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T5 · T5-R15 · STIR and SHAKEN

Where the vendors put the same words

Two vendors use the words. Twilio has a trusted-calling title and an onboarding label. Bandwidth has an API sentence and a separate caller-name query for the US and Canada. CNAM and STIR are neighbors, not the same API. The caller-name service tells you a name. STIR tells you how strongly a provider asserts the number.

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Counts on this page

4boxes
5opened sources
2confirm rows
5study lines

Opened sources

Confirm rows, no URL

Learn it in 5 minutes

  • Twilio's voice docs include a page titled Trusted calling with SHAKEN/STIR, and the voice navigation lists SHAKEN/STIR overview and onboarding beside Voice Integrity.
  • Bandwidth's voice page says its STIR/SHAKEN APIs are for managing regulatory compliance, in the sentence that opened.
  • The same Bandwidth page says a per-query service provides the caller name on VoIP calls in the United States and Canada.
  • No attestation fee, no letter-to-price table, and no certificate bundle were read on those pages.
  • Caller ID spoofing remains the problem the Wikipedia article names. A vendor menu does not replace the A, B, and C definitions.

Visual

Where the vendors put the same words Vendors. Teaching sketch. Confirm a live system. Twilio Bandwidth CNAM A B C Names come from pages opened in 2026-10. A missing name stays confirm.

Count the boxes: 4. Each label is a name from a page or a study label marked on the drawing.

Flow

Where the vendors put the same words Caller SIP Called session setup session setup RTP, not required to hairpin Teaching sketch from RFC 3261 and RFC 3550. Not a packet capture.

What is going on

Two vendors use the words. Twilio has a trusted-calling title and an onboarding label. Bandwidth has an API sentence and a separate caller-name query for the US and Canada. CNAM and STIR are neighbors, not the same API. The caller-name service tells you a name. STIR tells you how strongly a provider asserts the number.

Because the Twilio page's body, in this session, was mostly the voice navigation, do not invent Twilio's onboarding clicks. The title opened. The click path stays confirm.

Worked example

On a worksheet, pair Bandwidth's caller-name query with CNAM, and pair both vendors' STIR words with the Wikipedia letters. Leave a blank column for fees.

Quiz

1. Bandwidth's voice page describes a caller-name query for VoIP calls in the US and Canada.

2. This room can price Twilio SHAKEN onboarding.

Ecosystem

Sister pieces sit on the ecosystem page: the glossary, the mind map, the integration map, and the bridges.

  • Voice Integrity — A Twilio voice-navigation label beside SHAKEN/STIR. This session did not open a separate definition page for it.
  • Caller-name query — The Bandwidth voice service for the calling name on VoIP calls in the US and Canada, distinct from the STIR/SHAKEN API sentence.

Config. Enable or test signing only in the portal you administer. Write down the attestation you observed, not the one you hoped for.

Troubleshooting. A displayed name can be present when attestation is C. Check the letter and the name as separate fields.

Bridge. The Identity header room explains the token. This room only records which vendor pages used the trademarked protocol name.

Mind map, sister technologies, and future hooks live on the ecosystem page.

Sources and go deeper

Opened 2026-10. A row marked confirm has no link, because that page was not verified.

  • Twilio. Trusted calling with SHAKEN/STIR last checked 2026-10
  • Twilio. Programmable Voice last checked 2026-10
  • Bandwidth. Bandwidth Voice last checked 2026-10
  • Wikipedia. STIR/SHAKEN last checked 2026-10
  • Wikipedia. Caller ID last checked 2026-10
  • Confirm. Twilio SHAKEN onboarding steps and any signing fee. confirm. last checked 2026-10
  • Confirm. Bandwidth STIR API parameters. confirm. The voice page named the APIs and did not list the fields. last checked 2026-10

sources.json Markdown