Key name. This follows the same syntax rules as other expression entity names: It must begin with an alpha character (A-Z or a-z) or an underscore (_). The rest of the characters must be alpha, numeric (0-9) or underscores. It cannot be re or xp (reserved for regular and XPath expressions). It cannot be an expression reserved word (e.g. SYS or HTTP). It cannot be used for an existing expression object (HTTP callout, patset, dataset, stringmap, or named expression).
This is mandatory parameter.

Cipher method to be used to encrypt and decrypt content. NONE - no encryption or decryption is performed The output of ENCRYPT() and DECRYPT() is the same as the input. RC4 - the RC4 stream cipher with a 128 bit (16 byte) key; RC4 is now considered insecure and should only be used if required by existing applciations. DES[-] - the Data Encryption Standard (DES) block cipher with a 64-bit (8 byte) key, with 56 data bits and 8 parity bits. DES is considered less secure than DES3 or AES so it should only be used if required by an existing applicastion. The optional mode is described below; DES without a mode is equivalent to DES-CBC. DES3[-] - the Triple Data Encryption Standard (DES) block cipher with a 192-bit (24 byte) key. The optional mode is described below; DES3 without a mode is equivalent to DES3-CBC. AES[-] - the Advanced Encryption Standard block cipher, available with 128 bit (16 byte), 192 bit (24 byte), and 256 bit (32 byte) keys. The optional mode is described below; AES without a mode is equivalent to AES-CBC. For a block cipher, the specifies how multiple blocks of plaintext are encrypted and how the Initialization Vector (IV) is used. Choices are CBC (Cipher Block Chaining) - Each block of plaintext is XORed with the previous ciphertext block, or IV for the first block, before being encrypted. Padding is required if the plaintext is not a multiple of the cipher block size. CFB (Cipher Feedback) - The previous ciphertext block, or the IV for the first block, is encrypted and the output is XORed with the current plaintext block to create the current ciphertext block. The 128-bit version of CFB is provided. Padding is not required. OFB (Output Feedback) - A keystream is generated by applying the cipher successfully to the IV and XORing the keystream blocks with the plaintext. Padding is not required. ECB (Electronic Codebook) - Each block of plaintext is independently encrypted. An IV is not used. Padding is required. This mode is considered less secure than the other modes because the same plaintext always produces the same encrypted text and should only be used if required by an existing application.
Possible Values : NONE, RC4, DES3, AES128, AES192, AES256, DES, DES-CBC, DES-CFB, DES-OFB, DES-ECB, DES3-CBC, DES3-CFB, DES3-OFB, DES3-ECB, AES128-CBC, AES128-CFB, AES128-OFB, AES128-ECB, AES192-CBC, AES192-CFB, AES192-OFB, AES192-ECB, AES256-CBC, AES256-CFB, AES256-OFB, AES256-ECB.