NXP Mifare Classic EV1 4K S70 Card

Descripción

Key Technical Features:

1. Storage Capacity and Structure
Total capacity is 4KB (32Kbit) EEPROM, divided into 40 sectors:
The first 32 sectors (Sectors 0–31) are “small sectors,” each containing 4 data blocks, totaling 64 bytes;
The last 8 sectors (Sectors 32–39) are “large sectors,” each containing 16 data blocks, totaling 256 bytes.
Each sector has independent key A and key B (6 bytes each) and access control bits, enabling fine-grained access control.

2. Security Mechanism
Employs NXP’s proprietary Crypto1 encryption algorithm for two-way authentication, adhering to the ISO/IEC 9798-2 three-way handshake protocol.
Although it possesses logical encryption capabilities, the algorithm was successfully cracked by researchers in Germany and the United States in 2008–2009, posing a risk of cloning and unauthorized reading.
Therefore, its security is lower than that of CPU cards using public encryption standards (such as 3DES and AES), making it suitable for low to medium security requirements.

3. Physical and Communication Parameters
Operating distance: Typical 2.5–10cm, depending on reader performance;
Communication rate: 106Kb/s;
Supports anti-collision mechanisms, allowing multiple cards to operate simultaneously;
Data retention up to 10 years, write/erase cycle exceeding 100,000 times.

4. UID and Compatibility
Supports 4-byte or 7-byte UIDs, but different lengths may cause reader compatibility issues;
The EV1 version improves the manufacturing process and stability based on the original S70, enhancing compatibility and reliability with existing systems.