5. A method for verifying a spoken password comprising the steps of: storing a first speech model of a first entry of a password spoken by a user; storing a plurality of reference voice (RV) speech models based on speech inputs by persons, each RV speech model including said password; selecting at least one RV speech model based on a predetermined difference of similarity between said first speech model and said at least one RV speech model, said step of selecting comprising the step of ascertaining a similarity score for each RV speech model by comparing said first speech model with each of said RV speech models; storing a second speech model of a second entry of said password spoken by user; comparing said second speech model and said selected at least one RV model to determine a measure of similarity; determining validity of said second entry of said password based on said measure of similarity, said step of selecting said at least one RV speech model further comprising the step of ranking said RV speech models based on said similarity scores, and wherein said selecting step selects said at least one RV speech model based on a predetermined threshold from a range of said RV speech model rankings of 15-50 percentile, where a 100 percentile ranking represents a highest ranked RV speech model most similar to said first speech model.
5. A method for verifying a spoken password comprising the steps of: storing a first speech model of a first entry of a password spoken by a user; storing a plurality of reference voice (RV) speech models based on speech inputs by persons, each RV speech model including said password; selecting at least one RV speech model based on a predetermined difference of similarity between said first speech model and said at least one RV speech model, said step of selecting comprising the step of ascertaining a similarity score for each RV speech model by comparing said first speech model with each of said RV speech models; storing a second speech model of a second entry of said password spoken by user; comparing said second speech model and said selected at least one RV model to determine a measure of similarity; determining validity of said second entry of said password based on said measure of similarity, said step of selecting said at least one RV speech model further comprising the step of ranking said RV speech models based on said similarity scores, and wherein said selecting step selects said at least one RV speech model based on a predetermined threshold from a range of said RV speech model rankings of 15-50 percentile, where a 100 percentile ranking represents a highest ranked RV speech model most similar to said first speech model. 7. The spoken password verification method of claim 5 wherein said range of said RV speech model rankings consists of 20-40 percentile.