> For the complete documentation index, see [llms.txt](https://developer.magtek.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.magtek.com/products/dynafamily-mms-dyna-devices/dynaflex-ii-ped/security-and-keys.md).

# Security & Keys

How the DynaFlex II PED protects cardholder data and manages keys. These are\
shared DynaFamily concepts, documented in the <mark style="color:red;">**Guides Section**</mark>:

{% hint style="success" %}
Applies to: DynaFlex II PED
{% endhint %}

### Security & Key Guides

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Reference Section</strong></td><td><strong>Information Available</strong></td></tr><tr><td valign="middle"><mark style="color:red;"><strong>DUKPT: 3DES/TDEA --> AES Migration</strong></mark></td><td>How DUKPT derives a unique key per transaction, and the path (and reasons) for moving from legacy 3DES/TDEA DUKPT to AES DUKPT on your devices and host.</td></tr><tr><td valign="middle"><mark style="color:red;"><strong>Key Serial Numbers (KSN)</strong></mark></td><td>What a KSN is, how it's structured, and how it identifies the unique key used to encrypt a given transaction under DUKPT.</td></tr><tr><td valign="middle"><mark style="color:red;"><strong>Message Authentication Codes (MAC)</strong></mark></td><td>How a MAC lets the host and device confirm a message hasn't been altered in transit, and when one is required.</td></tr><tr><td valign="middle"><mark style="color:red;"><strong>Encryption &#x26; Decryption</strong></mark></td><td>How the reader encrypts data at the point of read (SRED), how to determine which key was used, and how to decrypt the output on your host.</td></tr><tr><td valign="middle"><mark style="color:red;"><strong>TR-31 Key Blocks</strong></mark></td><td>The ANSI TR-31 key-block format used to transport and load keys securely into the device.</td></tr><tr><td valign="middle"><mark style="color:red;"><strong>PCI requirements (24-hour Reset, device lock)</strong></mark> </td><td>The operational requirements the device enforces for PCI compliance: the 24-hour automatic reset and the device lock feature.</td></tr></tbody></table>

### Full Security & Key Guides Section

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Reference Section</strong></td><td><strong>Information Available</strong></td></tr><tr><td valign="middle"><a href="https://developer.magtek.com/guides"><mark style="color:red;"><strong>Security &#x26; Key Guides</strong></mark></a></td><td>This section covers how DynaFamily readers protect cardholder data and manage keys.</td></tr></tbody></table>

### For more help

{% hint style="info" %}
**Need Help?**

For additional support, please contact MagTek Support:

**Technical Support:**

* 📧 **Email:** <support@magtek.com>
* 📞 **Phone:** 1-800-788-6835 (US) | +1-562-546-6616 (International)
* 🕐 **Hours:** Monday-Friday, 6:00 AM - 5:00 PM PST

**Online Resources:**

* 🌐 **Official Site:** [https://www.magtek.com](https://www.magtek.com/)
* 💬 **Developer Forum:** [https://forum.magtek.com](https://forum.magtek.com/)

**Documentation Feedback:**

Help us improve this documentation! [Submit feedback](broken://spaces/1lWLescKFIPsMeIJI6Cd/pages/5314c528980689961380bea0044c1256aaeb39bc)
{% endhint %}


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