Original sentence: Biometrics are used to identify the identity of an input sample when compared to a template, used in cases to identify identity or specific objects by certain characteristics.Standard validation systems often use multiple inputs of samples for sufficient validation, such as particular characteristics of the sample.This intends to enhance security as multiple different samples are required such as security tags and codes and sample dimensions.knowledge-based the use of a code or password.possession-based: using one specific "token" such as a security tag or a card
Edited sentence: Even if we use the best encrypting algorithm, the whole security is based on the key.If it is lost, somebody else might use it to falsify his identity.If it is too short, it is simple to guess it or crack it making several attempts, but if it is too complicated it can't be remembered and the common user will keep it written somewhere, so it can be lost or stolen.Moreover biometric systems can be used in conjunction with passwords or tokens, thus improving the security of existing systems without replacing them.Nowadays identity verification is mainly performed in two ways:.Particular characteristics of the body or habits are much more complicated to forge than a string of text, even if it is very long.Reliability of biometric systems will be discussed later, but it is evident that using biometrics adds a complexity to identification systems that would be hard to reach with a standard password-based approach.The main advantages of biometrics over a standard system are:.The modern rapid advancements in networking, communication and mobility increased the need of reliable ways to verify the identity of any person.Those weaknesses of standard validation systems can be avoided if our own body becomes our key.biometric traits are relatively difficult to copy, share and distribute (passwords can be announced in crackers' websites).biometric traits cannot be forgotten or mislaid, and can be lost only through trauma (whereas passwords can be forgotten and tokens easily lost or mislaid).knowledge-based using a password.pace the previous point, biometric traits require the person being authenticated to be present at the time and point of authentication.possession-based: the whole security is based on a "token" the user has (such as a credit card or a document)