Post Syndicated from Tyler Holmes original https://aws.amazon.com/blogs/messaging-and-targeting/how-to-implement-self-managed-opt-outs-for-sms-with-amazon-pinpoint/

Amazon Pinpoint offers marketers and developers the ability to send SMS to over 240 countries and/or regions around the world; giving users the global reach, scalability, cost effective pricing, and high deliverability that is required to build a successful SMS program. SMS is a flexible communication channel that facilitates different business requirements, including One-Time Password (OTP), reminders, and bulk marketing to name a few. Regardless of the content that you are sending via SMS there is a requirement to manage your recipients’ opt-in/out status. Read on to learn your two options for managing opt-outs and how you can configure them. Amazon Pinpoint offers a fully managed opt-out capability and the ability to self-manage the process with your own tools.

NOTE: If you are sending to US numbers with a toll-free (TFN) number the carriers will automatically manage those numbers and are not eligible for either of these processes.

Managed Opt-Out Process
If you prefer to have Pinpoint manage your opt-out processes you can refer to our blog “How to Manage SMS Opt-Outs with Amazon Pinpoint” to learn how to configure keywords and opt-out lists.

Self-Managed Opt-Out Process
Many customers use Pinpoint’s Managed Opt-Out process to deliver their communications, but some scenarios require the ability to self-manage this process. Self-managing the opt-out process provides more granular control over customer communication preferences and allows customers to centralize those preferences within their own applications.
Common reasons for organizations to implement self-managed opt-out include but aren’t limited to:

1. Have an existing self-managed opt-out capability with a standing toolset that is already integrated with other aspects of their communication stack.
2. Need multiple options for their customers to manage the communication preferences such as a web portal, call center, and mobile application to name a few.
3. Require full control in order to implement custom logic that caters to their business needs.
4. Want to change their SMS provider to Pinpoint while not changing what they have already built within an existing application.

How to implement Self-Managed Opt-Outs with Pinpoint
Choosing to self-manage your opt-outs requires some configuration within Pinpoint and the use of other AWS services. The solution outlined in this blog will use Amazon Pinpoint in addition to the following services:

1. AWS Lambda
2. Amazon DynamoDB
3. Amazon SNS

NOTE: If you have existing services/applications that allow you to implement similar functionality as explained in this blog, you don’t have to use these services listed above.

What’s in scope?

This blog covers the following scenario:

1. SMS is being sent with Amazon Pinpoint SMS and Voice V2 API – SendTextMessage
2. You specify the Origination Identity (OID) to be used (short code, long code, 10DLC, etc) as the parameter to send the SMS to the destination phone number.

While the following scenarios can be self-managed this blog does not cover the following cases:

1. You use a phone-pool to send SMS.
2. You do not specify an OID in your call SendTextMessage call and let Amazon Pinpoint figure out and use the appropriate OID.

Keywords in scope

1. Opt-out keywords – All Opt-out keywords mentioned in this document are included in the code.
2. Opt-in keywords – This blog considers ‘JOIN’ as a valid keyword that SMS recipients can respond with to opt back in for the SMS communication.

NOTE: The code examples in this blog can be modified to add any additional custom keywords for your use case.

Assumptions/Prerequisites

1. You have the necessary permissions to configure the following services in the same AWS account and region where Amazon Pinpoint is implemented.
   a. AWS Lambda
   b. Amazon DynamoDB
   c. Amazon SNS
2. Your instance of Amazon Pinpoint has at least one OID approved and provisioned to send SMS.
   a. If you need help to determine what OID fits your use case(s) use this guide
   b. NOTE: Sender IDs do not have an ability to receive 2-way communication. If you are using Sender IDs, you still must manage opt-outs, but must do so by offering alternative ways of opting out such as a web portal, call center, and/or mobile applications.

Solution Overview

The solution proposed in this blog is fully serverless arhitecture and uses AWS managed services to eliminate a need for you to maintain and manage any of the infrastructure components.

1. Your application invokes AWS Lambda function ‘InvokeSendTextMessage’ which calls Amazon Pinpoint SMS and Voice V2 API – SendTextMessage.
2. The AWS Lambda function called ‘InvokeSendTextMessage’ performs the following tasks:
   2a. Fetches the latest item based on the descending order of the timestamp with the destination phone number and OID from Amazon DynamoDB table ‘SMSOptOut‘.
   2b. If an item is found with the customer response as any valid keyword for Opt-out (Refer section Keywords in scope), the process stops and Amazon Pinpoint APIs won’t be called by InvokeSendTextMessage function as the customer chose to opt-out.
   2c. If an item is not found or is found with the customer response as any valid keyword for Opt-in (Refer section Keywords in scope), the function calls Amazon Pinpoint SMS and Voice V2 API – SendTextMessage to deliver it to the customer/destination phone number.

NOTE: Amazon DynamoDB table can also be configured to receive the Opt-out or Opt-in information through various other channels (app, website, customer care etc.) if you have multiple interfaces for customer to do so but that is not in the scope for this blog.

Refer to the section, ‘InvokeSendTextMessage function code’ to understand the sample AWS Lambda function code. The code uses Python 3.12 language.

3. The message is successfully delivered to a destination phone number.
4. If the customers responds to the same OID (because you have enabled 2-way SMS feature) with a keyword that is a valid value from all the keywords in scope (Refer section Keywords in scope), Amazon SNS topic is configured with Amazon Pinpoint which captures the customer response.
   Note: The other keywords are not in scope for this blog, but you can specifically add all possible keywords that customers can respond with. There can be an accidental responses by a customer which will be ignored by the AWS Lambda code.
5. AWS Lambda function ‘AddOptOutInDynamoDB’ is a subscriber to the topic in Amazon SNS and processes customer responses.

6. AWS Lambda function ‘AddOptOutInDynamoDB’ performs few tasks as described below
7. 6a. If the customer response is a keyword that is a valid value from all the keywords in scope (Refer section Keywords in scope), Amazon Lambda function ‘AddOptOutInDynamoDB‘ extracts the OID and customer phone number information from the response and adds the entry in the Amazon DynamoDB table ‘SMSOptOut’. This way Amazon DynamoDB table keeps getting latest customer opt-in/opt-out status.
   6b. Once the item is successfully put in dynamodb table ‘SMSOptOut‘, if the customer response was any Opt-out keyword (Refer section Keywords in scope), the function sends a SMS to the customer who has just opted out to confirm the status. “YOU HAVE BEEN UNSUBSCRIBED. IF THIS WAS A MISTAKE PLEASE TEXT “JOIN” TO THIS NUMBER TO BE RESUBSCRIBED”.
   If the customer response was any Opt-in keyword (Refer section Keywords in scope) the function sends a SMS to the customer who has just opted back in to confirm the status. “YOU HAVE BEEN SUBSCRIBED. IF THIS WAS A MISTAKE PLEASE TEXT “STOP” OR “UNSUBSCRIBE” TO THIS NUMBER TO BE UNSUBSCRIBED”. (But SMS recipients can still respond with any valid keyword mentioned in Opt-out keyword list)

NOTE: Refer the section ‘AddOptOutInDynamoDB function code’ to understand the sample code. The code uses Python3.12 language.

7. The Opt-in/Opt-out status confirmation SMS is successfully delivered to a customer/destination phone number.

Amazon Pinpoint setup

1. Enable 2-way SMS messaging for the OID that you procured. Refer to the screenshot below for your reference.

2-way SMS setting:

2. Enable the self-managed opt-out feature for the OID. Once enabled, Amazon Pinpoint does not respond to opt-out messages sent to the SNS topic by your recipients. You can collect the response from the customers in an AWS SNS topic and process it as per your business needs.

Self Managed Opt-Out feature setting:

Amazon SNS setup

1. On Amazon SNS console, click on ‘Topics’ and then ‘create a topic’ as shown below.

2. Click ‘Create Subscription‘ to add the Lambda function ‘AddOptOutInDynamoDB‘ as a subscriber by using the Amazon Resource Name (ARN).

Amazon DynamoDB Setup

Table Name: ‘SMSOptOut‘

The Customer phone number is used as the primary key(PK). The sort key(SK) contains multiple values that include OID, timestamp, and the customer response separated by #. By having generic attribute names as PK and SK, you can expand the usage of this table for accommodating any custom business needs. For example: Customer can use any of the individual phone numbers like short code, long code, or 10DLC to send the SMS and any of these values can be accomodated as a part of the sort key (SK). The sort key can be used for granular retrieval to see the latest customer status (For example: ‘STOP‘). It can then additionally have attributes like OID, Timestamp, Response and others as per your requirements. The table uses On-demand Read/Write capacity mode. Refer to this document to understand On-demand capacity mode in detail.

Sample item in DynamoDB table is below

InvokeSendTextMessage function code

This AWS Lambda function calls Amazon Pinpoint SMS and Voice V2 API – SendTextMessage. It uses Query API for DynamoDB to scan the items for SourcePhoneNumber (customer phone number) and OID (Part of SK) in descending order of the timestamp. If an item exists with customer response value is a valid keyword for Opt-out (Refer section Keywords in scope), it means the customer has opted-out and the SMS can’t be sent. If no item is found or the customer response value is a valid keyword for Opt-in (Refer section Keywords in scope), the customer can be contacted and the funtion calls SendTextMessage API with the same OID and customer phone number.

import boto3
import os
from boto3.dynamodb.conditions import Key, Attr
import json

dynamodb = boto3.resource('dynamodb')
table = dynamodb.Table('SMSOptOut')
pinpoint = boto3.client('pinpoint-sms-voice-v2')
OptOutKeyword = ['ARRET','CANCEL','END','OPT-OUT','OPTOUT','QUIT','REMOVE','STOP','TD','UNSUBSCRIBE']
OptInKeyword = ['JOIN']

#adds item in the DynamoDB table
def query_table(OID, SourcePhoneNumber):
    try:
        response = table.query(
            KeyConditionExpression=Key('PK').eq(SourcePhoneNumber) & Key('SK').begins_with(OID),
            ScanIndexForward=False,
            Limit=1
        )
    except Exception as e: 
        print("Error when writing an item in DynamoDB table: ",e) 
        raise e
    return response

#send opt-in/opt-out confirmation text using send_text_message.
def send_confirmation_text(SourcePhoneNumber,OID,messageBody,messageType): 
    
    try: 
        response = pinpoint.send_text_message(DestinationPhoneNumber=SourcePhoneNumber, 
        OriginationIdentity=OID,
        MessageBody=messageBody, 
        MessageType=messageType 
        ) 
    except Exception as e: 
        print("Error in sending text message using Pinpoint send_text_message api:", e) 
        raise e

#gets the message from SNS topic
def lambda_handler(event, context):
    OID = event['OID']
    SourcePhoneNumber = event['SourcePhoneNumber']

    response=query_table(OID, SourcePhoneNumber)
    items = response['Items']
    
    #Count number of items. The value will be either 1 or 0.
    count = len(items)

    # If the latest customer response is any OptOutKeyword
    if count == 1 and items[0]['Response'] in OptOutKeyword:
        print("Exit : Customer has opted out, do not send SMS")
    # If the latest customer response is any OptOutKeyword
    elif count == 0 or (count == 1 and items[0]['Response'] in OptInKeyword):
        send_confirmation_text(SourcePhoneNumber,OID,'This is a test message from Amazon Pinpoint','TRANSACTIONAL')
    # Only allowed values for customer response are valid OptOutKeyword or OptInKeyword 
    else: 
        print("The customer response is not one of the allowed keyword")

AddOptOutInDynamoDB Lambda function code

For example: When customer responds with ‘STOP’, the response is captured in the SNS topic that you configured with Amazon Pinpoint. The response json looks as shown below –

{
"originationNumber": "+1224xxxxxxx",
"destinationNumber": "+1844xxxxxxx",
"messageKeyword": "KEYWORD_xxxxxxxxxxxx",
"messageBody": "STOP",
"previousPublishedMessageId": "xxxxxxxxxxxxxx",
"inboundMessageId": "xxxxxxxxxxxxxx"
}

This Lambda function extracts the OID (destinationNumber), Customer phone number (originationNumber), and the customer response (messageBody) from the json payload above and adds an entry in the DynamoDB table (SMSOptOut). Once the item is put successfully in DynamoDB table, the function also sends out a confirmation SMS (either Opt-in or Opt-out) to the customer phone number using SendTextMessage.
For example:

• If the customer response value is a valid keyword for Opt-out (Refer section Keywords in scope), the confirmation SMS is ‘YOU HAVE BEEN UNSUBSCRIBED. IF THIS WAS A MISTAKE PLEASE TEXT “JOIN” TO THIS NUMBER TO BE RESUBSCRIBED’.
• If the customer response value is a valid keyword for Opt-in (Refer section Keywords in scope), the confirmation SMS is ‘YOU HAVE BEEN SUBSCRIBED. IF THIS WAS A MISTAKE PLEASE TEXT “STOP” OR “UNSUBSCRIBE” TO THIS NUMBER TO BE UNSUBSCRIBED’.

import json
import boto3
import datetime

dynamodb = boto3.resource('dynamodb')
dynamodb_table = dynamodb.Table('SMSOptOut')
pinpoint = boto3.client('pinpoint-sms-voice-v2')
OptOutKeyword = ['ARRET','CANCEL','END','OPT-OUT','OPTOUT','QUIT','REMOVE','STOP','TD','UNSUBSCRIBE']
OptInKeyword = ['JOIN']

#adds item in the DynamoDB table
def put_item(data,current_timestamp):
    print(dynamodb_table)
    try:
        response = dynamodb_table.put_item(
            Item = {
                'PK': data['originationNumber'],
                'SK': data['destinationNumber']+'#'+current_timestamp+'#'+data['messageBody'], 
                'OID': data['destinationNumber'],
                'Timestamp': current_timestamp,
                'Response': data['messageBody']
            }
        )
    except Exception as e:
        print("Error when writing an item in DynamoDB table: ",e)
        raise e

#send opt-in/opt-out confirmation text using send_text_message.
def send_confirmation_text(data,messageBody,messageType):
    try:
        response = pinpoint.send_text_message(
            DestinationPhoneNumber=data['originationNumber'],
            OriginationIdentity=data['destinationNumber'],
            MessageBody=messageBody,
            MessageType=messageType
            )
    except Exception as e:
        print("Error in sending text message using Pinpoint send_text_message api:", e)
        raise e
        
#gets the message from SNS topic
def lambda_handler(event, context):
    message = event['Records'][0]['Sns']['Message']
    data = json.loads(message)
    current_timestamp = datetime.datetime.now().isoformat()

    if data['messageBody'] in OptOutKeyword:
        put_item(data,current_timestamp)
        send_confirmation_text(data, 'YOU HAVE BEEN UNSUBSCRIBED. IF THIS WAS A MISTAKE PLEASE TEXT "JOIN" TO THIS NUMBER TO BE RESUBSCRIBED', 'TRANSACTIONAL')
    elif data['messageBody'] in OptInKeyword:
        put_item(data,current_timestamp)
        send_confirmation_text(data, 'YOU HAVE BEEN SUBSCRIBED. IF THIS WAS A MISTAKE PLEASE TEXT "STOP" OR "UNSUBSCRIBE" TO THIS NUMBER TO BE UNSUBSCRIBED', 'TRANSACTIONAL')
    else:
        print("The customer response is not one of the allowed keyword")

Clean Up

DynamoDB storage and any Lambda invocation will incur a cost so it is important to delete these resources if you do not plan on using them as shown below.

DynamoDB:

1. 1. On DynamoDB table, select table ‘SMSOptOut’ and click Delete. Confirm the action.

Lambda:

1. On Lambda console, find the 2 functions you created and click Actions → Delete. Confirm the actions.

Amazon Pinpoint

1. After deleting the DynamoDB table and Lambda functions your self-managed Opt-out flow will not work so you will need to disable self-managed opt-outs in Pinpoint for the respective OID as shown below.

Conclusion
In this post, you learned how to implement a self-managed opt-out workflow when using Pinpoint SMS. Keep in mind that when you implement the self-managed Opt-out flow, Pinpoint will not track or maintain any opt-out status for the OID that it was enabled for.

Take the time to plan out your approach, follow the steps outlined in this blog, and take advantage of any resources available to you within your support tier.

Decide what origination IDs you will need here
Review the documentation for the V2 SMS and Voice API here
Check out the support tiers comparison here

Resources:
https://docs.aws.amazon.com/sms-voice/latest/userguide/phone-numbers-sms-by-country.html
https://aws.amazon.com/blogs/messaging-and-targeting/how-to-utilise-amazon-pinpoint-to-retry-unsuccessful-sms-delivery/
https://docs.aws.amazon.com/pinpoint/latest/userguide/channels-sms-limitations-opt-out.html
https://docs.aws.amazon.com/pinpoint/latest/userguide/channels-sms-simulator.html
https://docs.aws.amazon.com/dynamodb/
https://docs.aws.amazon.com/sns/
https://docs.aws.amazon.com/lambda/

Post Syndicated from Tyler Holmes original https://aws.amazon.com/blogs/messaging-and-targeting/how-to-send-sms-using-a-sender-id-with-amazon-pinpoint/

Amazon Pinpoint enables you to send text messages (SMS) to recipients in over 240 regions and countries around the world. Pinpoint supports all types of origination identities including Long Codes, 10DLC (US only), Toll-Free (US only), Short Codes, and Sender IDs.
NOTE: Certain subtypes of Origination Identities (OIDs), such as Free to End User (FTEU) Short Codes might not be supported

Unlike other origination identities, a Sender ID can include letters, enabling your recipients to receive SMS from “EXAMPLECO” rather than a random string of numbers or phone number. A Sender ID can help to create trust and brand awareness with your recipients which can increase your deliverability and conversion rates by improving customer interaction with your messages. In this blog we will discuss countries that allow the use of Sender IDs, the types of Sender IDs that Pinpoint supports, how to configure Pinpoint to use a Sender ID, and best practices for sending SMS with a Sender ID. Refer to this blog post for guidance planning a multi-country rollout of SMS.

What is a Sender ID?

A sender ID is an alphanumeric name that identifies the sender of an SMS message. When you send an SMS message using a sender ID, and the recipient is in an area where sender ID is supported, your sender ID appears on the recipient’s device instead of a phone number, for example, they will see AMAZON instead of a phone number such as “1-206-555-1234”. Sender IDs support a default throughput of 10 messages per second (MPS), which can be raised in certain situations. This MPS is calculated at the country level. As an example, a customer can send 10 MPS with “SENDERX” to Australia (AU) and 10 MPS with “SENDERX” to Germany (DE).

The first step in deciding whether to use a Sender ID is finding out whether the use of a Sender ID is supported by the country(ies) you want to send to. This table lists all of the destinations that Pinpoint can send SMS to and the Origination Identities that they support. Many countries support multiple origination identities so it’s important to know the differences between them. The two main considerations when deciding what originator to use is throughput and whether it can support a two-way use case.

Amazon Pinpoint supports three types of Sender IDs detailed below. Your selection is dependent on the destination country for your messages, consult this table that lists all of the destinations that Pinpoint can send SMS to.

Dynamic Sender ID – A dynamic sender ID allows you to select a 3-11 character alphanumeric string to use as your originator when sending SMS. We suggest using something short that outlines your brand and use case like “[Company]OTP.” Dynamic sender IDs vary slightly by country and we recommended senders review the specific requirements for the countries they plan to send to. Pay special attention to any notes in the registration section. If the country(ies) you want to send to require registration, read on to the next type of Sender ID.

Registered Sender ID – A registered SenderID generally follows the same formatting requirements as a Dynamic Sender ID, alowing you to select a 3-11 character alphanumeric string to use, but has the added step of completing a registration specific to the country you want to use a Sender ID for. Each country will require slightly different information to register, may require specific forms, as well as a potential registration fee. Use this list of supported countries to see what countries support Sender ID as well as which ones require registration.

Generic, or “Shared” Sender ID – In countries where it is supported, when you do not specify a dynamic Sender ID, or you have not set a Default Sender ID in Pinpoint, the service may allow traffic over a Generic or Shared SenderID like NOTICE. Depending on the country, traffic could also be delivered using a service or carrier specific long or short code. When using the shared route your messages will be delivered alongside others also sending in this manner.

As mentioned, Sender IDs support 10 MPS, so if you do not need higher throughput than this may be a good option. However, one of the key differences of using a Sender ID to send SMS is that they do not support two-way use cases, meaning they cannot receive SMS back from your recipients.

IMPORTANT: If you use a sender ID you must provide your recipients with alternative ways to opt-out of your communications as they cannot text back any of the standard opt-out keywords or any custom opt-in keywords you may have configured. Common ways to offer your recipients an alternative way of opting out or changing their communication preferences include web forms or an app preference center.

How to Configure a Sender ID

The country(ies) you plan on sending to using a Sender ID will determine the configuration you will need to complete to be able to use them. We will walk through the configuration of each of the three types of Sender IDs below.

Step 1 – Request a Sender ID(Dependent on Country, Consult this List)

Some countries require a registration process. Each process, dependent on the country can be unique so it is required that a case be opened to complete this process. The countries requiring Sender ID registration are noted in the following list.
When you request a Sender ID, we provide you with an estimate of how long the request will take to complete. This estimate is based on the completion times that we’ve seen from other customers.

NOTE: This time is not an SLA. It is recommended that you check the case regularly and make sure that nothing else is required to complete your registration. If your registration requires edits it will extend this process each time it requires edits. If your registration passes over the estimated time it is recommended that you reply to the case.

Because each country has its own process, completion times for registration vary by destination country. For example, Sender ID registration in India can be completed in one week or less, whereas it can take six weeks or more in Vietnam. These requests can’t be expedited, because they involve the carriers themselves making changes to the ways that their networks are configured and certify the use case onto their network. We suggest that you start your registration process early so that you can start sending messages as soon as you launch your product or service.

IMPORTANT: Make sure that you are checking on your case often as support may need more details to complete your registration and any delay extends the expected timeline for procuring your Sender ID

Generic Sender ID – In countries that support a Generic or Shared ID like NOTICE there is no requirement to register or configure prior to sending we will review how to send with this type of Sender ID in Step 2.

Dynamic Sender ID – A Dynamic Sender ID can be requested via the API or in the console, complete the following steps to configure these Sender IDs in the console.
NOTE: If you are using the API to send it is not required that you request a Sender ID for every country that you intend on sending to. However, it is recommended, because the request process will alert you to any Sender IDs that require registration so you do not attempt to send to countries that you cannot deliver successfully to. All countries requiring registration for Sender IDs can be found here.

1. Navigate to the SMS Console
   1. Make sure you are in the region you plan on using to send SMS out of as each region needs to be configured independently and any registrations also need to be made in the account and region in which you will be sending from
2. Select “Sender IDs” from the left rail
   1. Click on “Request Originator”
      
   2. Choose a country from the drop down that supports Sender ID
   3. Choose “SMS”
      1. Leave “Voice” unchecked if it is an option.
         NOTE: If you choose Voice than you will not be able to select a Sender ID in the next step
      2. Select your estimated SMS volume
      3. Choose whether your company is local or international in relation to the country you are wanting to configure. Some countries, like India, require proof of residency to access local pricing so select accordingly.
      4. Select “No” for two-way messaging or you will not be able to select a Sender ID in the next step
   4. Click next and choose “Sender ID” and provide your preferred Sender ID.
      NOTE: Refer to the following criteria when selecting your Sender ID for configuration (some countries may override these)
      1. Numeric-only Sender IDs are not supported
      2. No special characters except for dashes ( – )
      3. No spaces
      4. Valid characters: a-z, A-Z, 0-9
      5. Minimum of 3 characters
      6. Maximum of 11 characters. NOTE: India is exactly 6 Characters
      7. Must match your company branding and SMS service or use case.
         1. For example, you wouldn’t be able to choose “OTP” or “2FA” even though you might be using SMS for that type of a use case. You could however use “ANYCO-OTP” if your company name was “Any Co.” since it complies with all above criteria.

NOTE: If the console instructs you to open a case as seen below than your Sender ID likely requires some form of registration. Read on to configure a Registered Sender ID.

Registered Sender ID – A registered sender ID follows the same criteria above for a Dynamic Sender ID, although some countries may have minor criteria changes or formatting restrictions. Follow the directions here to complete this process, AWS support will provide the correct forms needed for the country that you are registering. Each Registered Sender ID will need a separate case per country. Follow the link to the “AWS Support Center” and follow these instructions when creating your case

Step 2 – How to Send SMS with a Sender ID

Sender IDs can be used via three different mechanisms

Option 1 – Using the V2 SMS and Voice API and “SendTextMessage“
This is the preferred method of sending and this set of APIs is where all new functionality will be built on.

1. SendTextMessage has many options for configurability but the only required parameters are the following:
   1. DestinationPhoneNumber
   2. MessageBody
      
2. “OriginationIdentity” is optional, but it’s important to know what the outcome is dependent on how you use this parameter:
   1. Explicitly stating your SenderId
      1. Use this option if you want to ONLY send with a Sender ID. Setting this has the effect of only sending to recipients in countries that accept SenderIDs and rejecting any recipients whose country does not support Sender IDs. The US for example cannot be sent to with a Sender ID
   2. Explicitly stating your SenderIdArn
      1. Same effect as “SenderID” above
   3. Leaving OriginationIdentity Blank
      1. If left blank Pinpoint will select the right originator based on what you have available in your account in order of decreasing throughput, from a Short Code, 10DLC (US Only), Long Code, Sender ID, or Toll-Free (US Only), depending on what you have available.
         1. Keep in mind that sending this way opens you up to sending to countries you may not have originators for. If you would like to make sure that you are only sending to countries that you have originators for then you need to use Pools.
   4. Explicitly stating a PoolId
      1. A pool is a collection of Origination Identities that can include both phone numbers and Sender IDs. Use this option if you are sending to multiple country codes and want to make sure that you send to them with the originator that their respective country supports.
         1. NOTE: There are various configurations that can be set on a pool. Refer to the documentation here
            1. Make sure to pay particular attention to “Shared Routes” because in some countries, Amazon Pinpoint SMS maintains a pool of shared origination identities. When you activate shared routes, Amazon Pinpoint SMS makes an effort to deliver your message using one of the shared identities. The origination identity could be a sender ID, long code, or short code and could vary within each country. Turn this feature off if you ONLY want to send to countries for which you have an originator.
            2. Make sure to read this blogpost on Pools and Opt – Outs here
   5. Explicitly stating a PoolArn
      1. Same effect as “PoolId” above

Option 2 – Using a journey or a Campaign

1. If you do not select an “Origination Phone Number” or a Sender ID Pinpoint will select the correct originator based on the country code being attempted to send to and the originators available in your account.
   1. Pinpoint will attempt to send, in order of decreasing throughput, from a Short Code, 10DLC (US Only), Long Code, Sender ID, or Toll-Free (US Only), depending on what you have available. For example, if you want to send from a Sender ID to Germany (DE), but you have a Short Code configured for Germany (DE) as well, the default function is for Pinpoint to send from that Short Code. If you want to override this functionality you must specify a Sender ID to send from.
      1. NOTE: If you are sending to India on local routes you must fill out the “Entity ID and Template ID that you received when you registered your template with the Telecom Regulatory Authority of India (TRAI)
   2. You can set a default Sender ID for your Project in the SMS settings as seen below.
      NOTE: Anything you configure at the Campaign or Journey level overrides this project level setting
      

Option 3 – Using Messages in the Pinpoint API

1. Using “Messages“ is the second option for sending via the API. This action allows for multi-channel(SMS, email, push, etc) bulkified sending but is not recommended to standardize on for SMS sending.
   1. NOTE: Using the V2 SMS and Voice API and “SendTextMessage” detailed in Option 1 above is the preferred method of sending SMS via the API and is where new features and functionality will be released. It is recommended that you migrate SMS sending to this set of APIs.

Conclusion:
In this post you learned about Sender IDs and how they can be used in your SMS program. A Sender ID can be a great option for getting your SMS program up and running quickly since they can be free, many countries do not require registration, and you can use the same Sender ID for lots of different countries, which can improve your branding and engagement. Keep in mind that one of the big differences in using a Sender ID vs. a short code or long code is that they don’t support 2-way communication. Common ways to offer your recipients an alternative way of opting out or changing their communication preferences include web forms or an app preference center.

A few resources to help you plan for your SMS program:
Use this spreadsheet to plan for the countries you need to send to Global SMS Planning Sheet
The V2 API for SMS and Voice has many more useful actions not possible with the V1 API so we encourage you to explore how it can further help you simplify and automate your applications.
If you are needing to use pools to access the “shared pools” setting read this blog to review how to configure them
Confirm the origination IDs you will need here
Check out the support tiers comparison here