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Best Practices for Voice Authentication. Charles R. Jankowski Jr., Ph. D. SpeechTek West 2007 February 21, 2007. Design for Voice Authentication. Dialog design is the single most critical aspect of voice authentication performance. Make Verifier SECURE. Make Verifier EASY to use.
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Best Practices for Voice Authentication Charles R. Jankowski Jr., Ph. D. SpeechTek West 2007 February 21, 2007
Design for Voice Authentication Dialog design is the single most critical aspect of voice authentication performance
Make Verifier SECURE • Make Verifier EASY to use Verifier Dialog and Application Design
Verifier Performance Measures Automation Rate • Percentage of repeat true speakers automated by system • 100 – False Reject Rate • Security Rate • 100 – False Accept Rate
Existing ID/Authentication SSN/Account# PIN
Enrollment SSN/Account# PIN 1-9 1-9 1-9 KV selection Optional Used by Verifier
Verification SSN/Account# 1-9 1-9 KV Optional Used by Verifier
Summary of design takeaways • Maintain consistency between enrollment and verification dialogs • Collect enough data during enrollment and verification • Use variable length verification • Use knowledge verification • Use speaker adaptation
Only using 1-9 for voiceprint creation and checking Could also use account number, phone number, etc… Maintain consistency between enrollment and verification SSN/Account# SSN/Account# Authentication 1-9 1-9 1-9 1-9 KV 1-9 KV selection
Choice of Verification Utterance • Why use identity claim? • One shorter dialog step • 80% of users claim and verify in one step • Why use common? • Many users do not like to speak their identity claim in public • Identity theft • Allow option to touch-tone identity claim • Multiple options for Identification • Enrollment very complex and long • Common utterance performance more predictable • Out-of-the-box performance better understood • ID claim may vary in length • Evaluating performance with identity claim more complex • Impostors MUST speak same text as enrollee • Identity claim -> Need live impostors
3 Enrollment utterances instead of 2: 1-3% lower automation 1 Verification utterance instead of 2: 1-3% lower automation 2. Collect enough data during enrollment and verification SSN/Account# SSN/Account# Authentication 1-9 1-9 1-9 1-9 KV 1-9 KV selection
Same verification performance as with 2 required utterances 3. Use variable length verification SSN/Account# SSN/Account# Authentication 1-9 80% 1-9 1-9 10% 1-9 1-9 KV selection
Examples: PIN, Secret Date Verifier not turned on Increases Automation Increases Effectiveness of Adaptation KV 10% 4. Use knowledge verification SSN/Account# SSN/Account# Authentication 1-9 80% 1-9 1-9 10% 1-9 1-9 KV selection
5. Use speaker adaptation SSN/Account# SSN/Account# Authentication 1-9 1-9 1-9 1-9 KV 1-9 KV selection
Speaker Verification Performance • Speaker Adaptation • Online: Score very well, adapt and get even better • Manual: Unsure, backoff to knowledge, adapt if knowledge passes • Cross-channel
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