Programmable Messaging
Sending and receiving SMS and MMS messages is simple using CarrierX's messaging API. This quick start will take you through all the steps necessary, from registering your brand and campaign, to account setup, getting a phone number, and the actual sending and receiving.
Registration
All messages sent using CarrierX's messaging API are considered Application-to-Person (A2P). To help combat spam and fraud, mobile carriers require that prior to sending any messages, you register and receive approval for your use case. Please see the registration page for a complete explanation and next steps.
SMS or MMS
CarrierX allows you to send two types of messages: SMS and MMS. In general, SMS is text only while MMS can include multimedia (audio, video, images) or other attachments.
While users do not really distinguish between SMS and MMS, and CarrierX treats them very similarly, there are important differences to understand.
SMS
SMS or short message service, is short text only messages sent to a single recipient. Although simple, SMS is appropriate for many use cases such as 2FA, delivery notifications, or Emergency alerts.
While SMS messages are limited to 160 characters or less, CarrierX will automatically break messages apart into what are called segments and deliver them as separate SMS messages.
In general, it is less expensive to send SMS than MMS messages. Each segment is billed as separately. So, depending on the length of the message, it may be less expensive to send a single MMS message than multiple SMS segments.
MMS
MMS or Multimedia Messaging Service is used to send messages containing images, audio and video, or to send to a group of recipients. Sending MMS is often used for marketing, news and entertainment, and political communications.
The size limit for MMS messages is much higher than SMS:
- text of up to 1,600 characters
- as many as 10 media files
- total size of up to 3 MB
MMS messages have a greater cost per message than SMS, but far greater potential. If you are sending to multiple recipients or what to include images or video, MMS is the format of choice.
This guide uses the term messaging to refer to both SMS and MMS except where distinguished. The CarrierX API largely abstracts away the difference, allowing you to simplify your code.
Types of Numbers
There are three types of numbers you can choose from to send and receive messages, each with its own messaging registration process. The three types are:
- Long Codes - regular 10-digit phone number.
- Toll-free - 8xx 10-digit numbers.
- Short Codes - 5 or 6-digit number.
The choice of number type has many trade-offs. Consider the following factors when choosing the number type for your messaging campaigns:
- Throughput - the number of messages per second, minute, hour.
- Cost - varies and applies to the campaign review and per message, and in the case of short codes, a monthly fee.
- Review Complexity - can vary based on message content as well as number type.
You will find information below that might help you choose the best solution for your needs.
Comparison of Number Types
| Number Type | Throughput | Cost | Review Complexity |
|---|---|---|---|
| Long Code | Varies based on content | Per message: lowest Brand: $4 - $95 Campaign: $2 - $30 / campaign / mo | Moderate brand review Per campaign reviews |
| Toll-Free | High | Per message: moderate Verification: $0 | Relatively simple |
| Short Code | Highest | Per message: highest Review: Highest Monthly cost | Highest. Reviewed by each mobile operator |