Connect Plivo SIP trunking to Vapi to enable your voice AI assistants to make and receive phone calls through Plivo’s global voice network.
Prerequisites
| Requirement | Description |
|---|
| Plivo Account | Sign up with SIP trunking enabled |
| Phone Number | Purchase a voice-enabled number |
| Vapi Account | Create account |
India not supported: Indian phone numbers are not compatible with Vapi due to TRAI regulations requiring SIP termination on Indian servers. Vapi does not currently support this requirement.
Optimize for latency: For best call quality, ensure your Vapi deployment is in a region closest to your call traffic. This minimizes audio delay and improves conversation flow.
Part 1: Make Outgoing Calls
Enable Vapi to make outbound calls through Plivo.
Step 1: Create IP Access Control List in Plivo
Vapi uses IP-based authentication for outbound calls.
- Go to SIP Trunking → Outbound Trunks → IP Access Control List
- Click Create New IP Access Control List
- Enter a name (e.g.,
Vapi-IPs)
- Add the following Vapi IP addresses:
44.229.228.186/3244.238.177.138/32
- Click Create
Step 2: Create an Outbound Trunk in Plivo
- Go to SIP Trunking → Outbound Trunks
- Click Create New Outbound Trunk
- Enter a name (e.g.,
Vapi-Outbound)
- Select the IP Access Control List you created
- Click Create Trunk
- Copy your Termination SIP Domain (e.g.,
XXXXXXXXXXXX.zt.plivo.com)
Use the termination domain from Plivo to configure outbound calling in Vapi. See Vapi Plivo integration guide for detailed steps.
Part 2: Receive Incoming Calls
Route calls from your Plivo phone number to Vapi.
Step 1: Create an Inbound Trunk in Plivo
- Go to SIP Trunking → Inbound Trunks
- Click Create New Inbound Trunk
- Enter a name (e.g.,
Vapi-Inbound)
- Click Add New URI and configure:
| Field | Value |
|---|
| Name | Vapi-Primary |
| SIP URI | sip.vapi.ai;transport=udp |
- Click Create Trunk
Step 2: Connect Your Phone Number
- Go to Your Numbers
- Click on your phone number
- Set Application Type to
Zentrunk
- Set Trunk to your inbound trunk
- Click Update Number
Register your phone number in Vapi to accept incoming calls. See Vapi Plivo integration guide for detailed steps.
Troubleshooting
| Issue | Solution |
|---|
| Call doesn’t connect | Verify SIP URI uses transport=udp for inbound. Check IP ACL for outbound. |
| Outbound calls failing | Verify Vapi IP addresses are correctly whitelisted in IP ACL. |
- Inbound issues: Check Plivo logs first
- Outbound issues: Check Vapi logs first
For error codes, see Plivo hangup codes.
