How do I use Amazon Cognito to configure an origination ID to send SMS messages?

Resolution

Specify the origination identity in Amazon Cognito

Use a Custom SMS sender AWS Lambda trigger in Amazon Cognito to customize the Amazon Simple Notification Service (Amazon SNS) Publish API. Then, configure values for the AWS.SNS.SMS.SenderID and AWS.MM.SMS.OriginationNumber attributes.

Use the AWS.MM.SMS.OriginationNumber and AWS.SNS.SMS.SenderID parameters to choose specific origination identities if a specific AWS Region has multiple origination numbers or sender IDs.

Default preferences for origination numbers

If the origination number isn't specified, then AWS uses the following preferences to send the SMS message:

• AWS checks whether it assigned a short code to the AWS account. If yes, then AWS uses the short code to send the message.
• When there's no short code, AWS selects the available long code associated with the account and the Region for that specific country. For the US, if there's no short code associated with the account, AWS selects 10DLC as a preference over the toll-free number.

Or, make sender ID the default in SNS-SMS text messaging preferences through the SNS text messaging console or the SNS SetSMSAttributesAPI. Amazon Cognito uses the configured default value of the sender ID as origination identity when sending SMS messages.