SMS trunks#
SMS trunks connect your local, national, and mobile SMS-enabled DID numbers and your applications to the DIDWW SMS network. Use them to receive SMS by email, over HTTP, or over SMPP, and to send SMS through the Outbound SMS API or over SMPP. Create, configure, and monitor SMS trunks in the DIDWW User Panel.
Key features#
Forward inbound SMS to an email address or an HTTP endpoint.
Send SMS from your application through the Outbound SMS API.
Exchange SMS in both directions over SMPP, from your application or your SMSC.
Combine SMS trunks in SMS trunk groups for failover.
Control which DID numbers each trunk can use as the sender of outbound SMS.
Review sent and received messages in the SMS logs.
What is an SMS trunk?#
An SMS trunk defines how messages travel between DIDWW and your systems. For inbound SMS, the trunk assigned to a DID number tells DIDWW where to deliver the messages received on that number. For outbound SMS, the trunk defines the connection settings and permitted senders.
To receive SMS, assign the trunk or a trunk group to your DID numbers. Outbound SMS does not require a DID number to be assigned to the trunk. For an overview of message flows and sender identities, see How SMS service works.
Choose a trunk type#
Trunk type |
Direction |
How it works |
What you need |
|---|---|---|---|
Inbound |
Forwards each inbound SMS to an email address. |
An email address that accepts mail from
|
|
Inbound |
Sends each inbound SMS to your web server or application as an HTTP request. |
An HTTP or HTTPS endpoint that accepts requests from the DIDWW source IP addresses. |
|
Outbound |
Accepts SMS that your application submits to the Outbound SMS API and reports the results to your Callback URL. |
An application that sends HTTPS requests with the trunk credentials. |
|
Inbound and outbound |
Your application connects and binds to the DIDWW SMPP server to send and receive SMS. |
An SMPP client that binds with the trunk’s System ID and Password. |
|
Inbound and outbound |
DIDWW connects and binds to your SMSC as an ESME to deliver and receive SMS. |
An SMSC that accepts bind requests from the DIDWW SMPP server. |
Get started#
Prepare a DID number and an SMS trunk, then assign the trunk and test message delivery.
1. Get a DID number#
To receive SMS, use a DID number that supports Inbound SMS. To send P2P SMS, use a DID number that supports Outbound P2P SMS. To send A2P SMS, use a verified Sender ID instead of a DID number. See Sender ID Verifications.
Filter available numbers by SMS features and buy a DID number.
Choose a payment method and add funds if your prepaid balance is insufficient for the purchase.
2. Create an SMS trunk#
Choose a trunk based on how your systems receive or send messages.
Create an SMS to Email trunk to forward messages to a mailbox.
Create an HTTP IN trunk to forward messages to your endpoint.
Create an HTTP OUT trunk for the Outbound SMS API.
Create an SMPP ESME trunk and bind your application to DIDWW.
Create an SMPP SMSC trunk so that DIDWW binds to your SMSC.
3. Assign and test#
Assign the trunk to receive SMS, then send a test message and review it in the SMS logs.
Assign the trunk or trunk group to one or more DID numbers to receive inbound SMS.
Send a test message to your DID number and confirm it in the Inbound SMS logs.
Review the status, billed fragments, and charges of sent messages.
Configure and manage SMS trunks#
Forward inbound SMS to an email address with a custom subject and body.
Forward inbound SMS to an HTTP endpoint with custom methods, headers, and parameters.
Send SMS through the Outbound SMS API with allowed IP addresses and sender settings.
Bind your SMPP application to DIDWW to send and receive SMS.
Let DIDWW bind to your SMSC for carrier-grade SMS connectivity.
Combine SMS trunks and set their priority order for failover.
Technical references#
Look up the filters, columns, type values, and actions on the SMS Trunks page.
Review the SMPP and HTTP specifications and the Inbound SMS Guidelines.
Look up GSM-7 and UCS-2 limits, reassembly, and fragment billing.