The Quest to Replace Passwords

Passwords are protectors of digital identity.

How can we better understand and evaluate the real-world use of different web authentication schemes?

An interactive version of Bonneau et al.'s S&P 2012 paper.

Why Passwords?

On the Internet, no one knows who you are until you establish your identity. This is authentication, and the oldest method is by providing a secret phrase upon sign-in that only you know, a password.

There have been decades of technological growth since the early Internet. The entire world's knowledge is now at our fingertips, we can communicate with friends and family worldwide, and social influencers reach audiences of millions. But passwords haven't changed. At the end of the day, every person from young to old, novice to expert, needs to remember passwords as a basic skill for using the Internet. Why can't we do better?

Challengers exist: for example, password managers reduce the number of different words that need to be memorized and possibly improve password quality. To name a few others, people use biometric authentication, one-time email links, and physical tokens.

However, every alternative approach has at least one downside. Password managers demand inconvenient backup codes, one-time links require email access, and physical tokens get lost.

The Comparison

Passwords and 35 password-replacement schemes are compared in the matrix below, based on a full gamut of 25 benefits. Colors represent properties that are better or worse than the row currently highlighted. Click on any row to select it as the base of comparison.

Full benefitAlmost benefitNo benefitYou are currently comparing to Web passwords.ImprovementRegressionPropertiesCategoriesSchemesMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableWeb passwordsMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePassword managersFirefoxMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableLastPassMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableProxyURRSAMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableImpostorMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableFederatedOpenIDMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableMicrosoft PassportMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableFacebook ConnectMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableBrowserIDMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableOTP over emailMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableGraphicalPCCPMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePassGoMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableCognitiveGrIDsure (original)Memorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableWeinshallMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableHopper BlumMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableWord AssociationMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePaper tokensOTPWMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableS/KEYMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePIN+TANMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableVisual cryptoPassWindowMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableHardware tokensRSA SecurIDMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableYubikeyMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableIronkeyMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableCAP readerMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePicoMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePhone-basedPhoolproofMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableCrontoMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableMP-AuthMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableOTP over SMSMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableGoogle 2-StepMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableBiometricFingerprintMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableIrisMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableVoiceMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableRecoveryPersonal knowledgeMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkablePreference-basedMemorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkableSocial re-auth.Memorywise effortlessScalable for usersNothing to carryPhysically effortlessEasy to learnEfficient to useInfrequent errorsEasy recovery from lossAccessibleNegligible cost per userServer compatibleBrowser compatibleMatureNon-proprietaryResilient to physical observationResilient to targeted impersonationResilient to throttled guessingResilient to unthrottled guessingResilient to internal observationResilient to leaks from other verifiersResilient to phishingResilient to theftNo trusted third partyRequiring explicit consentUnlinkable

How to Read This

Each row of the table consists of a single authentication scheme that aims to replace or supplement passwords. They are grouped into broad categories. The authors of the source paper, as domain experts within their fields, qualitatively evaluate each of the properties that these schemes offer the end user, and their 25 criteria are shown in the columns of the table.

Note that the benefits of each scheme cannot simply be added up numerically, as some matter more than others contextually. As a qualitative evaluation, it has no direct numeric counterpart.

What next? Well, there's no one true solution to all of our authentication concerns. At least, the next time someone sings the praises of their favorite password replacement, you can link them here and give them far more information about benefits and drawbacks than they ever wanted. 😄

Made by Eric Zhang (@ekzhang1).