> ## Documentation Index
> Fetch the complete documentation index at: https://docs.paybyrd.com/llms.txt
> Use this file to discover all available pages before exploring further.

# 3DS authentication

## What is 3D Secure (3DS)?

3D Secure (3DS) is an authentication protocol that adds a verification step to online card transactions. It requires cardholders to confirm their identity before a transaction is completed, reducing unauthorized card use.

## Why 3DS Matters

* **Fraud prevention:** Authenticates the cardholder, reducing unauthorized card use.
* **Chargeback protection:** Liability typically shifts to the card issuer for authenticated transactions.
* **Regulatory compliance:** Required for Strong Customer Authentication (SCA) under PSD2 in the EU and other regions.

## Challenges of Implementing 3DS

While 3DS provides many benefits, implementing it can be complex:

* Integration with card networks and issuers.
* Managing redirects for authentication.
* Handling variations across card brands and regions.
* Maintaining a seamless user experience.

## How Paybyrd handles 3DS

* A single API call enables 3DS in your payment flow. Paybyrd handles authentication and redirection automatically.
* The API response includes a 3DS action URL you can use to redirect the customer for authentication.
* Transaction status updates are delivered via webhooks — no polling required.
* Paybyrd supports SCA compliance for global and regional payment regulations.

## Integration options

Paybyrd offers two ways to integrate 3DS:

* [Simplified setup](/advanced/3ds-authentication/simplified-setup) — Paybyrd handles the full 3DS flow. Recommended for most integrations.
* [SDK setup](/advanced/3ds-authentication/sdk-setup) — Use Paybyrd's SDK for more control over the authentication flow.