Phone numbers and caller identity

No other event stops an outbound programme faster than a “Spam Likely” label on the screen. LeadRefinery manages each phone number as a reputation asset with a sequence of stages. The platform increases a number's daily calls slowly, spreads its use evenly, and watches how each of its calls ends. When a number shows spam signals, the platform removes the number from service immediately.

Why numbers are the fragile asset

Phone carriers analyse the calling behaviour of every number, and they attach labels to the results. “Spam Likely” is the most damaging label. When it appears on screens, the answer rates decrease sharply. A label also stays on a number for a long time.

A careless outbound programme produces exactly the behaviour that gets a label. Two examples: a new number that suddenly makes many calls to strangers, and short calls where people answer and immediately end the call. Thus the platform increases each number's use slowly, keeps the use inside the limits, and never uses all of the capacity at one time.

A diagram of the stages of a phone number. The healthy top row goes from left to right. First, a person buys the number and adds it to the client's pool. Then a warm-up stage increases the calls from twenty-five each day to seventy-five each day across ten working days on which the number dialled. Then the number is in full service, with a hard limit of seventy-five calls each day. For each call, the platform selects the healthy number with the least use. An amber trouble row is below. When a number's answer rate decreases sharply — people answer but end the call within seconds — the platform slows the number to twenty-five calls each day. A spam label, or one complaint, removes the number from service, to zero calls, immediately. One arrow goes from the removed state back into the warm-up stage, never directly back to full speed. A grey arrow goes on to retirement, where the record stays permanently. A note with a padlock states two facts for all stages: the number has one owner permanently, and the carrier signs each call. — The healthy path is across the top: added, then warm-up, then full service. The trouble path is below it. The only route back from trouble goes into warm-up, never directly to full speed. The padlock shows two permanent facts: the number has one owner only, and the carrier signs each call.

A number's career

Added first

A person buys the number at Telnyx, tags it with its environment, and adds it to the client's pool. The platform does not yet ask Telnyx how the scoring companies grade the number before its first call. It does not enter the number with those companies, and it does not ask them to review a wrong label. A daily read of each number's own standing, built and connected to Telnyx, exists but is switched off everywhere, because each fresh reading is billed; Number reputation explains the gap. Today the first signal about a number comes from its own calls: a block by the network takes the number out of service at once. (open gap)

Warming up

A new number starts at 25 calls each day. It makes 25 calls each day for five working days, then 50 each day for five more, and it reaches 75 on the eleventh working day. A working day counts only if the number dialled on it. No one can compress this schedule. Only real calls to real people increase carrier trust.

In service

In full service, three rules apply:

Full speed is a hard limit of 75 calls each day.
For each call, the platform selects the healthy number with the least use in the client's pool. Thus the use spreads evenly across the pool, and no single number gets too much use.
The claim of a number for a call is one indivisible operation. Two calls can never take the same last slot.

Throttled

When a number's answer rate decreases sharply below the rates of the other pool numbers, the platform slows the number to 40 calls each day. Today the code holds a limit of 25 calls. The change is decided, and it is not built yet. The typical signal is this: people answer, and then they end the call within seconds. That signal shows the effect of a spam label, frequently before the label is visible.

Quarantined

A block by the network during a call removes the number from service fully, the moment the call ends. A carrier spam label or one complaint would do the same, but neither input reaches the platform today: the label read from Telnyx is switched off everywhere, and the phone company sends no complaint feed. The platform does not treat complaints as a rate to manage.

Recovery, the slow way

A recovered number returns to service through the warm-up stage, never directly at full speed. A return at full speed is the fastest route to a new, stronger label.

Retired, or removed

A number that has placed calls is retired, and its history stays. Thus the question “why was this number quarantined last spring?” always has an answer. A number that never placed a call is removed outright when staff take it out of the pool, and its binding at Telnyx is removed with it.

Verified caller identity

Telnyx, the carrier, signs each outbound call with the phone industry's standard signature. The signature shows that the call comes from its correct owner. The receiving networks use that signature when they decide what to show on the screen. The signature has three grades. Which grade Telnyx gives these calls is not yet confirmed with Telnyx, and the platform does not read it. (open gap)

For the attestation at full strength, the carrier must know the client. Each number must have a documented, verified business identity. Every number belongs to exactly one real client, permanently, so the signature points to the one business with the right to make the call, and one client's behaviour cannot damage another client's numbers. The platform refuses outright to add a number to a second real client's pool; the first client must give it up before a second one can take it. Only a demo or test organization's number can be shared, and only after a staff member confirms it. When that happens, the platform ties the number's daily call limit and its health together across every holder, and the number's settings screen names every one of them.

The pool works as a team

Even use is a property of the full pool. Because of the least-used-first rule, no number collects use more quickly than the other numbers. The pool's daily capacity is also one of the limits that the day-zero release plan checks before it admits a lead. Thus reputation protection controls the count of leads that the platform can safely take on.

Texts come from one fixed number

A pool number never sends a text. Each environment sends its texts from 1 fixed number that Telnyx registered for texting: the code that proves a person holds a number before a demonstration call, and the application link after a call. That registration requires three standard replies: "STOP" opts the phone out, "HELP" sends a short support message, and "START" gets a reply but never opts a person back in. A "STOP" also stops calls to that phone, in every client at once, through the do-not-call suppression list. How the platform uses Telnyx gives the detail.

LeadRefinery staff can add a number to a client's pool directly from that client's own settings screen, without first switching into the client's workspace, and can add several numbers from the carrier's own inventory in one action rather than one at a time. The picker greys out a number that is set aside for a different deployment environment, such as the platform's own test systems, and states why, so staff cannot add a test number to a real client's pool by mistake.

One honest note

A daily health assessment moves the numbers between these stages. The assessment examines the answer rates, the short-call patterns, and the complaint reports. A daily job runs the assessment for each client, and the same job moves each warming number one step along its schedule. Today:

Three things move a number on their own: a block by the network during a call, a day on which more than half of 20 or more dials failed, and the timers that bring a number back. A carrier label and a complaint would too, but neither input reaches the platform today. The rules on answer rates and short calls are decided, and they are not built yet.
Operators can release a number from quarantine early, retire or remove it, and withdraw or restore its registration. Withdrawing the registration throttles an active number at once. No screen moves a number to throttled, or back, by hand.
The daily limits, the least-used selection, and the indivisible claims fully operate in the calling path.

The technical bit, translated

Telnyx is the carrier. It supplies each client's numbers, places the calls, and reports the network events. It also signs each call under the telephone industry's caller-attestation standard, with the trade name STIR/SHAKEN. That signature is a cryptographic proof of the caller's identity.
Number reputation is a Telnyx service. It reads the scoring networks that the major carriers consult, and it returns a risk of low, medium or high for each number, with scores for age, connection, engagement and sentiment. The platform is built to use Telnyx for this and to speak to no scoring company itself, but the connection is not yet made.
PostgreSQL holds the daily counters for each number, and it performs the indivisible claim. The database takes one slot in one indivisible step. Thus two simultaneous calls can never increase a count above the limit.

Where to next

How the platform uses Telnyx — the account, the four environments, how a call and a text go through the carrier, and what a person sets up by hand.
The seventeen checks before we dial — the healthy-number claim occurs there on every call.
Many clients, one platform — why each client's numbers normally stay separate, and what happens on the rare number that does not.
Running a calling campaign — the pool capacity sets the limit on the daily lead releases.