
Before You Begin
Collect the SIP phone number, termination URI, authentication method, expected caller ID behavior, and one published agent version for testing. For IP-based authentication, ask DialNexa support for the signaling IP used in your region and have the SIP provider allow it before saving the trunk.DialNexa SIP Trunking Versus Number Purchase
Fields In The SIP Trunk Modal
IP-based authentication sends no SIP username or password. The provider authorizes outbound calls by the DialNexa signaling source IP. If provider IPs are not configured for inbound matching, outbound calls can work while inbound INVITEs cannot be mapped to the trunk.
Link And Validate A SIP Number
1
Open Phone Numbers
Use the Phone Numbers page to start the SIP linking flow.
2
Choose the authentication method
Use Username & Password when the provider issued SIP credentials. Use IP-based authentication only after the provider has allowlisted the DialNexa signaling IP.
3
Enter the SIP details
Provide the phone number and termination URI. Enter both credentials for username and password authentication. Leave both absent for IP authentication.
4
Assign published versions
The number still needs inbound or outbound published agent versions. SIP decides the route, not the conversation behavior.
5
Place an inbound test
Confirm the correct agent answers, the caller hears audio, and Call History stores the call.
6
Place an outbound test
Confirm caller ID, audio quality, transcript quality, status, duration, and end reason.
SIP Audio Review
SIP-routed calls use phone-grade audio. The exact quality depends on your carrier and trunk configuration.SIP Failures Before Ringing
Both reasons produce a failed call before a useful conversation starts. Correct the route, then place a new test call. Repeated retries without a configuration change are unlikely to help.
Troubleshooting
Calls fail immediately
Calls fail immediately
Check phone number format, termination URI, authentication method, and whether the linked number is active. Username and password mode requires both credentials. IP mode rejects credentials and requires provider allowlisting.
Outbound works but inbound calls do not arrive
Outbound works but inbound calls do not arrive
For IP-authenticated trunks, confirm the provider’s signaling IPs are configured for inbound endpoint matching and that the provider sends traffic to the expected DialNexa route.
Audio is one-way or distorted
Audio is one-way or distorted
Review trunk media settings, recording, and transcript. Compare against a Plivo or web call if you need a baseline.
Wrong agent answers
Wrong agent answers
Phone number assignment controls the agent. Check inbound and outbound published versions.
Transfers behave differently
Transfers behave differently
Test transfer behavior through the exact trunk before production use.
Verify The SIP Trunk
Place one controlled test call. Confirm that the correct agent answers, both sides can hear clearly, caller ID is expected, and Call History stores the correct direction, route, status, and recording.Related Reading
Phone Numbers
Manage number status and assignments.
Audio Quality
Review recording and transcript quality.
Call Transfer
Test handoffs through the trunk.
Call History
Audit SIP-routed calls.