Hotel Lock Technology Guide: Card Types, Frequencies & Standards

Understanding the technology behind hotel locks helps with troubleshooting, upgrades, and making informed purchasing decisions. This guide covers the major technologies used in hotel access control systems.

Technology Timeline

Card Technology Comparison

Magnetic Stripe Technology

How it works: Data is stored on a magnetic strip on the card. The lock reads this data when the card is swiped or inserted.

Advantages:

• Low card cost
• Simple encoding equipment
• Widely understood technology

Disadvantages:

• Cards demagnetize easily (cell phones, wallets, other cards)
• Physical contact causes wear on both card and reader
• Lower security (data can be copied)
• Shorter card lifespan

Still in use: Some legacy systems, particularly older Onity HT22 installations

RFID Technology (13.56 MHz)

How it works: Cards contain a small chip and antenna. When held near the reader, the reader's electromagnetic field powers the chip, which transmits its data wirelessly.

Advantages:

• No physical contact required (tap or wave)
• More durable than magnetic stripe
• Faster read times
• Multiple applications possible on one card

Disadvantages:

• Higher card cost than magnetic stripe
• Requires compatible readers

Common standards: ISO 14443 Type A (MIFARE), ISO 14443 Type B, ISO 15693

MIFARE Card Types

MIFARE is the most common RFID technology in hotel locks. Originally developed by Mikron (Austria), it's now owned by NXP Semiconductors.

MIFARE Classic 1K

• Memory: 1,024 bytes (16 sectors)
• Security: Proprietary encryption (considered legacy)
• Use case: Standard hotel key cards, access control
• Compatibility: Most hotel lock systems including Onity, SALTO, Dormakaba

MIFARE Classic 4K

• Memory: 4,096 bytes (40 sectors)
• Security: Same as Classic 1K
• Use case: Multi-application cards (room + amenities + loyalty)

MIFARE Plus

• Memory: 2K or 4K options
• Security: AES 128-bit encryption
• Use case: Properties requiring higher security
• Note: Backward compatible with Classic infrastructure

MIFARE DESFire EV1/EV2/EV3

• Memory: 2K, 4K, or 8K options
• Security: AES encryption, mutual authentication
• Use case: High-security applications, multi-application cards
• Common in: Upscale and luxury properties

MIFARE Ultralight

• Memory: 64 bytes (limited)
• Security: Basic
• Use case: Single-use or limited-use applications
• Cost: Lower than other MIFARE variants

125 kHz Proximity Cards

How it works: Lower frequency RFID technology. Cards transmit a fixed ID number when powered by the reader.

Advantages:

• Very low card cost
• Simple technology

Disadvantages:

• Read-only (cannot store changing data)
• Lower security (easily cloned)
• Longer read range can be a security concern

Note: Not commonly used in modern hotel installations due to security limitations.

Mobile Key Technology

Mobile key systems use smartphones instead of physical cards.

Bluetooth Low Energy (BLE)

• Range: Up to 30 feet (configurable)
• Power: Low battery consumption
• Compatibility: Most modern smartphones
• How it works: Phone and lock establish encrypted connection via Bluetooth

Near Field Communication (NFC)

• Range: 1-4 centimeters
• Power: Very low
• Compatibility: Most Android phones, newer iPhones
• How it works: Phone held very close to reader, similar to contactless payment

Comparison

Lock System Compatibility

Different lock manufacturers support different card technologies:

Choosing the Right Technology

Consider these factors when evaluating lock technology:

1. Existing infrastructure - What's already installed?
2. Card cost vs. volume - High turnover properties benefit from durable cards
3. Security requirements - What level of encryption is needed?
4. Guest expectations - Do your guests expect mobile access?
5. Multi-application needs - Will cards be used for more than room access?
6. Future planning - Is the technology upgradeable?

Common Compatibility Issues

MIFARE Classic with newer readers: Some newer readers default to higher security modes and may not read Classic cards without configuration.

125 kHz cards on 13.56 MHz systems: These are completely incompatible - different frequencies.

Mobile key on older locks: Requires BLE-enabled hardware, which may require lock replacement or retrofit modules.

Mixed card populations: Properties transitioning between technologies need encoders and readers that support both formats.

Need Help With Your Lock Technology?

RevKey Systems can help you:

• Assess your current lock technology
• Plan upgrades to newer systems
• Source compatible cards and equipment
• Train staff on different card types
• Troubleshoot compatibility issues

Contact us through our support page for assistance with your lock systems.