# NTAG 424 DNA Tamper-Evident Tags — AES-128 NFC

URL: https://proudtek.com/products/rfid-labels/ntag424-dna-tamper-evident-tag/
Source URL: https://proudtek.com/products/rfid-labels/ntag424-dna-tamper-evident-tag/
Generated: 2026-03-16T01:42:30.697Z
Kind: product
Publisher: Proud Tek Co., Limited
Author: Proud Tek Co., Limited
Credentials: ISO 9001:2015, ISO 14001:2015, RoHS Compliant, CE Marking, REACH Compliant
Image: https://proudtek.com/landing-images/ntag424-dna-tamper-evident-tag.jpg
Image Alt: NTAG 424 DNA tamper-evident NFC tag for anti-counterfeiting and product authentication

## Description
This NXP secure NFC chip family is NXP's flagship NFC sticker chip for product authentication: AES-128 mutual authentication plus Secure Dynamic...

## Procurement Snapshot
- Best fit: Best for asset tagging, packaging, authentication, access control, and smart-label projects.
- Key options: Form Factor: Adhesive label format for direct application to objects or packaging.
- Customization: Confirm artwork, encoding, material, chip, and finish requirements before quoting.
- Quote checklist: Confirm mounting surface, adhesive or on-metal requirements, and expected reading distance. Adhesive label format for direct application to objects or packaging. Share target chip or protocol, quantity, format or size, print or encoding...

## Key Specs
- Form Factor: Adhesive label format for direct application to objects or packaging.

## FAQ
- Q: What makes NTAG 424 DNA impossible to clone?
  A: NTAG 424 DNA uses AES-128 Secure Dynamic Messaging (SDM). Every tap generates a cryptographically unique URL parameter derived from the tag's secret AES key, UID and a monotonically incrementing read counter. A counterfeiter copying the URL from one tap cannot reuse it (it is single-use), cannot predict the next one (AES-128 is computationally infeasible to break), and cannot extract the key from the chip (the key is write-only). Cloning is mathematically infeasible without the secret key.
- Q: Does the consumer need to download an app to verify the tag?
  A: No. NTAG 424 DNA SDM works with any NFC-enabled smartphone's native NFC reading function. The tag opens a standard HTTPS URL in the consumer's mobile browser. No app download required. The SDM authentication code is passed as a URL parameter and validated on your backend server transparently. The consumer sees your branded verification page.
- Q: What happens when the tamper-evident loop breaks?
  A: When the sticker is peeled from its surface, the tamper loop antenna bridge breaks and the chip permanently records this event in its CTTES (Counter Tamper Tamper Event Status) register. This register is read-only and cannot be reset. Even if the sticker is re-adhered or the physical antenna bridge is somehow reconnected, the digital tamper flag remains permanently set and is reported on every subsequent authentication tap.
- Q: How do you handle AES key management for large deployments?
  A: Proud Tek generates a unique diversified AES-128 key for each tag using a master secret and the tag's UID per NXP AN10922 CMAC-AES. The master key never leaves Proud Tek's secure encoding facility. You receive an encrypted CSV mapping each UID to its diversified key for import into your verification backend. For ongoing production, we support re-use of the same master key (so new production batches integrate with your existing backend without changes) or rotation to a new master key with a separate key set.
- Q: What is the minimum order for NTAG 424 DNA tamper-evident tags?
  A: 1,000 pieces. This MOQ reflects the AES key provisioning setup cost and tamper-loop production requirements. For evaluation, we can provide 50-100 non-provisioned NTAG 424 DNA samples for development and testing. Contact us for pricing on sample sets.
- Q: Can NTAG 424 DNA tags be used on metal surfaces?
  A: Standard NTAG 424 DNA stickers are designed for non-metal surfaces. For metal surface applications requiring NTAG 424 DNA authentication, we offer an anti-metal NTAG 424 DNA variant with a ferrite spacer layer between the antenna and the metal substrate. Contact us for availability and pricing as this is a custom product.
- Q: How does NTAG 424 DNA support the EU Digital Product Passport?
  A: NTAG 424 DNA's 5-key role-based access architecture maps directly to the DPP stakeholder model: master key (Proud Tek encoder), application key 1 (consumer-readable public file), key 2 (brand-owner-only file), key 3 (service-provider repair-history file), key 4 (recycler end-of-life file). Each stakeholder reads only the files their role authorises. The chip carries the GS1 Digital Link 1.3 + ISO/IEC 15459 unique identifier per the EU ESPR 2024/1781 framework.

## Machine Routes
- JSON: https://proudtek.com/machine/products/rfid-labels/ntag424-dna-tamper-evident-tag.json
- Text: https://proudtek.com/machine/products/rfid-labels/ntag424-dna-tamper-evident-tag.txt