challenge-response
Query then verify
Challenge-response describes a security mechanism where one party issues a challenge and the other must provide the correct response to prove identity or authorization.
The pattern appears in computer authentication, cryptographic protocols, and access control systems: The server sends a random number, and the client must return the correct hash.
CAPTCHAs are a common example—proving you're human by solving a puzzle the challenger presents.
Prescribed conduct rules
- verificationProving something accurate
- tokenRepresentative placeholder
- handshakeMutual palm-gripping gesture
- noncePresent purpose or occasion
cryptographic · digest · credential · session · login · password · hash · server
Network access control system
- intrusionUnauthorized entry into space
- biometricMeasuring unique physical characteristics
- smartcardEmbedded-chip plastic credential
- RSAPublic-key encryption algorithm
OTP · encryption · decryption · brute-force · zero-knowledge · proof · attestation · tamper-proof
protocol
Prescribed conduct rules
- verificationProving something accurate
- tokenRepresentative placeholder
- handshakeMutual palm-gripping gesture
nonce · cryptographic · digest · credential · session · login · password · hash · server · client
firewall
Network access control system
- intrusionUnauthorized entry into space
- biometricMeasuring unique physical characteristics
- smartcardEmbedded-chip plastic credential
RSA · OTP · encryption · decryption · brute-force · zero-knowledge · proof · attestation · tamper-proof
stimulus
What prompts a reaction
- reactionResponse to stimulus
- conditionedTaught automatic responses
- reflexInvoluntary stimulus response
trigger · automatic · learned · Pavlovian · adaptive · instinctive · feedback · cue · prompt · elicit
antiphon
Alternating liturgical song
- litanyProlonged repetitive account
- versicleShort liturgical sentence
- congregationalOf member-governed worship communities
chant · psalm · cantor · choir · recitation · prayer · amen · alleluia · dialogue · worship
challenge-responsebiometric authentication
Identity verification via body traits
challenge-responsefire-and-forget
Requires no post-launch input
broadcast · push notification · store-and-forward · streaming
challenge, response, challenges, challenged, challenging, challenger, challengers, respond, responds