add liveness GA document

Author: Jinyu Li

articles/ai-services/computer-vision/sdk/understand-the-liveness-sdk-versions.md

@@ -0,0 +1,31 @@
+---
+title: Understand Liveness Client-side SDK versions 
+titleSuffix: Azure AI services
+description: Explains the importance of updating the Liveness SDK for security and reliability, detailing versioning and update policies
+author: JinyuID
+ms.author: lijiny
+manager: qingflin
+ms.service: azure-ai-vision
+ms.date: 01/15/2025
+---
+
+# Understand the Liveness Client-side SDK versions
+
+Microsoft will regularly upgrade the liveness detection client SDK and service to improve security, reliability, and user convenience. Staying current with these updates is crucial because the liveness detection field faces active and sophisticated attacks.
+
+## Client-side SDK Versions
+
+Liveness detection client-side SDK uses major.minor.patch format to indicate software version.   
+- A patch version update is optional reliability fix on client SDK, it won’t impact the compatibility with service.
+- A minor version update is important security and reliability improvement. We will try to extend support for  a minor update as long as possible, Azure service might announce retirement of minor update after 6 months
+- A major version update is critical security or breaking API updates. Customers should make client update as soon as possible. Azure service will block the previous major version after 6 months.    
+
+## Azure Face API Service Version
+
+Face liveness detection feature is generally available from version 1.2. Face API will follow the Azure developing cycle, newer API version will add new features in preview release, then general available. A newer service version may require a newer minimal client SDK version. The requirement will be announced when new service version is available.
+
+## Service Model Version
+
+In the Create Liveness Session operation, customers can specify a liveness model version to classify the session. Azure service is also progressively updating  new models. We strongly recommend customers always use the latest model version, which means simply leaving the model version parameter empty.
+- The latest model version (default version) will be compatible with all supported client versions. 
+- When a service model is to be retired, Azure service will announce this 6 months ahead, providing customers with buffer time to update their backend service.

articles/ai-services/computer-vision/toc.yml

@@ -355,6 +355,8 @@ items:
       href: /legal/cognitive-services/face/data-privacy-security?context=/azure/ai-services/computer-vision/context/context
     - name: Limited Access features
       href: /legal/cognitive-services/computer-vision/limited-access-identity?context=/azure/ai-services/computer-vision/context/context
+    - name: Shared Responsibility for Face Liveness Detection
+      href: /legal/cognitive-services/face/shared-responsibility-for-liveness-detection?context=/azure/ai-services/computer-vision/context/context
 
   - name: Reference
     items:
@@ -380,6 +382,8 @@ items:
         href: https://aka.ms/azure-ai-vision-face-liveness-client-sdk-ios-api-reference
       - name: JavaScript (Web)
         href: https://aka.ms/azure-ai-vision-face-liveness-client-sdk-web-api-reference
+      - name: the Liveness SDK versions
+        href: sdk/understand-the-liveness-sdk-versions.md
 - name: Video Analysis
   items:
   - name: Video Analysis overview