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License Change Notification (LCN)


License Change Notification (LCN) works as a message service generating automatic subscription notifications for your Avangate account. Use the notifications to process subscription data into your own management systems by synchronizing it with Avangate account events. Avangate generates notifications for subscription update and expiration events (including past due notifications).

How can I use LCN?

Use ICN to automate back-end functions for your services, including but not limited to:

  • Creating end user accounts
  • Providing access to acquired services
  • Manage subscriptions
  • Fulfilling purchases
  • Engaging subscribers
  • Converting trials to paid subscriptions
  • Cutting access to delinquent account

Webhook asynchronicity

Avangate’s webhooks (IPN and LCN) operate asynchronously

How does LCN work?

  1. Create one or multiple LCN listener pages on your website. Avangate sends LCNs to publicly accessible servers.
  2. Configure the LCN settings of your Avangate account to point to the URL of your default/preferred listener page.
  3. Set up additional Notification URLs if you require more listener pages, such as in testing scenarios in which you don’t want to use your default LCN listener. 
  4. Avangate sends subscription notifications to the endpoints you defined when subscribers change specific subscription details, using secure (HTTPS) POST.
  5. Avangate uses a HMAC_MD5 signature to validate the HTTPS POST.  Calculate the signature using data sent and your Avangate account’s secret key, following the instructions included in this article.
  6. Your custom LCN listener scripts consume the notifications and process the info received.
  7. Configure your LCN listener to output a read receipt confirmation in the listener page after receiving a valid LCN message.  This article includes guidance on how to generate the confirmation.
  8. In the absence of a confirmation from your LCN listener, Avangate continues to send notifications according to the failure retry process until you provide a valid response.
  9. The Avangate system regularly checks the status of subscriptions to identify expired items and modifications. Avangate then sends notifications for expirations as well as for updates occurred in the last 24 hours prior to the moment when it perform the check. Avangate does not re-send notifications for the same event unless the status of the subscription changes or it identifies additional modifications.

Set up the default LCN URL

  1. Login into your Avangate account.
  2. Navigate to LCN settings under System settings.
  3. Enter the URL corresponding to your default LCN listener in the LCN URL field.
  4. Save your settings.
  5. Avangate checks the validity of the URL in terms of access to ensure that notifications reach your LCN listener without issues.

Set up additional LCN URLs

Navigate to LCN settings under System settings, select the Notification URLs tab and click New URL configuration.

Secure your LCN script 

For security reasons, Avangate recommends that you restrict access to the LCN script.