[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-1-en-105":3,"doc-seo-571781-105":53,"doc-detail-571781-en":126},{"code":4,"msg":5,"data":6},0,"success",[7,14,19,24,29,34,39,44,49],{"id":8,"doc_module":9,"doc_module_name":10,"category_name":11,"show_sort_weight":12,"slug":13},11,1,"Template","Presentations",90,"presentations",{"id":15,"doc_module":9,"doc_module_name":10,"category_name":16,"show_sort_weight":17,"slug":18},12,"Resumes",80,"resumes",{"id":20,"doc_module":9,"doc_module_name":10,"category_name":21,"show_sort_weight":22,"slug":23},14,"Invoices",70,"invoices",{"id":25,"doc_module":9,"doc_module_name":10,"category_name":26,"show_sort_weight":27,"slug":28},15,"Posters",60,"posters",{"id":30,"doc_module":9,"doc_module_name":10,"category_name":31,"show_sort_weight":32,"slug":33},16,"Social Media",50,"social-media",{"id":35,"doc_module":9,"doc_module_name":10,"category_name":36,"show_sort_weight":37,"slug":38},17,"Forms",40,"forms",{"id":40,"doc_module":9,"doc_module_name":10,"category_name":41,"show_sort_weight":42,"slug":43},18,"Letters",30,"letters",{"id":45,"doc_module":9,"doc_module_name":10,"category_name":46,"show_sort_weight":47,"slug":48},21,"Paper Templates",5,"papers-templates",{"id":50,"doc_module":9,"doc_module_name":10,"category_name":51,"show_sort_weight":4,"slug":52},158,"General","general-158",{"code":4,"msg":54,"data":55},"ok",{"site_id":56,"language":57,"slug":58,"title":59,"keywords":60,"description":61,"schema_data":62,"social_meta":119,"head_meta":121,"extra_data":123,"updated_unix":125},105,"en","passwords-and-cryptwords-the-final-limits-on-lengths","Passwords and Cryptwords - The Final Limits on Lengths","","Computers advance faster than human memory, creating pressure to design authentication and cryptographic systems that keep password-like secrets usable at fixed length. The work distinguishes online-attack authentication passwords from offline-attack cryptwords used to generate encryption keys. It shows cryptwords can remain the same length by updating password key derivation function parameters and regenerating derived keys, and provides equations for minimal safe lengths under user threat models and for estimating attacker costs.",{"@graph":63,"@context":118},[64,80,101],{"@type":65,"itemListElement":66},"BreadcrumbList",[67,71,74,77],{"item":68,"name":69,"@type":70,"position":9},"https://docshare.wps.com","Home","ListItem",{"item":72,"name":10,"@type":70,"position":73},"https://docshare.wps.com/template/",2,{"item":75,"name":11,"@type":70,"position":76},"https://docshare.wps.com/template/presentations/",3,{"item":78,"name":59,"@type":70,"position":79},"https://docshare.wps.com/template/passwords-and-cryptwords-the-final-limits-on-lengths/571781/",4,{"url":78,"name":59,"@type":81,"image":82,"author":87,"headline":59,"publisher":90,"fileFormat":93,"inLanguage":57,"description":61,"dateModified":94,"datePublished":95,"encodingFormat":93,"isAccessibleForFree":96,"interactionStatistic":97},"DigitalDocument",{"url":83,"@type":84,"width":85,"height":86},"https://docshare.wps.com/thumbnails/passwords-and-cryptwords-the-final-limits-on-lengths/571781.png","ImageObject",442,249,{"name":88,"@type":89},"hdkawk","Person",{"url":68,"name":91,"@type":92},"DocShare","Organization","application/pdf","2026-10-20","2026-10-13",true,{"@type":98,"interactionType":99,"userInteractionCount":47},"InteractionCounter",{"@type":100},"ViewAction",{"@type":102,"mainEntity":103},"FAQPage",[104,110,114],{"name":105,"@type":106,"acceptedAnswer":107},"What is the difference between authentication passwords and cryptwords?","Question",{"text":108,"@type":109},"Authentication passwords mainly defend against online attacks, while cryptwords defend against offline attacks because they are used to generate cryptographic keys for encryption.","Answer",{"name":111,"@type":106,"acceptedAnswer":112},"How can cryptwords remain the same length as computers get faster?",{"text":113,"@type":109},"By using password key derivation functions with periodically updated parameters, then regenerating the derived key from the cryptword so security strength is maintained despite computation advances.",{"name":115,"@type":106,"acceptedAnswer":116},"How are minimal password and cryptword lengths determined in this work?",{"text":117,"@type":109},"The paper provides simple equations that end users and system administrators can apply using personal threat models, including methods to estimate attacker costs with cloud computing capabilities.","https://schema.org",{"og:url":78,"og:type":120,"og:title":59,"og:site_name":91,"og:description":61},"article",{"robots":122,"canonical":78},"index,follow",{"doc_id":124,"site_id":56},571781,1792016343,{"code":4,"msg":5,"data":127},{"doc_id":124,"user_id":128,"nickname":88,"user_avatar":129,"doc_module":9,"category_id":8,"category_name":11,"doc_title":59,"doc_description":61,"doc_content":130,"file_id":131,"file_url":132,"file_type":133,"file_size":134,"view_count":47,"is_deleted":4,"is_public":9,"is_downloadable":9,"audit_status":9,"page_count":25,"language":135,"language_code":57,"site_id":56,"html_lang":57,"table_of_contents":136,"faqs":137,"seo_title":138,"seo_description":61,"update_tm":139,"read_time":47},3985747859855,"https://ap-avatar.wpscdn.com/davatar_276721f389ce27ea32af1340a28f341c","Passwords and Cryptwords  \nThe Final Limits on Lengths  \nMichael Clark Brigham Young University  \nProvo, UT, USA [clark.michael.c@gmail.com](clark.michael.c@gmail.com)  \nKent Seamons  \nBrigham Young University Provo, UT, USA [seamons@cs.byu.edu](seamons@cs.byu.edu)  \nABSTRACT  \nComputers get faster every year; brains don’t. Passwords and other memorized credentials have unique usability advantages over tokens and biometrics, so we desire to design secure systems that maintain lengths that users can memorize. Some passwords are subject primarily to online attacks, and are simple to defend with rate limits and lockouts. Others, used to generate encryption keys, must be secure against offline attacks. We coin the term łcryptwordž to distinguish these from passwords subject primarily to online attacks.  \nAuthentication passwords do not need to get longer as computers get faster, if protected by rate limits and lockouts. Using password key derivation functions (pwKDFs) Ð a class of preexisting cryptographic algorithms Ð we show that cryptwords can also remain the same length and maintain their security strength despite advancesin computation. We achieve this by regularly updating the pwKDF parameters and regenerating the derived key from the cryptword. In cases where it is not possible to meaningfully regenerate the derived key, such as archival data or public verifiers, cryptword lengths should be chosen to last the lifetime of the data.  \nWe provide simple equations that end users and system administrators can use to determine minimal assigned password and cryptword lengths based on personal threat models. We also show how to use the capabilities of cloud computing providers to estimate attacker costs. These same equations give a timeframe for cryptword and secret rotation once the encrypted data leaks. Because these equations do not rely on the current date or current hardware capabilities, they show that if regularly used, password and cryptword lengths can remain constant despite improvements in hardware.  \nCCS CONCEPTS  \n· Security and privacy →Authentication;Usability in security and privacy; Key management.  \nKEYWORDS  \npasswords, cryptwords, authentication  \nACM Reference Format:  \nMichael Clark and Kent Seamons. 2022. Passwords and Cryptwords: The Final Limits on Lengths. In New Security Paradigms Workshop (NSPW’22),  \nNSPW’22, October 24ś27, 2022, North Conway, NH, USA  \n© 2022 Copyright held by the owner/author(s) . Publication rights licensed to ACM. This is the author’s version of the work. It is posted here for your personal use. Not for redistribution. The definitive Version of Record was published in New Security Paradigms Workshop (NSPW’22), October 24ś27, 2022, North Conway, NH, USA, [https:](https:)//[doi.org/10.1145/3584318.3584324](doi.org/10.1145/3584318.3584324) .  \nOctober 24ś27, 2022, North Conway, NH, USA. ACM, New York, NY, USA, 15 pages. [https://doi.org/10.1145/3584318.3584324](https://doi.org/10.1145/3584318.3584324)  \n1 INTRODUCTION  \nThere are two kinds of passwords Ð those that secure against online attacks and are suitable for authentication, and those that secure against offline attacks and are suitable for encrypting data [29] . For this second kind we coin the term cryptword (see Section 6.2) to distinguish them from passwords that enable you to authenticate to another party (łpassž) . Figure 1 highlights some key differences in purpose, attack types, and sufficient entropy between authentication password and cryptwords.  \nPasswords  \n|  | Authentication Passwords | Cryptwords |\n| --- | --- | --- |\n| Purpose | Authentication | Encryption |\n| Attacks | Online | Offline |\n| Entropy | 13ś47 bits | Typically > 48 bits |\n\nFigure 1: Two Kinds of Passwords  \nUsers often pick their own passwords via an internal process. An assigned password is any password the user accepts which they did not choose. A software system or organization may assign a password to a user or a user may generate a random passwo","cbCaidBNnq2qVwni","https://ap.wps.com/l/cbCaidBNnq2qVwni","pdf",287844,"English","# Abstract\n# Introduction\n## Two kinds of passwords: authentication vs cryptwords\n# Cryptword definition and applications\n## Data at rest\n## Data in use\n## Data in motion\n# Security approach and length limits","[{\"question\":\"What is the difference between authentication passwords and cryptwords?\",\"answer\":\"Authentication passwords mainly defend against online attacks, while cryptwords defend against offline attacks because they are used to generate cryptographic keys for encryption.\"},{\"question\":\"How can cryptwords remain the same length as computers get faster?\",\"answer\":\"By using password key derivation functions with periodically updated parameters, then regenerating the derived key from the cryptword so security strength is maintained despite computation advances.\"},{\"question\":\"How are minimal password and cryptword lengths determined in this work?\",\"answer\":\"The paper provides simple equations that end users and system administrators can apply using personal threat models, including methods to estimate attacker costs with cloud computing capabilities.\"}]","Passwords and Cryptwords - The Final Limits on Lengths | PDF",1791923695]