Documentation Index
Fetch the complete documentation index at: https://plivo.com/docs/llms.txt
Use this file to discover all available pages before exploring further.
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.
