# Access Cards for Doors: The Ultimate Guide to Modern Access Control ## Understanding Access Control Cards Access cards for doors have revolutionized how we secure buildings and manage entry permissions. From my experience working in facility management, I've seen firsthand how these systems evolve from simple keycards to sophisticated multi-technology solutions. The transition from traditional keys to electronic access cards not only enhanced security but also provided unprecedented control over who enters specific areas and when. ## Types of Access Cards for Doors ### Magnetic Stripe Cards These were among the first electronic access cards I encountered in my career. While gradually being phased out in favor of more secure technologies, they're still found in some legacy systems. The magnetic stripe contains encoded data that readers interpret to grant or deny access. ### Proximity Cards (RFID) Proximity cards use radio frequency identification (RFID) technology. I've personally implemented these in several office buildings—users simply hold the card near the reader without physical contact. These come in two main frequencies: - 125 kHz (low frequency) - 13.56 MHz (high frequency) ### Smart Cards Smart cards contain embedded microprocessors or memory chips, offering enhanced security features. In my work with government facilities, I've deployed smart cards that support encryption and multiple applications beyond just door access. ### Biometric Integration Cards Some advanced systems combine card technology with biometric verification. I once managed a research facility where employees used cards that also stored fingerprint templates for two-factor authentication. ## Technical Specifications for Access Cards **TIANJUN ProX-Smart Card (Model TJ-PSC2023)** - Dimensions: 85.6 × 54.0 × 0.76 mm (ISO/IEC 7810 ID-1 standard) - Chip: NXP Mifare DESFire EV3 (MF3DHx3) - Memory: 8KB EEPROM - Security: AES-128 encryption - Frequency: 13.56 MHz - Communication: ISO/IEC 14443 Type A - Operating Temperature: -25°C to +70°C - Expected Lifespan: 10 years or 100,000 read/write cycles **TIANJUN Ultra-Prox Card (Model TJ-UPC2023)** - Dimensions: 85.6 × 54.0 × 0.84 mm - Chip: Temic e5551 (125 kHz) - Read Range: Up to 15 cm - Operating Frequency: 125 kHz ± 5 kHz - Data Capacity: 264 bits - Programming: Factory programmed or field programmable options - Material: PVC with optional polyester overlay *Note: These techni