Describe the core features of a conventional biometric system.

What will be an ideal response?

Biometric capture module: A fingerprint reader or iris scanner.
Feature extraction module: Software that selects the active matching data and produces a feature vector of the biometric; features extracted from the biometric reading will be used to create the feature vector.
Matching module: Compares the captured biometric with an existing database; measurements extracted from the active matching data describe the useful image features and thus are known as a feature vector.
Decision module: Provides a degree of confidence in any identity matched against the person providing the biometric sample.