Does Open work with Vonage Voice API?

Yes. Use a `connect` action in your NCCO with an `endpoint: sip` block targeting the Open SIP URI. Vonage handles the call leg, Open answers as the AI.

Does Open work with Vonage SIP Trunking?

Yes. Add Open as a termination URI on your Vonage SIP trunk. Vonage routes the inbound INVITE to Open and the AI picks up.

Can I keep my Vonage phone numbers?

Yes — every Vonage LVN or toll-free stays on Vonage. You're only changing where the call leg gets sent, not who owns the number.

What does this cost on top of Vonage?

Vonage continues to bill carrier minutes and Voice API usage at-cost. Open charges per resolved conversation — no markup on Vonage minutes, no per-seat fees.

Can the AI transfer to a human via Vonage?

Yes. Open supports SIP REFER and direct PSTN bridging via Vonage, so a live agent gets the call along with the AI transcript and detected intent.

Is the SIP signaling secure?

Open supports SIP over TLS for signaling and SRTP for media. Pick TLS when configuring the trunk — Vonage supports both.

How do I route different Vonage numbers to different AI agents?

Either map the numbers in the Open dashboard, or pass a custom routing header from your NCCO so Open picks the right agent at INVITE time.

How long does setup actually take?

Inbound is typically under 10 minutes once your Vonage application or SIP trunk is in place. Outbound trunks take a few extra minutes to enter host, credentials, and caller ID.

CPaaS · Voice API

Open for Vonage

Point a Vonage Voice API application or SIP trunk at Open and the AI picks up — in your numbers, your dashboards, your stack.

Try now

Setup time: Under 10 minutes
Auth: Digest credentials, JWT, or IP allowlist
Directions: Inbound · Outbound · Call transfer
Pricing: Included with Open

01 — Overview

Can I run an AI phone agent on my Vonage Voice API or SIP trunk?

Yes. Open plugs into Vonage as a SIP destination — your Vonage application, numbers, and Voice API webhooks keep working unchanged, and the AI takes the call wherever you decide to route it.

Open is not a Vonage replacement. Your Vonage account remains the source of truth for numbers (LVNs and toll-free), billing, and call routing. The AI lives behind a SIP endpoint Vonage already knows how to talk to. When a call needs to be answered by AI, your Voice API NCCO or your SIP trunk's outbound rule sends the leg to Open, and the AI picks up over the same SIP/RTP session your existing Vonage flows already use.

For inbound calls, the most common path is a connect action in your NCCO that targets the Open SIP URI, or — if you're on Vonage SIP Trunking — an outbound termination rule that points to Open. Both are 5-minute changes in the Vonage Dashboard. The webhooks you already use for events, recording, and analytics all keep firing because Vonage is still the controlling side of the call leg.

For outbound, Open opens a SIP session against your Vonage SIP termination URI using the digest credentials Vonage issues per trunk. Calls show up in your Vonage application's CDRs the same way human-dialed calls do, and they present the caller IDs you've already verified on the Vonage side. AI-driven outbound campaigns — payment reminders, lead callbacks, win-back, surveys — all run from Open while staying invoiced on Vonage.

What the AI does on the call is where Open earns its keep. It listens, reasons over your knowledge base and the tools you've connected (Salesforce, HubSpot, Zendesk, Shopify, Stripe, Calendar), and acts: looking up an order, creating a ticket, scheduling a callback, sending a payment link, or warm-transferring to a human via SIP REFER with the live transcript and detected intent attached. Every call is recorded and trace-logged, so you can replay why the AI made a decision, not just what it said.

Billing stays predictable. Vonage charges you at-cost for carrier minutes, exactly like today; Open never marks them up. Open charges per resolved conversation, not per agent or per seat — so spinning up ten AI agents on ten Vonage numbers costs the same baseline as spinning up one.

What stays the same on Vonage

Vonage numbers and billing
Your LVNs, toll-frees, and Vonage invoice don't move. No porting, no carrier change.
Voice API NCCOs and webhooks
Your application stays in control of routing. Open plugs in as a `connect → SIP` destination.
Approved caller IDs
Outbound calls present the caller IDs Vonage has already verified on the trunk you point Open at.
CDRs, recording, analytics
Every call leg still lands in the Vonage Dashboard. Open adds AI-side reasoning traces on top.

What's new with Open

A SIP destination on Vonage
You add Open's SIP URI as a `connect` endpoint in your NCCO or as a SIP trunk termination rule.
AI handles the conversation
The AI greets, listens, calls your tools, and replies in natural speech — instead of a queued human or a static IVR.
Transfers carry context
When humans take over via SIP REFER, they receive the live transcript, detected intent, and customer record.
Pricing model
You pay Open per resolved conversation. Carrier minutes and Voice API usage stay invoiced by Vonage.

02 — Why this works

The native Vonage experience

Native SIP — no middleware
Open registers as a SIP endpoint your Vonage application or trunk talks to directly. No proxy, no extra hop, no markup on Vonage minutes.
Bring your own Vonage numbers
Keep your LVNs and toll-frees on Vonage. Map any number to a specific AI agent via the dashboard or a routing header.
Voice API + SIP Trunking, both work
Whether you live in Voice API NCCOs or rely on Vonage SIP Trunking, Open slots in as a destination either way.
Multi-region SIP endpoints
Pick US, EU, APAC, or global auto-route to keep call setup latency low wherever your Vonage numbers terminate.

03 — Setup guide

Wire up Vonage in under 10 minutes

Two trunks — one inbound, one outbound. Both configurable from Settings → SIP in the Open dashboard.

1
Open Settings → SIP
In the OpenCX dashboard, go to Settings → SIP and open the inbound trunk configuration.
2
Pick a SIP region
Choose Global (auto-route), US, EU, or APAC depending on where your Vonage numbers terminate. The endpoint address updates automatically.
3
Copy the SIP credentials
Grab the generated SIP endpoint, username, and password — these are what your Vonage application or SIP trunk will use to send calls to Open.
4
Update your Vonage NCCO (Voice API path)
In your Vonage Voice API webhook, return an NCCO with a `connect` action whose `endpoint` is `sip` and whose URI is the Open SIP endpoint from step 3. Pass digest credentials in the `headers`.
5
Or configure a SIP Trunk termination rule
In Vonage Dashboard → SIP Trunking, add Open as a termination URI for your inbound numbers. Use the same credentials.
6
Add your Vonage numbers (DIDs) to Open
Under Phone Number (DID) in OpenCX, add each Vonage LVN that should route to this trunk in the exact format Vonage sends in the INVITE.
7
Assign numbers to an AI agent
In Channels → Phone → Agents, open the agent and assign the inbound numbers under Telephony & Routing.
8
Place a test call
Dial one of the Vonage numbers and confirm Open answers. The full call transcript will appear in your Open inbox.

04 — Configuration

Settings → SIP, at a glance

A real inbound trunk for Vonage looks something like this. Yours are generated when you open Settings → SIP.

Inbound trunk · Vonage

Sample

SIP endpoint: sip.eu.opencx.comEU region
Transport: TLSrecommended
Username: open_inbound_v0nage…
Password: ••••••••••••••••
NCCO action: connect → endpoint=sip

05 — Security

Encrypted, audited, refundable

SIP over TLS for signaling, SRTP for media. Every call is logged with full reasoning traces. SOC 2 Type II, GDPR-aligned, HIPAA- and PCI-ready. Backed by the Open $2M Refund Guarantee.

06 — FAQ