What Is Key Encoding?
This section describes private and public key encoding standards: PKCS#8 is used for encoding private keys and X.509 is used for encoding public keys.
What is Key Encoding?
Key encoding is the process of converting encryption and decryption keys, or private and public keys,
into a specific encoding format for storing them in files or transmitting them to remote systems.
As you can see from the previous chapter, JDK supports two commonly used key encoding standards:
- PKCS#8 - PKCS stands for Public-Key Cryptography Standards, developed by RSA Security currently
a division of EMC. PKCS#8 describes syntax for private-key information, including a private key
for some public-key algorithm and a set of attributes. PKCS#8 is mainly used to encode private keys.
- X.509 - X.509 is an ITU-T standard for a public key infrastructure (PKI) for single sign-on
and Privilege Management Infrastructure (PMI). X.509 specifies, amongst other things,
standard formats for public key certificates, certificate revocation lists, attribute certificates,
and a certification path validation algorithm.
To manage different key encoding standards, JDK offers a group of classes:
- KeyFactory - A class to convert keys between Key objects and EncodedKeySpec objects.
- EncodedKeySpec - An abstract class offers a grouping point of all sub classes that represent
various key encoding standards.
- PKCS8EncodedKeySpec - A sub class of EncodedKeySpec represents the ASN.1 encoding
of a private key based on PKCS#8 standard.
- X509EncodedKeySpec - A sub class of EncodedKeySpec represents the ASN.1 encoding
of a public key based on X.509 standard.
See next sections on how to use these key encoding classes.
Last update: 2014.
Table of Contents
About This JDK Tutorial Book
Downloading and Installing JDK 1.8.0 on Windows
Downloading and Installing JDK 1.7.0 on Windows
Downloading and Installing JDK 1.6.2 on Windows
Java Date-Time API
Date, Time and Calendar Classes
Date and Time Object and String Conversion
Number Object and Numeric String Conversion
Locales, Localization Methods and Resource Bundles
Calling and Importing Classes Defined in Unnamed Packages
HashSet, Vector, HashMap and Collection Classes
Character Set Encoding Classes and Methods
Character Set Encoding Maps
Encoding Conversion Programs for Encoded Text Files
Socket Network Communication
Datagram Network Communication
DOM (Document Object Model) - API for XML Files
SAX (Simple API for XML)
DTD (Document Type Definition) - XML Validation
XSD (XML Schema Definition) - XML Validation
XSL (Extensible Stylesheet Language)
Message Digest Algorithm Implementations in JDK
Private key and Public Key Pair Generation
►PKCS#8/X.509 Private/Public Encoding Standards
►What Is Key Encoding?
PKCS#8 and X.509 Key Encoding Classes
java.security.KeyFactory - Reading Encoded Keys
JcaKeyFactoryTest.java - Key Factory Test Program
Reading DSA Private and Public Key Files
Reading RSA Private and Public Key Files
Digital Signature Algorithm and Sample Program
"keytool" Commands and "keystore" Files
KeyStore and Certificate Classes
Secret Key Generation and Management
Cipher - Secret Key Encryption and Decryption
The SSL (Secure Socket Layer) Protocol
SSL Socket Communication Testing Programs
SSL Client Authentication
HTTPS (Hypertext Transfer Protocol Secure)
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