Symmetric Key Encryption between JAVA and IOS

There has been a exponential increase in REST services implementation between IOS/Android devices and Java Middleware, This has become the solution architecture for most applications which provide support on IOS/Android devices and also provide interface on web using java web application.

To make the communication secure it is necessary that this REST messages are made secure. This can be achieved using symmetric encryption mechanism.

Hashing + Symmetric Key Encryption

This post explains the concept of Hashing and how to use the generated hash key to generate a symmetric key which can be used to encrypt and decrypt data.

This kind of security is generally used in banks.

Hashing is a one way process unlike encryption. A encrypted data can be decrypted using the key by which the data was encrypted, but a hashed data can not be converted into its original data using the key or mostly called as salt.

Symmetric and Asymmetric key Encryption with Key tool

This post explains the concept of combining symmetric key and asymmetric key encryption with the use of key tool. For example which does this without the keytool refer here

Symmetric + Asymmetric + Signature

This type of security is more strong and secure then asymmetric key encryption. We have already seen how we can combine symmetric and asymmetric key encryption here. In this post we add more security by adding the concept of Digital Signature. In Symmetric + Asymmetric key we encrypt the symmetric key with the public key of a asymmetric key to make the symmetric key an message more secure, but still the authenticity of the sender of the encrypted symmetric key is not verified. This can be achieved by using Digital signature. To understand Digital signature first refer this post .

Java Digital Singnature

Digital Signatures are used to authenticate the sender sending the message. Digital signature are also based on Asymmetric key Encryption mentioned here. Here the sender signs the message by its private key and any receiver can verify the signature who has the public key. An analogy for digital signatures is the sealing of an envelope with a personal wax seal. The message can be opened by anyone, but the presence of the unique seal authenticates the sender. This is termed in Java as Digital Signature.