Share to: share facebook share twitter share wa share telegram print page

Key (cryptography)

A key in cryptography is a piece of information, usually a string of numbers or letters that are stored in a file, which, when processed through a cryptographic algorithm, can encode or decode cryptographic data. Based on the used method, the key can be different sizes and varieties, but in all cases, the strength of the encryption relies on the security of the key being maintained. A key's security strength is dependent on its algorithm, the size of the key, the generation of the key, and the process of key exchange.

Scope

The key is what is used to encrypt data from plaintext to ciphertext.[1] There are different methods for utilizing keys and encryption.

Symmetric cryptography

Symmetric cryptography refers to the practice of the same key being used for both encryption and decryption.[2]

Asymmetric cryptography

Asymmetric cryptography has separate keys for encrypting and decrypting.[3][4] These keys are known as the public and private keys, respectively.[5]

Purpose

Since the key protects the confidentiality and integrity of the system, it is important to be kept secret from unauthorized parties. With public key cryptography, only the private key must be kept secret, but with symmetric cryptography, it is important to maintain the confidentiality of the key. Kerckhoff's principle states that the entire security of the cryptographic system relies on the secrecy of the key.[6]

Key sizes

Key size is the number of bits in the key defined by the algorithm. This size defines the upper bound of the cryptographic algorithm's security.[7] The larger the key size, the longer it will take before the key is compromised by a brute force attack. Since perfect secrecy is not feasible for key algorithms, researches are now more focused on computational security.

In the past, keys were required to be a minimum of 40 bits in length, however, as technology advanced, these keys were being broken quicker and quicker. As a response, restrictions on symmetric keys were enhanced to be greater in size.

Currently, 2048 bit RSA[8] is commonly used, which is sufficient for current systems. However, current key sizes would all be cracked quickly with a powerful quantum computer.

“The keys used in public key cryptography have some mathematical structure. For example, public keys used in the RSA system are the product of two prime numbers. Thus public key systems require longer key lengths than symmetric systems for an equivalent level of security. 3072 bits is the suggested key length for systems based on factoring and integer discrete logarithms which aim to have security equivalent to a 128 bit symmetric cipher.”[9]

Key generation

To prevent a key from being guessed, keys need to be generated randomly and contain sufficient entropy. The problem of how to safely generate random keys is difficult and has been addressed in many ways by various cryptographic systems. A key can directly be generated by using the output of a Random Bit Generator (RBG), a system that generates a sequence of unpredictable and unbiased bits.[10] A RBG can be used to directly produce either a symmetric key or the random output for an asymmetric key pair generation. Alternatively, a key can also be indirectly created during a key-agreement transaction, from another key or from a password.[11]

Some operating systems include tools for "collecting" entropy from the timing of unpredictable operations such as disk drive head movements. For the production of small amounts of keying material, ordinary dice provide a good source of high-quality randomness.

Establishment scheme

The security of a key is dependent on how a key is exchanged between parties. Establishing a secured communication channel is necessary so that outsiders cannot obtain the key. A key establishment scheme (or key exchange) is used to transfer an encryption key among entities. Key agreement and key transport are the two types of a key exchange scheme that are used to be  remotely exchanged between entities . In a key agreement scheme, a secret key, which is used between the sender and the receiver to encrypt and decrypt information, is set up to be sent indirectly. All parties exchange information (the shared secret) that permits each party to derive the secret key material. In a key transport scheme, encrypted keying material that is chosen by the sender is transported to the receiver. Either symmetric key or asymmetric key techniques can be used in both schemes.[11]

The Diffie–Hellman key exchange and Rivest-Shamir-Adleman (RSA) are the most two widely used key exchange algorithms.[12] In 1976, Whitfield Diffie and Martin Hellman constructed the Diffie–Hellman algorithm, which was the first public key algorithm. The Diffie–Hellman key exchange protocol allows key exchange over an insecure channel by electronically generating a shared key between two parties. On the other hand, RSA is a form of the asymmetric key system which consists of three steps: key generation, encryption, and decryption.[12]

Key confirmation delivers an assurance between the key confirmation recipient and provider that the shared keying materials are correct and established. The National Institute of Standards and Technology recommends key confirmation to be integrated into a key establishment scheme to validate its implementations.[11]

Management

Key management concerns the generation, establishment, storage, usage and replacement of cryptographic keys. A key management system (KMS) typically includes three steps of establishing, storing and using keys. The base of security for the generation, storage, distribution, use and destruction of keys depends on successful key management protocols.[13]

Key vs password

A password is a memorized series of characters including letters, digits, and other special symbols that are used to verify identity. It is often produced by a human user or a password management software to protect personal and sensitive information or generate cryptographic keys. Passwords are often created to be memorized by users and may contain non-random information such as dictionary words.[11] On the other hand, a key can help strengthen password protection by implementing a cryptographic algorithm which is difficult to guess or replace the password altogether. A key is generated based on random or pseudo-random data and can often be unreadable to humans.[14]

A password is less safe than a cryptographic key due to its low entropy, randomness, and human-readable properties. However, the password may be the only secret data that is accessible to the cryptographic algorithm for information security in some applications such as securing information in storage devices. Thus, a deterministic algorithm called a key derivation function (KDF) uses a password to generate the secure cryptographic keying material to compensate for the password's weakness. Various methods such as adding a salt or key stretching may be used in the generation.[11]

See also

References

  1. ^ Piper, Fred (2002), "Cryptography", Encyclopedia of Software Engineering, American Cancer Society, doi:10.1002/0471028959.sof070, ISBN 978-0-471-02895-6, retrieved 2021-04-09
  2. ^ "What is a cryptographic key? | Keys and SSL encryption".
  3. ^ "Asymmetric-Key Cryptography". www.cs.cornell.edu. Retrieved 2021-04-02.
  4. ^ Chandra, S.; Paira, S.; Alam, S. S.; Sanyal, G. (2014). "A comparative survey of Symmetric and Asymmetric Key Cryptography". 2014 International Conference on Electronics, Communication and Computational Engineering (ICECCE). pp. 83–93. doi:10.1109/ICECCE.2014.7086640. ISBN 978-1-4799-5748-4. S2CID 377667.
  5. ^ Kumar, M. G. V.; Ragupathy, U. S. (March 2016). "A Survey on current key issues and status in cryptography". 2016 International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET). pp. 205–210. doi:10.1109/WiSPNET.2016.7566121. ISBN 978-1-4673-9338-6. S2CID 14794991.
  6. ^ Mrdovic, S.; Perunicic, B. (September 2008). "Kerckhoffs' principle for intrusion detection". Networks 2008 - the 13th International Telecommunications Network Strategy and Planning Symposium. Vol. Supplement. pp. 1–8. doi:10.1109/NETWKS.2008.6231360. ISBN 978-963-8111-68-5.
  7. ^ "What is Key Length? - Definition from Techopedia". Techopedia.com. 16 November 2011. Retrieved 2021-05-01.
  8. ^ Hellman, Martin. "An Overview of Public Key Cryptography" (PDF). IEEE Communications Magazine.
  9. ^ "Anatomy of a change – Google announces it will double its SSL key sizes". Naked Security. 2013-05-27. Retrieved 2021-04-09.
  10. ^ Dang, Quynh (August 2012). "Recommendation for Applications Using Approved Hash Algorithms" (PDF). Retrieved 2021-04-02.
  11. ^ a b c d e Turan, M. S.; Barker, E. B.; Burr, W. E.; Chen, L. (2010). "Recommendation for password-based key derivation" (PDF). doi:10.6028/NIST.SP.800-132. S2CID 56801929. {{cite journal}}: Cite journal requires |journal= (help)
  12. ^ a b Yassein, M. B.; Aljawarneh, S.; Qawasmeh, E.; Mardini, W.; Khamayseh, Y. (2017). "Comprehensive study of symmetric key and asymmetric key encryption algorithms". 2017 International Conference on Engineering and Technology (ICET). pp. 1–7. doi:10.1109/ICEngTechnol.2017.8308215. ISBN 978-1-5386-1949-0. S2CID 3781693.
  13. ^ Barker, Elaine (January 2016). "Recommendation for Key Management" (PDF). Retrieved 2021-04-02.
  14. ^ Khillar, Sagar (29 April 2020). "Difference Between Encryption and Password Protection | Difference Between". Retrieved 2021-04-02.

Baca informasi lainnya yang berhubungan dengan : article

Article 19 Article 20

Read other articles:

Vatican Miracle Examinerバチカン奇跡調査官(Bachikan Kiseki Chōsakan)GenreMisteri[1] Novel ringanPengarangRin FujikiIlustratorTHORES ShibamotoPenerbitKadokawa ShotenImprintHorror BunkoTerbit10 Desember 2007 – sekarangVolume13 (Daftar volume) MangaPengarangEiji KanedaPenerbitKadokawa ShotenMajalahComic KaiTerbit24 Januari 2012 – 24 Januari 2013Volume2 MangaPengarangAnjue HinoPenerbitMedia FactoryMajalahMonthly Comic GeneDemografiShōjoTerbit12 Agustus 2016 – sekarang Seri a…

Polish footballer Emilia Zdunek Personal informationDate of birth (1992-09-12) 12 September 1992 (age 31)[1]Place of birth Szczecin, Poland[2]Height 1.65 m (5 ft 5 in)Position(s) Midfielder[1]Team informationCurrent team Górnik ŁęcznaNumber 24Youth career2002–2007 UKS Victoria SP 2 SianówSenior career*Years Team Apps (Gls)2007–2008 UKS Victoria SP 2 Sianów 2[3] (1)2008–2013 Pogoń Women Szczecin 49[4] (23)2013 Unia Racibórz …

Evangelisches Kirchenzentrum Kronsberg (2010) Das Evangelische Kirchenzentrum Kronsberg ist ein Kirchenbau am Westhang des Kronsberges in Hannover, der zur St.-Johannis-Kirchengemeinde in Hannover-Bemerode gehört. Die Evangelisch-Freikirchliche Gemeinde Hannover-Kronsberg (Baptisten) nutzt seit 2005 die Räumlichkeiten für ihre Gottesdienste mit. Das Kirchenzentrum befindet sich am Hauptplatz (Thie) der Expo-Siedlung in Nachbarschaft mit dem Kommunalen Kultur- und Sozialzentrum KroKuS. Zum Gem…

  الجمعية الإنسانية الأميركية الجمعية الإنسانية الأميركية‌ الاختصار (بالإنجليزية: AHA)‏  البلد الولايات المتحدة  المقر الرئيسي واشنطن  تاريخ التأسيس 1941  مكان التأسيس الولايات المتحدة  الوضع القانوني منظمة 501(c)(3)  العضوية هيومانستس إنترناشيونال[1]  ال…

دين خارجي هو ذلك الجزء من الدين الكلي في البلاد التي هي المستحقة للدائنين خارج البلاد.[1][2][3] يمكن للمدينين تكون الحكومة أو الشركات أو المنازل الخاصة. الدين تتضمن الأموال المستحقة للمصارف التجارية الخاصة، وغيرها من الحكومات، أو المؤسسات المالية الدولية مثل صندو

Dindin WahyudinDindin Wahyudin, Kementerian Luar Negeri Republik IndonesiaDuta Besar Indonesia untuk Senegal ke-11PetahanaMulai menjabat 20 Oktober 2020PresidenJoko WidodoPendahuluMansyur Pangeran Informasi pribadiLahir30 September 1966 (umur 57) Bandung, IndonesiaOrang tuaH. Eman Sulaeman dan Hj Asiah HowariahAlma materUniversité Jean Moulin (Lyon III), Lyon, PerancisPekerjaanDiplomatSunting kotak info • L • B Drs. H. Dindin Wahyudin, DEA (lahir 30 September 1966) ad…

هذه المقالة يتيمة إذ تصل إليها مقالات أخرى قليلة جدًا. فضلًا، ساعد بإضافة وصلة إليها في مقالات متعلقة بها. (أبريل 2019) أوليفييه لي ماي   معلومات شخصية الميلاد 26 مايو 1734[1]  فالنسيان  الوفاة سنة 1797[1]  باريس  مواطنة فرنسا[2]  عضو في الأكاديمية الملكية للر

Ne doit pas être confondu avec Championnat d'URSS de football. Championnat de Russie féminin de football(ru) Чемпионат России по футболу среди женщин Généralités Sport Football Création 1992 Organisateur(s) RFS Périodicité Annuelle Nations Russie Participants 12 équipes Statut des participants Professionnel Site web officiel www.rfs.ru Hiérarchie Hiérarchie 1er niveau Palmarès Tenant du titre Zénith Saint-Pétersbourg (2023) Plus titré(s) Zve…

Someone imprisoned for their political activity Sahrawi activist Ali Salem Tamek.Aung San Suu KyiNelson MandelaEmma GoldmanMahatma Gandhi A political prisoner is someone imprisoned for their political activity. The political offense is not always the official reason for the prisoner's detention. There is no internationally recognized legal definition of the concept, although numerous similar definitions have been proposed by various organizations and scholars, and there is a general consensus am…

العلاقات اليابانية السلوفينية اليابان سلوفينيا   اليابان   سلوفينيا تعديل مصدري - تعديل   العلاقات اليابانية السلوفينية هي العلاقات الثنائية التي تجمع بين اليابان وسلوفينيا.[1][2][3][4][5] مقارنة بين البلدين هذه مقارنة عامة ومرجعية للدولتين: وج…

2007 live album by YuriVive la HistoriaLive album by YuriReleased2007 (Mexico)GenrePopConcertLabelEMIDirectorRodrigo EspinozaYuri chronology Acompáñame(2006) Vive la Historia(2007) Mi Hijita Linda(2008) Alternative coverSpecial Edition Vive la Historia (English: Live the history) is a live album by Mexican pop singer Yuri. It was released in 2007. It sold more than 100,000 earning Gold and Platinum disc.[1] Reception In 2007, Yuri released Vive la Historia that consisted of her…

Peta yang menunjukkan letak San Ildefonso Data sensus penduduk di San Ildefonso Tahun Populasi Persentase 199569.319—200079.9563.11%200793.4382.17% San Ildefonso adalah munisipalitas di provinsi Bulacan, Filipina. Pada tahun 2007, munisipalitas ini memiliki populasi sebesar 93.438 jiwa atau 15.753 rumah tangga. Pembagian wilayah Secara politis San Ildefonso terbagi atas 36 barangay, yaitu: Akle Alagao Anyatam Bagong Barrio Basuit Bubulong Munti Bubulong Malaki Buhol na Mangga Bulusukan Calasag…

State park in Will County, Illinois, US Des Plaines Fish and Wildlife AreaIUCN category IV (habitat/species management area)Map of the U.S. state of Illinois showing the location of Des Plaines Fish and Wildlife AreaShow map of IllinoisDes Plaines Fish and Wildlife Area (the United States)Show map of the United StatesLocationWill County, Illinois, USANearest cityWilmingtonCoordinates41°23′36″N 88°12′36″W / 41.39333°N 88.21000°W / 41.39333; -88.21000Area5,…

Печать Иллинойсаангл. Seal of Illinois Детали Утверждена 1868 год[1]  Медиафайлы на Викискладе Печать Иллинойса (англ. Seal of Illinois) — официальный символ штата Иллинойс, США. Содержание 1 История 2 Описание 3 См. также 4 Примечания 5 Ссылки История Первая печать штата была пр…

Collaboration and intimate relationships between French women and Nazi occupiers A woman's head is shaved as punishment for collaboration horizontale. Montélimar area, August 1944. Horizontal collaboration (French: Collaboration horizontale, collaboration féminine or collaboration sentimentale) referred to the romantic or sexual relationship many women in France had or allegedly had with members of the German occupation forces after the Fall of France in 1940. The existence of these liaisons h…

A military event in Ukrainian history at the end of World War I For other uses, see Death Triangle (disambiguation).You can help expand this article with text translated from the corresponding article in Ukrainian. Click [show] for important translation instructions. Machine translation, like DeepL or Google Translate, is a useful starting point for translations, but translators must revise errors as necessary and confirm that the translation is accurate, rather than simply copy-pasting machine-…

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Subodh College – news · newspapers · books · scholar · JSTOR (May 2018) (Learn how and when to remove this template message) S.S. Jain Subod P.G (Autonomous) College, JaipurTypePublicEstablished1954PrincipalK. B. SharmaLocationJaipur, Rajasthan, IndiaCampusUrbanAf…

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: The Terracotta Dog – news · newspapers · books · scholar · JSTOR (January 2021) (Learn how and when to remove this template message) The Terracotta Dog Italian first edition coverAuthorAndrea CamilleriOriginal titleIl cane di terracottaTranslatorStephen Sarta…

Australian journalist This article may rely excessively on sources too closely associated with the subject, potentially preventing the article from being verifiable and neutral. Please help improve it by replacing them with more appropriate citations to reliable, independent, third-party sources. (January 2014) (Learn how and when to remove this template message) Margo Kingston (born 1959) is an Australian journalist, author, and commentator. She is best known for her work at The Sydney Morning …

MojorenoDesaKantor Desa MojorenoNegara IndonesiaProvinsiJawa TengahKabupatenWonogiriKecamatanSidoharjoKode pos57682Kode Kemendagri33.12.14.2006 Luas... km²Jumlah penduduk... jiwaKepadatan... jiwa/km² Mojoreno adalah desa di kecamatan Sidoharjo, Kabupaten Wonogiri, provinsi Jawa Tengah, Indonesia. Pembagian Wilayah Desa ini terdiri dari 9 dusun: Cungkrung Pohgede Wates Kulon Wates Wetan Mojoreno Lor Mojoreno Kidul Kedungsono Lor Kedungsono Tengah Kedungsono Kidul Akses Desa Mojoreno berjar…

Kembali kehalaman sebelumnya