Editing Alice and Bob (section)

===Cryptographic systems===
{{More citations needed section|date=May 2023}} 
The most common characters are Alice and Bob. Eve, Mallory, and Trent are also common names, and have fairly well-established "personalities" (or functions). The names often use alliterative mnemonics (for example, Eve, "eavesdropper"; Mallory, "malicious") where different players have different motives. Other names are much less common and more flexible in use. Sometimes the genders are alternated: Alice, Bob, Carol, Dave, Eve, etc.<ref>{{cite journal|last1=Xue|first1=Peng|last2=Wang|first2=Kunkun|last3=Wang|first3=Xiaoping|title=Efficient multiuser quantum cryptography network based on entanglement|journal=Scientific Reports|volume=7|issue=1|year=2017|page=45928|issn=2045-2322|doi=10.1038/srep45928|pmid=28374854|pmc=5379677|bibcode=2017NatSR...745928X|doi-access=free}} An example from quantum cryptography with Alice, Bob, Carol, and David.</ref>

{| class="wikitable"
|-
| ''Alice'' and ''Bob''
| The original, generic characters. Generally, Alice and Bob want to exchange a message or cryptographic key.
|-
| ''Carol'', ''Carlos'' or ''Charlie''
| A generic third participant.
|-
| ''Chuck'' or ''Chad''
| A third participant, usually of malicious intent.<ref>{{cite book |last=Tanenbaum |first=Andrew S. |title=Distributed Systems: Principles and Paradigms |isbn=978-0-13-239227-3 | publisher=[[Pearson Prentice Hall]] |year=2007 |url=https://books.google.com/books?id=DL8ZAQAAIAAJ |page=171;399&ndash;402 }}</ref>
|-
| ''Craig''
| A ''[[password cracking|password cracker]],'' often encountered in situations with stored passwords.
|-
| ''Dan'', ''Dave'' or ''David'' || A generic fourth participant.
|-
| ''Erin''
| A generic fifth participant, but rarely used, as "E" is usually reserved for Eve.
|-
| {{Anchor|Eve}}''Eve'' or ''Yves''
| An ''[[Eavesdropping|eavesdropper]]'', who is usually a passive attacker. While they can listen in on messages between Alice and Bob, they cannot modify them. In [[quantum cryptography]], Eve may also represent the ''environment''.{{clarify|date=November 2018}}
|-
| ''Faythe''
| A ''trusted [[Adviser|advisor]]'', courier or intermediary. Faythe is used infrequently, and is associated with ''faith'' and ''faithfulness''. Faythe may be a repository of key service or courier of shared secrets.{{citation needed|date=March 2016}}
|-
| ''Frank''
| A generic sixth participant.
|-
| ''Grace''
| A ''government representative''. For example, Grace may try to force Alice or Bob to implement backdoors in their protocols. Grace may also deliberately weaken standards.<ref>{{cite arXiv |eprint=2003.11511 |last1=Cho |first1=Hyunghoon |last2=Ippolito |first2=Daphne |author3=Yun William Yu |title=Contact Tracing Mobile Apps for COVID-19: Privacy Considerations and Related Trade-offs |year=2020 |class=cs.CR }}</ref>
|-
| ''Heidi''
| A ''mischievous designer'' for cryptographic standards, but rarely used.<ref>{{Cite book |last1=Fried |first1=Joshua |last2=Gaudry |first2=Pierrick |last3=Heninger |first3=Nadia |author3-link=Nadia Heninger |last4=Thomé |first4=Emmanuel |title=Advances in Cryptology – EUROCRYPT 2017 |chapter=A Kilobit Hidden SNFS Discrete Logarithm Computation |url=https://eprint.iacr.org/2016/961.pdf |publisher=University of Pennsylvania and INRIA, CNRS, University of Lorraine |series=Lecture Notes in Computer Science |date=2017 |volume=10,210 |pages=202–231 |doi=10.1007/978-3-319-56620-7_8 |arxiv=1610.02874 |isbn=978-3-319-56619-1 |s2cid=12341745 |access-date=2016-10-12}}</ref>
|-
| ''Ivan''
| An ''issuer'', mentioned first by Ian Grigg in the context of [[Ricardian contract]]s.<ref>{{Cite web|last=Grigg|first=Ian|title=Ivan The Honourable|url=http://iang.org/rants/ivan_the_honourable.html| website=iang.org | date=2002-11-24}}</ref>
|-
| ''Judy''
| A ''judge'' who may be called upon to resolve a potential dispute between participants. See [[Judge Judy]].
|-
| {{Anchor|Mallory}}{{Anchor|Mallet}}{{Anchor|Trudy}}''Mallory''<ref name="Schneier1996" /><ref>{{cite journal |last=Szabo |first=Nick |author-link=Nick Szabo |date=September 1997 |title=Formalizing and Securing Relationships on Public Networks |url=http://firstmonday.org/ojs/index.php/fm/article/view/548/469 |journal=First Monday|volume=2 |issue=9 |doi=10.5210/fm.v2i9.548|s2cid=33773111 |doi-access=free }}</ref><ref>{{citation |last=Schneier|first=Bruce |author-link=Bruce Schneier |title=Who are Alice & Bob? |date=2010-09-23 |url=https://www.youtube.com/watch?v=BuUSi_QvFLY  |archive-url=https://ghostarchive.org/varchive/youtube/20211222/BuUSi_QvFLY |archive-date=2021-12-22 |url-status=live|access-date=2017-05-02 |website=YouTube}}{{cbignore}}</ref> or (less commonly) ''Mallet''<ref name=Schneier1994/><ref name=Perkins2000/><ref name=LaMacchia2002/><ref name=Dolev2009/> or ''Darth''<ref name=Stallings1998/>
| A ''malicious attacker''. Associated with Trudy, an ''intruder''. Unlike the passive Eve, Mallory is an active attacker (often used in [[man-in-the-middle attack]]s), who can modify messages, substitute messages, or replay old messages. The difficulty of securing a system against a Mallory is much greater than against an Eve.
|-
| ''Michael'' or ''Mike''
| Used as an alternative to the eavesdropper Eve, from ''[[microphone]]''.
|-
| ''Niaj''
| Used as an alternative to the eavesdropper Eve in several South Asian nations.<ref>{{Cite web|title=A Collaborative Access Control Framework for Online Social Networks|url=http://raulpardo.net/papers/JLAMP2020.pdf}}</ref>
|-
| ''Olivia''
| An ''[[Oracle machine|oracle]]'', who responds to queries from other participants. Olivia often acts as a "[[black box]]" with some concealed state or information, or as a [[random oracle]].
|-
| ''Oscar''
| An ''opponent'', similar to Mallory, but not necessarily malicious.
|-
| ''Peggy'' or ''Pat''
| A ''prover'', who interacts with the ''verifier'' to show that the intended transaction has actually taken place. Peggy is often found in [[zero-knowledge proof]]s. 
|-
| ''Rupert''
| A ''repudiator'' who appears for interactions that desire [[non-repudiation]].
|-
|-
| ''Sybil''
| A ''[[pseudonym]]ous attacker'', who usually uses a large number of identities. For example, Sybil may attempt to subvert a [[reputation system]]. See [[Sybil attack]]. 
|-
| ''Trent'' or ''Ted''
| A ''trusted [[arbitral tribunal|arbitrator]]'', who acts as a [[trusted third party|neutral third party]].
|-
| ''Trudy''
| An ''intruder''.
|-
| ''Victor''<ref name="Schneier1996" /> or ''Vanna''<ref>{{cite journal |year=1992 |title=Algebraic Methods for Interactive Proof Systems |journal=Journal of the ACM |volume=39 |issue=4 |pages=859–868 |doi=10.1145/146585.146605 |author-link=Carsten Lund |first=Carsten |last=Lund |display-authors=etal |citeseerx=10.1.1.41.9477|s2cid=207170996 }}</ref>
| ''A verifier'', who requires proof from the ''prover''.
|-
| ''Walter''
| A ''[[prison warden|warden]]'', who may guard Alice and Bob.
|-
| ''Wendy''
| A ''[[whistleblower]]'', who is an insider with privileged access capable of divulging information.
|}