CA証明書
A digital certificate issued to a Certificate Authority, used to sign and validate other digital certificates within a PKI hierarchy.
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Cryptography
Browse Cryptography terms for cybersecurity professionals.
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CRL配布
The mechanism and locations for making Certificate Revocation Lists (CRLs) available to PKI participants to check the revocation status of certificates.
View termHSMアプライアンス
A dedicated hardware device designed to securely generate, manage, and store cryptographic keys, and perform cryptographic operations in compliance with security standards (e.g., FIPS 140-3).
View termMACアルゴリズム
A cryptographic function that produces a short piece of information used to authenticate a message and provide integrity, such as HMAC or CMAC.
View termOCSPステープリング
A TLS extension that allows servers to send a time-stamped OCSP response for their certificate during handshake, improving performance and privacy in revocation checking.
View termPIN入力
The act of securely entering a personal identification number (PIN) into a trusted hardware or software interface for authentication or key release.
View termPKIインフラストラクチャ
A system of hardware, software, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates in a public key environment.
View termエフェメラルキー
A cryptographic key generated for temporary use in a single session or operation, after which it is discarded and not reused, ensuring forward secrecy in protocols like TLS and ECDH.
View termオンラインステータス
In cryptography/PKI, refers to the real-time validity of a digital certificate or credential as determined by protocols such as OCSP.
View termオンラインレスポンダ
A network service that provides real-time certificate status information, typically using the Online Certificate Status Protocol (OCSP) to validate if a certificate is revoked or still valid.
View termキーのチェックサム
A value derived from a cryptographic key using a checksum or hash algorithm, used to verify the integrity or correctness of the key material.
View termキーのバックアップ
The secure process of creating a protected copy of a cryptographic key, enabling recovery if the original is lost or damaged, following strict policies and controls.
View termキーのローテーション
The scheduled process of replacing cryptographic keys with new keys to limit the period a compromised key can be misused and to enhance long-term security in cryptographic systems.
View termキーの有効期間
The maximum period that a cryptographic key is allowed to be active and used for cryptographic operations before mandatory expiration or replacement.
View termキーインポート
The process of securely bringing a cryptographic key into a software or hardware cryptographic module, typically in compliance with strict key handling and integrity procedures.
View termキーコンテナ
A logical or physical storage area used to hold cryptographic keys, often protected by access controls and used in software keystores or hardware security modules.
View termキーラッピング
The process of encrypting one cryptographic key with another key to securely transport or store keys, typically used for key distribution or archival.
View termキーリカバリ
A controlled process for restoring lost or inaccessible cryptographic keys, typically from a secure backup or escrow, for continuity and compliance.
View termキー使用法
A certificate extension that defines the allowed cryptographic operations for the associated key, such as digital signature or key encipherment.
View termサブCA
A Certificate Authority (CA) that is certified and authorized by a root or higher-level CA to issue digital certificates within a Public Key Infrastructure (PKI).
View termサブジェクト名
The distinguished name (DN) in a digital certificate that uniquely identifies the certificate holder or entity, as specified in X.509 standards.
View termサブジェクト鍵
The cryptographic public key associated with the subject of a digital certificate, used to verify signatures or encrypt messages to the certificate holder.
View termセキュアチャネル
A communication path protected by cryptographic means, ensuring confidentiality, integrity, and authentication of data in transit.
View termセッションチケット
A data structure issued by a server to a client in TLS to enable stateless session resumption by encapsulating keying material and session state, reducing handshake overhead.
View termセッション再開
A TLS or secure channel mechanism that enables clients and servers to reuse a previously negotiated session state for faster reconnection and reduced handshake overhead.
View termセッション鍵
A temporary symmetric key used for a single communication session, providing confidentiality and integrity for exchanged data and discarded after the session ends.
View termソルト値
A random value added to data, typically passwords, before hashing to ensure that identical inputs produce different hash outputs, preventing precomputed attack vectors such as rainbow tables.
View termタイムスタンプ付与
The process of recording the exact date and time that a digital document or transaction was created or signed, often with cryptographic proof provided by a Time Stamping Authority (TSA).
View termチェーンアンカリング
The process of ensuring that a certificate chain terminates at a trusted root certificate authority (trust anchor), as required in secure PKI implementations.
View termチェーンバリデーション
The process of verifying each certificate in a chain from the end entity up to the root CA, ensuring all links are trusted and unbroken in PKI trust models.
View termチェーン構築
The process of assembling a complete, ordered set of certificates from an end-entity certificate up to a trusted root, verifying each link in the trust chain.
View termデジタル封筒
A mechanism in cryptography where a message is encrypted with a symmetric key and the symmetric key is then encrypted with a recipient’s public key, ensuring confidentiality and key transport.
View termデバイス証明書
A digital certificate issued to a device (such as a server, router, or IoT component) to authenticate its identity within a secure network or PKI.
View termトラステッドプラットフォーム
A computing environment equipped with hardware and software components (e.g., TPM, secure boot) designed to ensure integrity, confidentiality, and authenticity of cryptographic operations and data.
View termトラストアンカー
A trusted entity (typically a root certificate authority) whose public key is used as the ultimate basis for validating the digital signatures and certificates in a PKI.
View termトラストストア
A repository of trusted root and intermediate certificates used by applications and systems to verify the authenticity of digital certificates.
View termトラストフレームワーク
A formal structure of policies, roles, rules, and standards that define how trust is established, maintained, and evaluated in a digital ecosystem, particularly in PKI, identity, and federation systems.
View termトークナイゼーションサービス
A security process or managed solution that replaces sensitive data elements with non-sensitive equivalents (tokens), often used to protect payment, personal, or healthcare information.
View termトークンバインディング
A security mechanism where cryptographic tokens are cryptographically bound to a TLS connection, ensuring that tokens cannot be replayed or used outside the original session.
View termトークンリクエスト
A formal operation in which a client requests an authentication or authorization token from an identity provider or security token service in PKI or OAuth2 contexts.
View termノンス値
A randomly or pseudo-randomly generated number used only once in a cryptographic communication to prevent replay attacks and ensure uniqueness.
View termノンス生成
The process of generating a unique, unpredictable, and usually random number (nonce) used once per cryptographic protocol operation to prevent replay attacks and ensure freshness.
View termハイブリッド暗号化
A cryptographic approach that combines asymmetric and symmetric encryption to leverage the advantages of both for secure key exchange and efficient data encryption.
View termハッシュ衝突
An event where two different inputs produce the same output hash value from a cryptographic hash function, undermining data integrity.
View termハードウェアトークン
A physical device, such as a USB or smart card, used to store cryptographic keys and perform authentication or signing operations, enhancing security by isolating credentials from general-purpose devices.
View termブロック暗号
A symmetric key encryption algorithm that encrypts data in fixed-size blocks, such as AES and 3DES.
View termポリシーマッピング
The process in PKI where certificate policies from one CA are mapped to equivalent policies in another, allowing interoperability and trust across different domains.
View termポリシー機関
An entity within a PKI or trust framework responsible for defining, governing, and maintaining security and operational policies for certificate authorities and relying parties.
View termメッセージダイジェスト
A fixed-length, unique output value generated by applying a cryptographic hash function to a message, used for verifying data integrity.
View termランダムオラクル
A theoretical black box model that responds to every unique query with a truly random response, used as an idealized component in proofs of cryptographic security.
View termルートストア
A trusted repository of root CA certificates used by operating systems and applications to validate the trustworthiness of digital certificates in PKI.
View termルート証明書
A self-signed digital certificate that identifies a trusted Certificate Authority (CA) at the apex of a certification chain, serving as a trust anchor for all subordinate certificates.
View termルート認証局
The top-level Certificate Authority (CA) in a PKI hierarchy whose root certificate is self-signed and serves as the ultimate trust anchor for all certificates issued in the infrastructure.
View term事前共有鍵
A symmetric key distributed to and shared by parties before communication begins, commonly used in VPNs, Wi-Fi WPA2-PSK, and certain secure channel protocols.
View term公開鍵
The openly distributed cryptographic key in an asymmetric key pair, used to verify digital signatures or encrypt data for the corresponding private key holder.
View term共通鍵
A cryptographic key used in symmetric encryption where the same key is used for both encryption and decryption operations.
View term前方秘匿性
A cryptographic property ensuring that the compromise of long-term keys does not compromise past session keys, providing strong protection for historic data in protocols like TLS.
View term失効状態
The current validity state of a digital certificate, indicating whether it has been revoked by the issuing certificate authority (CA) and is no longer trusted.
View term失効状態
The current validity state of a digital certificate as determined by a recognized Certificate Authority (CA), typically indicating whether a certificate is active, revoked, or suspended per OCSP, CRL, or similar mechanisms.
View term属性証明書
A digital certificate that binds attribute information (such as roles or permissions) to a subject, separate from the identity certificate, for use in access control.
View term暗号コンプライアンス
Adherence to laws, regulations, and standards that govern cryptographic practices, algorithm usage, and key management, ensuring security, privacy, and auditability.
View term暗号スイート
A named set of cryptographic algorithms used to negotiate security settings in network protocols like TLS, including key exchange, bulk encryption, and message authentication algorithms.
View term暗号フィードバック
A block cipher mode of operation (CFB) that turns a block cipher into a self-synchronizing stream cipher, providing confidentiality by encrypting feedback blocks.
View term暗号プロセッサ
A hardware device or chip specifically designed to perform cryptographic operations such as encryption, decryption, signing, and key management, often used to enhance security and performance.
View term暗号解析攻撃
A method of attacking cryptographic systems by analyzing the algorithms and ciphertexts to extract secret keys or plaintext without direct key compromise.
View term有効期間
The designated timeframe during which a cryptographic certificate or key is considered valid and trusted for use, after which it is expired or invalidated.
View term検証機関
A trusted service or entity that provides real-time or historical status information about digital certificates, typically via OCSP or CRL protocols.
View term楕円曲線
A type of algebraic curve used in public-key cryptography, providing strong security with smaller key sizes; the basis of Elliptic Curve Cryptography (ECC) standards.
View term発行ポリシー
A formal document or set of rules that defines the procedures and requirements for issuing digital certificates within a PKI.
View term発行者識別子
A unique value or distinguished name that identifies the Certificate Authority (CA) or entity that issues a digital certificate within a PKI, per X.509 and RFC 5280 standards.
View term発行者鍵
The private key held by a Certificate Authority (CA) or issuer used to sign digital certificates and assert trust in a PKI environment.
View term登録サービス
A trusted PKI component that manages requests for digital certificates, validates identity, and issues or renews certificates for users and devices.
View term監査ログ記録
The process of recording security-related events, operations, or accesses within a cryptographic or PKI environment to provide accountability, traceability, and forensics.
View term相互認証
A security process in which both entities in a communication verify each other's identities, typically using digital certificates or cryptographic mechanisms.
View term秘密鍵
A confidential cryptographic key in an asymmetric key pair, used to sign or decrypt data, and must be kept secret to maintain security.
View term署名アルゴリズム
A cryptographic algorithm used to generate and verify digital signatures, ensuring data authenticity and integrity, such as RSA, ECDSA, or EdDSA.
View term署名スキーム
A cryptographic algorithm for creating and verifying digital signatures, specifying mathematical processes and key structures, e.g., RSA-PSS, ECDSA.
View term署名パディング
A method of formatting a message or hash before digital signature creation, used to prevent certain attacks and ensure compatibility with cryptographic algorithms such as RSA-PSS or PKCS#1 v1.5.
View term署名ポリシー
A set of technical and procedural requirements governing the creation, validation, and management of digital signatures within a PKI or eIDAS framework.
View term署名付きアサーション
A digital statement or claim, such as an authentication response or attribute, that is cryptographically signed to ensure authenticity and integrity.
View term自己署名証明書
A digital certificate that is signed by the same entity whose identity it certifies, rather than by a trusted Certificate Authority (CA).
View term証明書チェーン
An ordered sequence of certificates, from an end-entity certificate up to the root authority, each certifying the next in the path, establishing a trust relationship.
View term証明書テンプレート
A predefined configuration for certificate attributes and extensions, used by CAs to automate and standardize certificate issuance in enterprise PKI environments.
View term証明書パス
An ordered sequence of certificates from the end-entity certificate to a trusted root certificate, used to establish trust in PKI validation processes.
View term証明書ピニング
A security technique that restricts which certificates are considered valid for a particular service or domain, by storing a hash of the expected certificate or public key in the client or application.
View term証明書ポリシー
A set of rules and practices that indicates the applicability of a certificate to a particular community or class of applications with common security requirements.
View term証明書ロールオーバー
The managed transition from an expiring or old certificate to a new certificate in a way that minimizes service interruption and maintains trust.
View term証明書更新
The process of issuing a new certificate for an entity before the expiration of the current certificate, maintaining continuity of trust without changing the subject's identity or keys.
View term量子耐性
The property of cryptographic algorithms to withstand attacks by quantum computers, typically achieved by using post-quantum cryptography schemes.
View term鍵の抽出
The process of obtaining a cryptographic key from a hardware or software source, typically for backup, migration, or forensic analysis, requiring strict security controls.
View term鍵エスクロー
A key management process in which cryptographic keys are held in escrow by a trusted third party, enabling recovery under defined conditions such as legal access.
View term鍵ペア
A set of two mathematically linked cryptographic keys, typically consisting of a public key for encryption/verification and a private key for decryption/signing.
View term鍵合意
A cryptographic protocol that enables two or more parties to establish a shared secret key over an insecure channel, commonly using protocols like Diffie-Hellman or ECDH.
View term鍵導出
A cryptographic process for generating one or more secret keys from a shared secret or password using a deterministic function, as specified in NIST SP 800-108/132.
View term鍵確認
A cryptographic process where parties confirm to each other that they possess the same secret key, usually as a final step in key agreement protocols.
View term鍵管理
The set of processes and mechanisms for generating, distributing, storing, using, rotating, archiving, and destroying cryptographic keys within a secure lifecycle, ensuring their confidentiality, integrity, and availability as specified by cryptography and PKI governance standards.
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