# AWS IP address ranges notifications
<a name="subscribe-notifications"></a>

AWS publishes its current IP address ranges in JSON format. Whenever there is a change to the AWS IP address ranges, we send notifications to subscribers of the Amazon SNS topic named `AmazonIpSpaceChanged`. For more information about the syntax of the JSON file, see [Syntax for AWS IP address range JSON](aws-ip-syntax.md).

The payload of the notification contains information in the following format.

```
{
  "create-time":"yyyy-mm-ddThh:mm:ss+00:00",
  "synctoken":"0123456789",
  "md5":"6a45316e8bc9463c9e926d5d37836d33",
  "url":"https://ip-ranges.amazonaws.com/ip-ranges.json"
}
```

**create-time**  
The creation date and time.  
Notifications could be delivered out of order. Therefore, we recommend that you check the timestamps to ensure the correct order.

**synctoken**  
The publication time, in Unix epoch time format.

**md5**  
The cryptographic hash value of the `ip-ranges.json` file. You can use this value to check whether the downloaded file is corrupted.

**url**  
The location of the `ip-ranges.json` file. For more information, see [Download the JSON file](aws-ip-ranges.md#aws-ip-download).

You can subscribe to receive notifications as follows.

**To subscribe to AWS IP address range notifications**

1. Open the Amazon SNS console at [https://console.aws.amazon.com/sns/v3/home](https://console.aws.amazon.com/sns/v3/home).

1. In the navigation bar, change the Region to **US East (N. Virginia)**, if necessary. You must select this Region because the SNS notifications that you are subscribing to were created in this Region.

1. In the navigation pane, choose **Subscriptions**.

1. Choose **Create subscription**.

1. In the **Create subscription** dialog box, do the following:

   1. For **Topic ARN**, copy the following Amazon Resource Name (ARN):

      ```
      arn:aws:sns:us-east-1:806199016981:AmazonIpSpaceChanged
      ```

   1. For **Protocol**, choose the protocol to use (for example, `Email`).

   1. For **Endpoint**, type the endpoint to receive the notification (for example, your email address).

   1. Choose **Create subscription**.

1. You'll be contacted on the endpoint that you specified and asked to confirm your subscription. For example, if you specified an email address, you'll receive an email message with the subject line `AWS Notification - Subscription Confirmation`. Follow the directions to confirm your subscription.

Notifications are subject to the availability of the endpoint. Therefore, you might want to check the JSON file periodically to ensure that you've got the latest ranges. For more information about Amazon SNS reliability, see [https://aws.amazon.com/sns/faqs/#Reliability](https://aws.amazon.com/sns/faqs/#Reliability).

If you no longer want to receive these notifications, use the following procedure to unsubscribe.

**To unsubscribe from AWS IP address ranges notifications**

1. Open the Amazon SNS console at [https://console.aws.amazon.com/sns/v3/home](https://console.aws.amazon.com/sns/v3/home).

1. In the navigation pane, choose **Subscriptions**.

1. Select the check box for the subscription.

1. Choose **Actions**, **Delete subscriptions**.

1. When prompted for confirmation, choose **Delete**.

For more information about Amazon SNS, see the *[Amazon Simple Notification Service Developer Guide](https://docs.aws.amazon.com/sns/latest/dg/)*.