SMS API frequently asked questions

• How can replies be received through the API?
• How can replies be matched to the sent message?
• How will the sending number be displayed?
• Can outbound messages sent through the API come from one number?
• How can multiple messages be sent through the API?
• What is the character limit on an SMS message?
• How does the API communicate with the SMS gateways?
• Can messages be encrypted?
• How does delivery tracking work?
• Can line breaks be added to SMS messages?
• Is sample code provided?

How can replies be received through the API?

There are two methods for receiving SMS replies back to the API:

1. Polling the SMS gateway
Replies will be stored on the SMS gateway until a request from the API polls for the messages. Messages can then be downloaded to the API and handled by your application.
2. Pushing messages
Alternatively, messages can be pushed to your application through HTTP GET variables immediately after being received by the SMS gateway.

How can replies be matched to the sent message?

Messages sent through messagemedia's fully featured APIs can be tagged with an internal message ID. This ID will then be attached to any corresponding replies, allowing your system to easily match the reply to the originating messages.

How will the sending number be displayed?

As part of messagemedia's infrastructure, messages sent through the API will appear to come from a range of random numbers. The range of numbers are used as part of the process of matching replies to the relevant message.

This means that a recipient may see a different sending number for most messages received from the API. However, recipients only need to reply to the message and their reply will be delivered back to the correct sender.

For an inbound service (receiving messages originated by a handset) a dedicated number must be allocated to your account.

Can outbound messages sent through the API come from one number?

Yes, messagemedia can provide API customers with a dedicated number that will display all messages as being received from the same number. Please contact messagemedia for more details on setting up a dedicated number service.

A dedicated number will also allow you to operate an inbound service, ie receiving messages originated from a handset.

How can messages be sent to multiple numbers through the API?

All of messagemedia's APIs can send messages to multiple numbers, by adding phone numbers and messages to the API's internal message batch. These messages can then be sent out to all the recipients in one batch.

What is the character limit on an SMS message?

SMS messages are limited to a maximum of 160 characters. However, messagemedia's APIs have the ability to split any messages over 160 characters into multiple messages. These messages include a reference that the message is continued, and messages are sent to the recipients at intervals of 30 seconds.

How does the API communicate with the SMS gateways?

The API communicates with messagemedia's SMS gateway through HTTP on Port 80 (or port 443 for secure mode). Proxy servers and authentication can also be handled by the API. If your firewall requires that specific addresses be permitted access, please contact us.

Can messages be encrypted?

Yes, the secure mode in our SMS APIs allow messages to be sent using HTTPS over port 443.

How does delivery tracking work?

Delivery tracking technology can be used to record the exact time and date that messages are received on a recipient's handset. Delivery reports are sent to the API in the same manner as replies, but with no message text. The status of the delivery report will either be: P for pending, D for delivered or F for failed, indicating the status of the message. Messages will be marked as Pending until it is either marked as delivered or fails.

Can line breaks be added to SMS messages?

New lines can be created using your operating system's standard newline character, for example: \r\n.

Is sample code provided?

All APIs include sample code in the documentation or API package. Additional code examples in Visual C++, VB.NET and ASP are available for the COM API.