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X.509

In cryptography, X.509 is an International Telecommunication Union (ITU) standard defining the format of public key certificates. X.509 certificates are used in many Internet protocols, including TLS/SSL, which is the basis for HTTPS, the secure protocol for browsing the web. They are also used in offline applications, like electronic signatures.

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Base standards
ASN.1
Committee
ITU-T Study Group 17
Domain
Cryptography
First published
1.0 at November 25, 1988; 37 years ago (1988-11-25)
Latest version
9.2 October 29, 2023; 2 years ago (2023-10-29)
Organization
ITU-T

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Overview

History and usage

Certificates

Sample X.509 certificates

Security

PKIX Working Group

Major protocols and standards using X.509 certificates

Advanced semantic analysis

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Map overview Semantic statistics

X.509

Nodes127
Edges126
Triples252
Avg. degree1.98
Density0.015748
Components1

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X.509

Top relations

related to Certificate filename extensions · 46
X.509 → Base64, Base64-encoded, BEGIN CERTIFICATE REQUEST, BEGIN CERTIFICATE-----and-----END CERTIFICATE, BEGIN ENCRYPTED PRIVATE KEY-----and, BEGIN PKCS7, BEGIN PRIVATE KEY, BER, CA, CA's, Certificate Authorities, Certificate Revocation List, CN, Common Name, Contains, CRL, CRLs, CSR, Defined, DER
related to Cryptographic weaknesses · 27
X.509 → Alexander Sotirov, Arjen Lenstra, Australian Researchers, Automatic Differential Path Searching, Because, Benne, CA, CA-provided, Certificate Authority, Chaos Communication Congress, Digital, Eurocrypt Conference, In, In April, In February, Macquarie University, Marc Stevens, MD2-based, MD5, RapidSSL
related to Architectural weaknesses · 25
X.509 → Adam Langley, Aggregation, Ambiguous OCSP, CAs, Certificate, CRL, CRLs, Delegation, EV, Extended Validation, Federation, Google, Identity, If, Internet, Issuance, OCSP, Path, PKI, Revocation
related to External links · 23
X.509 → Archived, Certificate Revocation List, Certification Path Building, CRL, Crypto FAQ, December, Gutmann's, Informational, Internet, ITU-T's, Overview, PKIX, Profile, Proposed Standard, Public Key Infrastructure, Public Key Infrastructure Certificate, RFC, RSA Laboratories, RSA Labs, Secure
related to history · 20
X.509 → CAs, CRL, IETF's PKIX, IETF's Public-Key Infrastructure, In, Internet, It, July, Lock-gray-alt-2, Lock-green, Lock-red-alt-2, OpenPGP-like, PGP, PKIX, Public Key Infrastructure, RFC, The, This, Version, Wikisource-logo
related to Major protocols and standards using X.509 certificates · 16
X.509 → Any, EAP-TLS, Extensions, HTTPS, IMAP, IPsec, LDAP, POP, RFC, S/MIME, Secure Multipurpose Internet Mail, SMTP, TLS, TLS/SSL, WiFi, XMPP
related to Certificates · 15
X.509 → An, CA, Certificate Management Protocol, Certificate Signing Request, CMP, CSR, Distinguished Name, DN, In, Other CA, Root CA, SCEP, Simple Certificate Enrollment Protocol, The, The CSR
related to PKI standards for X.509 · 14
X.509 → CA, Certification Path Building, CRL, Cryptographic Message Syntax Standard, Internet, OCSP, Online Certificate Status Protocol, Personal Information Exchange Syntax, PKCS7, PKI, SSL, Standard, TLS, Transport Layer Security
related to Sample X.509 certificates · 14
X.509 → DNS, ECDSA, GlobalSign, GlobalSign's RSA, Info, Issuer, It, Its Subject, SAN, Subject Alternative Name, The, The Subject Public Key, This, Wikipedia
related to Implementation issues · 13
X.509 → Black OPs, CA, Chaos Communication Congress, CN, CSR, Dan Kaminsky, Implementations, Many, OID, OIDs, PKI, Seen, Some

Important terminology Word statistics

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Important terminology

certificate certificates ca 509 key public using used validation use rfc pki like signed example authority subject signature end-entity intermediate

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
X.509Base standardsASN.11.00infobox
X.509CommitteeITU-T Study Group 171.00infobox
X.509DomainCryptography1.00infobox
X.509First published1.0 at November 25, 1988; 37 years ago (1988-11-25)1.00infobox
X.509Latest version9.2 October 29, 2023; 2 years ago (2023-10-29)1.00infobox
X.509OrganizationITU-T1.00infobox
X.509Related standardsISO/IEC 9594-8:2020, X.5001.00infobox
X.509SeriesX1.00infobox
X.509StatusIn force (Recommendation)1.00infobox
X.509Websitewww.itu.int/rec/T-REC-X.5091.00infobox
X.509is aInternational Telecommunication Union0.90text
Internet Explorerinstance ofBrowsers0.80text

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