The meter rounds down

1 August 2026billingmetering

The meter rounds down

Usage billing has one failure mode that costs you a customer and one that costs you a little money. We picked the second, everywhere, on purpose.

Sample post. This is placeholder editorial used to build out the blog — the layout is real, the article is not published, and it is excluded from the feed and from search.

Metered infrastructure bills for something the customer cannot see. They get a number at the end of the month and no way to check it. That asymmetry means a metering system is really a trust system, and trust systems fail in one direction much worse than the other.

Overbilling once costs you the account. Underbilling costs you the difference.

The rule

Every path through our metering pipeline errs downward. When a component cannot establish how much was used, it records less rather than more — and where it cannot establish anything at all, it records nothing.

That sounds obvious stated plainly. It stops being obvious the moment you write the error handling, because the convenient default in almost every failure case is to assume the expensive thing:

A telemetry sample arrives late, after the session it belongs to has closed. Attribute it, or drop it?
A device drops off the network without a clean goodbye. Bill until the last confirmed sample, or until the timeout that eventually reaps it?
A relay allocation is created but the stream never starts. Charged, or not?

Answer those one at a time, under deadline, and you will answer them inconsistently. Answer them once as a rule and they answer themselves.

A session's carried span runs longer than its billed span: billing stops at the last confirmed sample, and the remainder up to the reaping timeout is uncharged. Below, three ambiguous events — a late sample, a missing goodbye, an unused allocation — each resolved downward. — The gap is deliberate, and it is the shape of every ambiguous case.

What it costs

Real money, and not a rounding error. A device that disappears without a goodbye is billed only to its last confirmed reading, and the gap between that and the reaping timeout is relay we provided and did not charge for.

We think that is the correct trade. The alternative is a support conversation where the customer is right and we cannot prove otherwise, and that conversation is more expensive than the relay.

Undercounting is only defensible if it is deliberate and bounded. A pipeline that silently loses usage for reasons nobody chose is not conservative — it is broken, and it happens to be broken in a direction you have not noticed yet.

Relay is the line item that matters

Peer-to-peer connections cost us nothing to carry, so they cost you nothing. What gets metered is relay — the fallback that carries the stream when a network refuses to let two peers talk directly, which is most corporate networks and a good share of mobile ones.

That is why included relay, rather than a video-minutes figure, is what separates the tiers: $49/mo for Pro, $199/mo for Business. Minutes would be a number we could quote and you could not verify. Relay is a number we pay for too.