Zentrix Agent Studio uses a verified Indian telephony partner to provide phone numbers (+91) for your AI voice agents. When a customer dials your assigned phone number, the call routes through the telephony network to the voice AI platform, where your AI agent answers and handles the conversation.
The voice call architecture works as follows:
Caller dials +91 number
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Indian telecom network (verified carrier)
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Voice AI platform (speech processing)
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Your AI Agent (prompt + knowledge base)The telecom layer handles SIP, PSTN, and number management, while the voice AI platform handles the conversation layer (speech-to-text, AI processing, text-to-speech). The native integration between these layers means there is no custom bridge server required -- calls flow directly with sub-second latency.
| Type | Format | Use Case |
|---|---|---|
| Local | +91 20 XXXX XXXX (city code) | Standard business line, local presence |
| Toll-Free | 1800 XXX XXXX | Customer support lines, enterprise use |
| Virtual | +91 XXXX XXXX XX | Flexible routing, no physical location |
Numbers are provisioned by the Zentrix Agent Studio admin team and assigned to your agent instance. See Phone Numbers for provisioning options and pricing.
| Option | Markup on Base Cost | Setup Time | Setup Fee |
|---|---|---|---|
| Self-Serve | 20% | 4 business hours | Free |
| Managed | 35% | 24 hours | Free |
| Bring Your Own Number (BYON) | No markup | 24-48 hours | Rs 1,499 one-time |
For BYON, you port your existing business number to work with Zentrix Agent Studio. The porting process is handled by our team and typically completes within 24-48 hours.
The telephony network delivers audio to the AI platform in the following format:
| Parameter | Value |
|---|---|
| Encoding | Base64-encoded, 16-bit PCM |
| Sample Rate | 8 kHz (standard) or 24 kHz (high quality) |
| Channels | Mono |
| Byte Order | Little-endian |
The 24 kHz sample rate provides better speech-to-text accuracy and is used by default when available. Audio format conversion is handled automatically by the voice AI platform.
| Feature | Status |
|---|---|
| Inbound calls | Fully supported -- caller dials your number, AI agent answers |
| Call recording | Available -- recordings stored securely and accessible from call logs |
| Caller ID | Included in the WebSocket start event, used by the identify_caller tool |
| Call transfer | Supported -- AI agent can transfer to another number (human or second AI agent) |
| IVR integration | Available for advanced routing scenarios (enterprise tier) |
| DTMF | Supported -- callers can press keys for menu navigation if configured |
| Call data webhooks | Post-call analytics (duration, cost, status) delivered via webhook |
The native integration between our telephony and voice AI platforms achieves:
This is fast enough for natural-feeling conversation with minimal pauses between the caller speaking and the AI agent responding.
Tip: For detailed instructions on getting a phone number assigned to your agent, see Inbound Calls. For understanding how phone numbers are priced, see Phone Numbers.
A Product by BRTNeura Technology LLP
Last updated: 2026-03-05