FCC LICENSED CARRIER ·499 FILER ·STIR/SHAKEN CERTIFIED
SIPNEX
Solutions · VICIdial carrier

The SIP carrier VICIdial was waiting for.

Most “VICIdial-compatible” providers are resellers. They sit a tier above the real carrier. SIPNEX is the carrier. We hold our own FCC license, our own 499 filer ID, and our own STIR/SHAKEN SP certificate. That means we sign your calls at A-level ourselves, not downstream at B or C.

Request Dialer-Grade Trunk → See sip.conf config
VICIDIAL CARRIER, DEFINED

A VICIdial carrier is a SIP trunk provider built for VICIdial’s predictive dialing: high concurrent channels, fast call setup, flexible caller-ID handling, and direct STIR/SHAKEN attestation. SIPNEX is that carrier. We are FCC-licensed, hold our own 499 filer ID and STIR/SHAKEN certificate, and sign outbound calls at A-level. There are no artificial channel caps, and trunks go live in 24 hours.

What generic carriers break

A VICIdial floor is not an office PBX. Your carrier doesn’t know the difference.

Attestation drift

Your carrier quietly shifts your attestation from A to B. Analytics engines discount partial (B) attestation — it is a lower-trust signal to them — and there is no carrier-published figure for the answer-rate gap. You find out from a dashboard, not from them.

Channel caps

You were promised “unlimited channels.” Then you hit 50 and start getting 503s during peak hours.

Support that doesn’t know VICIdial

You file a ticket about sip.conf. It gets escalated three times because tier-1 has never seen a dialer.

One carrier, whole stack

VICIdial VoIP provider, dialer trunks, and support — one carrier.

Most operators bolt three vendors together: a VICIdial host, a dialer VoIP provider for termination, and a consultant for when sip.conf breaks. SIPNEX collapses the carrier half of that stack. As a VICIdial VoIP provider, we terminate your traffic as the licensed carrier of record. We sign it at A-level with our own STIR/SHAKEN certificate. And the engineers who answer your tickets run the dialer in production themselves.

That gives you one escalation path from campaign to carrier. Trunks go live in 24 hours. There are no artificial channel caps. Tickets are answered by people who read carrier settings and sip.conf in the same session. Start with the VICIdial SIP trunk setup guide, or compare the field in best SIP trunk for VICIdial.

The carrier checklist

What a VICIdial VoIP provider has to get right.

VICIdial is designed for an Asterisk system with SIP or IAX trunks, so almost any SIP trunk will pass calls. That is not the bar. A predictive dialer stresses a trunk in ways an office PBX never does. Seven carrier-layer decisions decide whether the trunk holds up.

REQUIREMENT WHY VICIDIAL CARES WHAT TO ASK A PROVIDER
Concurrent channels Agents × dial ratio sets the channel count. Fifty agents at 4:1 need 200 channels, and bursts run 20 to 30 percent higher. Is there a hard cap? Which SIP response do you send when I hit it?
Calls per second Hopper refills and ratio changes fire bursts of INVITEs at once. Your written CPS limit. Telnyx’s documented default, for instance, is 20 CPS per source IP.
Codec G.711u gives answering machine detection the cleanest waveform. G.729 compression raises false positives. Native G.711u, with no forced transcoding.
Caller ID VICIdial sets outbound caller ID per campaign, per list, or per lead, and can rotate it per group. The trunk must pass what you set. Do you honor the caller ID I send on numbers I own?
STIR/SHAKEN A-level means the signing carrier verified you and your right to the number. Resellers inherit B-level from an upstream. Who holds the certificate that signs my calls?
Billing increment Dialer calls are short. 60/60 rounding bills a nine-second answered call as a full minute. 12/6 or 60/60? Twilio and Telnyx voice bills 60/60. SIPNEX dialer traffic bills 12/6.
Failure signaling A SIP 503 congests the attempt at once. A trunk that goes silent trips Asterisk’s auto-congest timer instead. Do you send a clear 503 or 403 when you reject a call, or nothing at all?
Capacity math

Size the trunk to your call volume.

Start with agents and dial ratio. Fifty agents at 3:1 need 150 concurrent channels. Add 20 to 30 percent for bursts, because the dialer speeds up the moment answer rates drop.

Then check bandwidth. A single G.711 call takes about 85 kbps each way. Two hundred concurrent calls need roughly 17 Mbps each way. That is modest on a business fiber connection. The G.711 vs G.729 codec comparison has the full math.

The FCC caps predictive-dialer abandons at 3 percent per campaign, measured over 30 days. Headroom is a compliance tool as much as a capacity one. On SIPNEX there are no artificial channel caps. The dialer paces for the abandon ceiling, never for a channel ceiling. Your call volume is bounded by your servers and your bandwidth.

How the pieces fit

Open source dialer, licensed carrier.

VICIdial is open source. Its developer publishes it under the AGPLv2 with no software licensing cost. It is a full contact center suite: predictive dialer, inbound ACD, and blended campaigns in one install. The one thing it does not ship with is a carrier.

Every call still leaves through a SIP trunk. The software is free. The carrier layer is where the operating cost and the compliance exposure live.

Both directions

Inbound, blended, and contact center traffic on the same trunk.

VICIdial handles inbound, outbound, and blended call traffic. One agent can take both directions in a single session. The trunk has to keep up. The DIDs you rotate as outbound caller ID should ring back into your inbound groups when a prospect returns the call.

SIPNEX provisions local DIDs and, as a RespOrg, toll-free numbers. Both ride the same trunk in both directions.

Day-one visibility

Watch the trunk in real time.

VICIdial ships dozens of real-time and summary reports, including real-time campaign display screens. Use them on day one with a new trunk. Watch live channels per campaign, drops, and the Carrier Log Report. When attempts start to congest, the SIP 503 guide separates a real 503 from Asterisk’s AUTO-CONGEST.

Migration

Move a VICIdial floor to SIPNEX in five steps.

  1. Add the carrier. Under Admin → Carriers, give SIPNEX its own Account Entry, Dialplan Entry, and dial prefix.
  2. Set the codec. Use disallow=all, then allow=ulaw, so answering machine detection gets clean G.711 audio.
  3. Pass a test call. Then point one campaign at the new prefix and run it next to your current carrier.
  4. Keep the old trunk as a backup. Every carrier record has an Active field, so you can hold it configured but switched off.
  5. Compare per-carrier results. Same leads, same hours. Move the rest of the floor when the numbers win.

The VICIdial backup carrier and failover guide covers prefix routing and the standing-failover dialplan pattern in detail.

Frequently asked

About VICIdial carrier service.

What is a VICIdial carrier?
A VICIdial carrier is a SIP trunk provider built for VICIdial’s predictive dialing patterns. That means high concurrent channels, fast call setup, flexible caller-ID handling, and direct STIR/SHAKEN attestation. SIPNEX is operator-owned: we run VICIdial ourselves and sell carrier service to other operators.
Why does my dialer need a specific carrier?
Generic carriers throttle high-velocity outbound. Many provide only B-level STIR/SHAKEN attestation. Their support teams don’t speak sip.conf. Dialer operators need unlimited channels, direct A-level signing, smart caller-ID tooling, and engineers who understand VICIdial internals.
Can SIPNEX handle 1,000+ concurrent calls on one VICIdial instance?
Yes. Our trunks have no artificial concurrency cap. You scale channels with your instance capacity, not ours.
How do you prevent CID burn on high-velocity campaigns?
Two things, and both matter. First, direct A-level STIR/SHAKEN attestation, signed with our own SP-KI certificate. Second, caller-ID pool management that works with VICIdial’s dialer logic. Either one alone is not enough.
Do you provide STIR/SHAKEN A-level attestation for VICIdial outbound?
Yes, directly. SIPNEX holds its own STIR/SHAKEN Service Provider certificate. Every outbound call that originates on our network is signed at A-level. Nothing is reshipped through a downstream carrier.
How fast can I be dialing with a new SIPNEX trunk?
Typically 24 hours from signed agreement to live trunk. Complex porting takes longer. Initial DIDs and trunk credentials are provisioned within one business day.
What’s the difference between SIPNEX and Bandwidth or Telnyx for VICIdial?
Bandwidth and Telnyx are generic-first CPaaS carriers. SIPNEX is operator-owned and VICIdial-native. Every decision is tuned for dialer operators: caller-ID tooling, channel capacity, support model, and pricing structure.
Are you TCPA compliant?
SIPNEX provides the carrier-side compliance infrastructure: attestation, call recording controls, and opt-out signaling. TCPA legal duties stay with the caller: consent, DNC scrubbing, and calling hours. We give you the tools. You own the policy.
Does VICIdial work with any VoIP provider?
Mostly, yes. VICIdial is designed for an Asterisk system with SIP or IAX trunks, so any standard SIP trunk will pass calls. The catch is policy, not protocol. Many providers cap channels or CPS, ban autodialer traffic in their terms, or sign calls at B-level through an upstream. A VICIdial VoIP provider allows dialer traffic in writing and signs it as the carrier.
Why does an open source dialer like VICIdial need its own carrier?
Because the software ships without one. Many SaaS dialers bundle minutes and numbers. VICIdial, under the AGPLv2, gives you the dialer and nothing else. You choose the SIP trunk, and that choice sets your attestation level, billing increment, and CPS ceiling. The upside is control: you can run two carriers, route campaigns by dial prefix, and switch when one degrades.
What happens in VICIdial when the carrier starts rejecting calls?
Every attempt congests — whether the carrier sends a SIP 503 or simply stops responding (Asterisk’s auto-congest timer). The Carrier Log Report fills with congestion statuses. Recovery is a routing decision: swap the campaign’s dial prefix to a backup carrier, or add a second Dial line as the next dialplan priority.

Related Guides

More Solutions

Predictive DialerCall CenterPolitical PollingWholesale VoIPWholesale Voice TerminationWholesale SIP TrunkingVoIP Reseller ProgramTwilio AlternativeTeams Direct RoutingPOTS Replacement

Get a trunk in 24 hours.

Tell us your instance count and monthly minutes. We’ll quote you in one business day.

Request Dialer-Grade Trunk →