If you're new to virtual numbers, it helps to understand what's actually happening between the moment someone dials your number and the moment your phone rings. It's simpler than it sounds — no special hardware, no wiring, no phone company visit required.
First: what makes a number "virtual"?
A traditional phone number is tied to a physical line at a physical address — think of the landline wired into an office wall. A virtual number isn't tied to any physical location at all. It exists on AVOXI's network in the cloud, which means:
- You can have a number for a country or city where you don't have an office
- You can change where calls get routed at any time, instantly, without a technician
- You can route the same number to different destinations depending on the time of day, the caller's location, or your team's availability
That flexibility is the entire point of a virtual number — the number is just an address; where the call actually ends up is up to you.
The two "legs" of every call
Every call to a virtual number happens in two parts. Providers (AVOXI included) call these the origination leg and the termination leg.
1. Origination — the call comes in Your customer dials your number. Their local carrier hands that call off to AVOXI's network. This part is entirely outside your control — it's just the call reaching us.
2. Termination — the call goes out to you This is where your setup comes in. Once AVOXI has the call, it gets routed to wherever you've configured it to go. There are three common ways this happens:
- SIP Trunk — the call is delivered over the internet directly to your phone system (PBX, contact center platform, softphone). This is usually the most cost-effective and flexible option.
- PSTN Forwarding — the call is forwarded to a traditional landline.
- Mobile / Alternate Destination — the call is forwarded to a mobile phone, a different office, or a backup number entirely.
You can also set these up with automatic failover — for example, try the SIP trunk first, and if it doesn't answer, fall back to a mobile number — so a call never just disappears because one route was unavailable.
What happens in between
Between origination and termination, your AVOXI platform can apply whatever call handling you've set up:
- IVR menus ("Press 1 for Sales, Press 2 for Support")
- Business hours routing (send calls to voicemail or a different team after hours)
- Call recording
- Number-based rules (route certain area codes or countries to a specific team)
None of this changes the two-leg structure above — it just determines how the termination leg gets decided before the call actually connects.
Outbound calling works the same way, in reverse
When you make an outbound call from an AVOXI number, your caller ID is what your recipient sees on their end — this is why choosing the right number type (local, toll-free, TrueLocal) for outbound calling matters just as much as it does for inbound. A local caller ID in the recipient's own country is generally more likely to be answered than an unfamiliar international one.
Why call quality can vary by destination
Because every call travels over the internet rather than a dedicated physical line, factors like which data center handles your traffic and the distance between your caller and that data center can affect call quality. This is why AVOXI lets you choose or test data center routing for certain number types, and why we offer Call Quality Insights (MOS scoring) so you can monitor this over time instead of guessing.
Quick recap
- Someone dials your virtual number → origination leg starts
- AVOXI's network receives the call and applies your configured routing (IVR, business hours, etc.)
- The call is delivered to your chosen destination (SIP trunk, PSTN, mobile) → termination leg completes
- The whole process happens in real time, over the internet — no physical wiring involved
Related articles:
- Virtual Number Glossary: Key Terms Explained
- AVOXI Geo Genius: Data Center Overview
- Configuring Basic Call Forwarding
- Call Quality Standards (MOS)
- Direct Inward Dialing (DID) vs. Toll-Free: Which Do I Need?
