
Many Windows users come across the SD card reader not working error after the Windows 10 update and fail to get access to their important SD card data. It's a very nerve-wracking but also common issue that Windows 10 is stuck on the “SD card not recognized” problem. Don’t be worried. In this Windows 10 guide, we’ll walk you through top 4 ways to tackle this card reader not working issue.
Biometric templates may be stored in the memory of readers, limiting the number of users by the reader memory size (there are reader models that have been manufactured with a storage capacity of up to 50,000 templates). User templates may also be stored in the memory of the smart card, thereby removing all limits to the number of system users (finger-only identification is not possible with this technology), or a central server PC can act as the template host. For systems where a central server is employed, known as "server-based verification", readers first read the biometric data of the user and then forward it to the main computer for processing. Server-based systems support a large number of users but are dependent on the reliability of the central server, as well as communication lines.
There are two types of smart cards: contact and contactless. Both have an embedded microprocessor and memory. The smart card differs from the proximity card in that the microchip in the proximity card has only one function: to provide the reader with the card's identification number. The processor on the smart card has an embedded operating system and can handle multiple applications such as a cash card, a pre-paid membership card, or an access control card.