GlossaryDEFINED TERM / SAFETY-NUMBER

Safety number

A comparison value derived from identity keys for independent verification of a peer.

Working definition

A safety number or QR comparison can help detect an unnoticed replacement of identity keys. Verification must use a sufficiently independent channel.

When devices or keys change, the application should explain why the value changed and what action is required. Warnings without a decision path are quickly ignored.

Three verification questions

  1. 01Which keys contribute to the value?
  2. 02How is a change explained?
  3. 03Is there an independent verification channel?