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So What Is PKCS#7?

A symmetric key block cipher, such as AES and DES, uses a defined block size -and which stores a given number of bytes. These blocks are typically either 64-bits (8 bytes) or 128 bits (16 bytes). As we cannot fill all of the blocks, we must pad the last block. PKCS #7 (Cryptographic Message Syntax) is a standard padding method that determines the number of padding bytes and then ads that as a value. For example, for a 128-bit block size, and if we have…