Key concepts

Initialization request

When a user initializes a captcha on the business client, the client sends a request to the captcha server for captcha JS resources, such as images or challenge questions (Step 1 in the sequence diagram).

Validation request

After a user completes a captcha challenge, such as dragging a slider or solving a puzzle, the business client sends a validation request to the captcha server. This request determines whether the interaction was from a human or a bot (Step 3 in interactive verification and Step 4.1(i) in frictionless verification). It can also be the initial check in frictionless verification mode (Step 3 in frictionless verification).

Verification request

The business server calls the VerifyIntelligentCaptcha API on the captcha server to validate the CaptchaVerifyParam parameter (Step 6 in the sequence diagram).

Identity prefix

A prefix for the captcha user identity. After you activate Captcha 2.0, you can find this value in the upper-right corner of the Overview page in the console. You pass it as a global parameter in your client-side integration code. The right side of the Product Overview page shows the identity prefix. The current version is Pay-As-You-Go. At the bottom of the page, there are options to purchase a subscription and purchase a resource plan. Click Details for more information.

Scene ID

A unique identifier generated after you create and save a new scene in the console. You pass it as an initialization parameter in your client-side code and it corresponds to specific configurations such as verification type, interaction style, and security policies. This allows you to manage different business scenarios separately. To find a scene ID, log on to the captcha service console, go to the scene management page, and look in the Scene Name/ID column of the scene list.

CertifyID

A unique identifier for a single request. Provide this ID to support for troubleshooting. In the "Please complete the verification" dialog box, you can find the CertifyId value in the lower-left corner (for example, CertifyId: Okxtt6wkkn). A slider captcha appears in the center of the dialog box with the prompt, "Drag the slider to the rightmost side."

Custom policy

Within the bot detection security framework, you can customize security policies in the console to fine-tune protection beyond the baseline security level. For more details, see custom policy.

V2 technical architecture

In the V2 technical architecture, the business server sends a validation request to the captcha server. The captcha server then returns the result to the business server for further processing. For more details, see the V2 verification architecture sequence diagram.

V2 architecture identification features

• The captchaVerifyCallback callback function handles CAPTCHA verification.

• The onBizResultCallback callback function handles the business result.

• The scene ID (SceneId) is passed in directly without encryption.

• The validation request is initiated by the business server, which calls the VerifyIntelligentCaptcha API.

V3 technical architecture

In the V3 technical architecture, the business client sends a validation request to the captcha server. If the validation fails, the captcha refreshes and continues to interact with the business client. The process proceeds to the subsequent business verification step only after the captcha is passed. For more details, see the V3 verification architecture sequence diagram.

V3 architecture identification features

• The client passes the scene ID (SceneId) parameter during initialization.

• The success callback function handles a successful verification, and the fail callback function handles a failed verification.

• Encryption is optional: use the ekey obtained from the console to encrypt the scene ID with AES-256-CBC, and pass in the resulting EncryptedSceneId.

• The validation request is initiated directly by the business client.