How to Pick a Termination Carrier for Your Dialer

A buyer's checklist for choosing SIP termination for an outbound dialer: the ASR, ACD, and PDD benchmarks to demand, the CPS games carriers play, and the red flags.

How to Pick a Termination Carrier for Your Dialer
Vibratel Team5 min read

Most carriers are happy to sell a call center termination knowing full well they cannot complete the calls your dialer attempts. The rate sheet will not tell you that. The sales rep will not volunteer it. You find out three days after you sign, when the data comes back and your agents are talking to silence.

This post is the checklist we would want if we were on your side of the table. It works on any provider, including us. Walk a sales rep through it, and the ones who dodge half the questions answer the question for you.

Why per-minute price is the wrong first question

Cheap routes are not cheap. They recover their margin somewhere, and on a dialer that somewhere is usually false answers and dead air, aggressive throttling, or routing your traffic down a chain of cheapest-available downstream carriers whose behavior you inherit.

So price is the last question, not the first. Decide which carriers can actually carry your traffic at quality, then compare price among the ones that pass. A route that is two-tenths of a cent cheaper and burns a third of your talk time on silence is the most expensive route you can buy.

The metrics to ask for, with benchmarks

Make the provider put numbers next to these. Vague answers are themselves a data point.

The capacity questions carriers dodge

This is where the quiet games live, and where most operators forget to push.

Ask for your CPS ceiling, calls per second, and your concurrent-channel ceiling, in writing. Predictive dialers burst hard, and an unstated cap will throttle you without warning. A common trick is a plan sold as "100 channels" that quietly starts rejecting calls past eighty to push you toward an upgrade. Another is a gateway that simply returns errors once your dialer exceeds a CPS limit nobody told you about, so your dialer reads it as "idle" instead of "blocked."

Then ask the follow-up most operators skip: what is your published channel ceiling, and can I burst above it the same day or do I file a ticket and wait? A provider that is straight with you answers this with a number. One that hedges is telling you something.

Red flags

If you see these, keep shopping:

Green flags

What a route built for dialer traffic looks like:

Those are the things our termination product is built around, and they are the things worth holding any carrier to.

The 60-second test before you sign

You do not need a procurement process to vet a route. You need one live batch and your own CDRs.

  1. Run a small live batch through the new carrier on the same scrubbed list you are running today.
  2. Pull the call detail records.
  3. Check ASR, ACD, PDD, and the dead-air rate against your current carrier, side by side on the same data.
  4. The winner is obvious, and it is measured on your traffic, not their slide deck.

A termination carrier is infrastructure, not a logo. The right one is the one whose numbers hold up when you run your own calls through it and read the records yourself. Everything above is just how to make sure you are reading the right numbers before you commit, instead of three days after. When you are ready to pick numbers and routing in volume, the bulk DID and termination side of the network is built for exactly that.

Vibratel Team

Telecom operators & product team at Vibratel.

Vibratel runs its own carrier network. What you read here comes from the people who operate it, based on what we have actually built, broken, and fixed in production.

Frequently asked questions

What ASR should I expect on a dialer?

Answer seizure ratio is the share of attempts that connect. On a dialer it runs lower by nature, so judge it by trend and by route, not against a single benchmark. As a rough guide, 60 percent and up is strong, 40 to 50 is acceptable, and under 40 deserves scrutiny. Premium routes can sit above 80. What matters most is comparing two carriers on the same list rather than trusting one number in isolation.

What is CPS and how much do I need?

CPS is calls per second, the rate at which your dialer is allowed to launch new calls. Predictive dialers burst hard, so an unstated or low CPS cap will quietly throttle you and your dialer will sit idle. Ask for your CPS ceiling and your concurrent-channel ceiling in writing, and ask what happens when you exceed them. The honest answer is a number, not a shrug.

Do I legally need STIR/SHAKEN to terminate in the US?

Yes. US outbound calling has to be STIR/SHAKEN signed, and any provider selling you 'non-CLI' or grey routes is selling you a path that fails authentication and lands in the spam folder. If a carrier cannot sign your calls, that is disqualifying, not a detail.

Can I test a termination carrier before I commit?

You should insist on it. A real provider lets you run live traffic and pull the call detail records so you can check ASR, ACD, PDD, and dead air against your current carrier on the same data. If a provider will not let you test on live traffic before you sign, that is the answer.

What's a healthy ACD for outbound?

Average call duration depends heavily on your campaign, but the warning sign is universal: an ACD near zero to one seconds means calls are connecting and dropping instantly, the signature of a bad route or false answers. You are looking for an ACD that reflects real conversations, not a pile of one-second 'connects.'

Still have questions? Talk to sales →

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