Set up an SMS Channel for SIPTRUNK
A SIPTRUNK SMS channel ties a SIPTRUNK DID number to your Cloud Voice system, letting agents hold text conversations with customers right inside the Cloud Voice App. The setup runs in three stages: you generate a webhook URL in Cloud Voice, register that webhook and an API key over in SIPTRUNK, then build the channel in Cloud Voice with the SIPTRUNK credentials and number.
Requirements
Section titled “Requirements”On your Cloud Voice system
Section titled “On your Cloud Voice system”- Firmware: Version 84.23.0.24 or later.
- Domain name: The domain must contain no underscore characters. An underscore causes the channel to fail authentication or stop receiving messages, because the third-party platform rejects it.
- Domain certificate: A valid domain certificate must be installed.
On SIPTRUNK
Section titled “On SIPTRUNK”- Telephone number: The DID number (or numbers) must be SMS/MMS capable and registered for 10DLC.
Supported message types and limits
Section titled “Supported message types and limits”The SIPTRUNK channel carries both plain text messages and multimedia messages (MMS). Which MMS file types are accepted is set by SIPTRUNK.
| Limit | Value |
|---|---|
| Maximum file size | 100 MB |
| File retention period | 72 hours |
Step 1. Get a webhook URL from Cloud Voice
Section titled “Step 1. Get a webhook URL from Cloud Voice”You need this URL when you set up the number in SIPTRUNK, so obtain it first.
-
Sign in to the PBX web portal and go to Messaging > Message Channel.
-
Click Add and choose SMS.
-
In the ITSP list, select SIPTRUNK, then copy the Webhook URL.

Step 2. Configure messaging in SIPTRUNK
Section titled “Step 2. Configure messaging in SIPTRUNK”Sign in to the SIPTRUNK customer portal and complete the following.
-
Note the DID number you want to add to the SMS channel.

-
Set up a messaging webhook for that DID number.
-
Create a webhook using the webhook URL you copied from Cloud Voice.

-
Assign the webhook to the DID number.

-
-
Create an API key for the Cloud Voice integration, then note the Access Key and Secret Key.

Step 3. Create and configure the SMS channel in Cloud Voice
Section titled “Step 3. Create and configure the SMS channel in Cloud Voice”Now build the channel and fill in the credentials and number you got from SIPTRUNK.
-
In the PBX web portal, go to Messaging > Message Channel.
-
Click Add and choose SMS.
-
On the Authentication tab, enter your SIPTRUNK details.

- Name: A label that makes the channel easy to recognize.
- ITSP: Select SIPTRUNK.
- Access Key: Paste the access key from SIPTRUNK.
- Secret Key: Paste the secret key from SIPTRUNK.
-
On the Messaging Settings tab, configure how the channel behaves.
-
In Message Sending Rate, set the number of messages the system may send per second.
-
Set the session options as needed.
Setting What it does Close Session Automatically Select this to have the system end sessions that have gone quiet for a set time, then enter the number of days in Session Timeout (Days). Allow the Creation of Duplicate Active Sessions Select this to let a new session start even when an active one already exists between the same sender and receiver. When an agent tries to start such a session in the Cloud Voice App, a prompt appears; if the agent continues, the existing session (with its full chat history) leaves the previous handler’s list and moves to the new agent. 
-
In the Number section, click Add to create a message routing rule.

-
Number: Enter your provisioned number or an alphanumeric sender ID.
-
Destination for Inbound Messaging: Choose where messages to this number are delivered.
Option What it does Extension Pick an extension from the Extension list. Only that extension user receives inbound messages from the number. Message Queue Pick a queue from the Message Queue list. Every agent in the queue sees new inbound sessions, but once an agent picks up a session, only that agent receives and answers its follow-up messages. Third-Party Message Analytics Platform (Transmitted via API) Inbound messages are forwarded automatically to an external analytics platform over the API for further processing. -
Extensions allowed to create messaging sessions: Select the extensions that may start a messaging conversation with customers.
-
-
Click Save.
-
-
Click Save.
Result
Section titled “Result”-
The channel appears in the message channel list with a green Status indicator
, confirming it was created successfully.
-
The system tracks how many messages the channel sends and receives. The Total column shows all sent messages, both delivered and failed.

What to do next
Section titled “What to do next”Send a text message to your channel’s phone number and confirm that the assigned agent receives it in the Cloud Voice App.