# Subscribing users via Scienlabs

When one of your users clicks your marketing banner/material, you must generate the user a unique **trxID**, this is per user, per session. 

<table><thead><tr><th width="196">Parameter</th><th>Example</th><th>Description</th></tr></thead><tbody><tr><td>trxID</td><td>5cf60043-a8bb-4571-925e-57688e05fe36</td><td>A unique transaction reference.</td></tr></tbody></table>

{% hint style="info" %}
**Please note:** You cannot present the user with a page while you do this, it must be completely invisible to the user.
{% endhint %}

Once you have generated the unique **trxID**, you then must redirect the user to an url Mobivate will provide you with. For example:&#x20;

#### <mark style="color:green;">`REDIRECT`</mark> `https://content.mobivate.com/lookup/ke/return?<your_url_encoded_url>&service=<mobivate_keyword>&reference=<trxID>`

With the Scienlabs fraud-prevention, you must include two additional fields along with your trxID.&#x20;

<table><thead><tr><th width="196">Parameter</th><th>Example</th><th>Description</th></tr></thead><tbody><tr><td>return</td><td>https%3A%2F%2Fapp.mycontent.com</td><td>The url you wish to redirect users to upon successful subscription. This must be <a href="https://www.urlencoder.org/">URL encoded</a>.</td></tr><tr><td>service</td><td>MV-1000000000012</td><td>Your unique Mobivate keyword. Your account manager can provide you with this.</td></tr><tr><td>reference</td><td>5cf60043-a8bb-4571-925e-57688e05fe36</td><td>A unique transaction reference. Please see above.</td></tr></tbody></table>

{% hint style="warning" %}
**Please note:** You must append the **trxID** to the URL Mobivate provide you with.
{% endhint %}

To read more about how to configure your subscription notifications, please read our [Campaign Configuration guide](https://wiki.mobivate.com/mno-web-opt-in/configuring-your-campaign#receive-callback-notifications-to-your-own-endpoint).&#x20;