Abstract: An advanced metering infrastructure (AMI) server, an AMI network node, an AMI network system and a message broadcasting method thereof are provided. The AMI server generates a broadcasting key from a broadcasting message through a hash function, encrypts the broadcasting message into an encrypted broadcasting message via the broadcasting key, encrypts the broadcasting key into an encrypted key via a symmetric key, and transmits the encrypted broadcasting message and the encrypted key to the AMI network node. The AMI network node decrypts the encrypted key into the broadcasting key via the symmetric key, decrypts the encrypted broadcasting message into the broadcasting message via the broadcasting key, and processes the broadcasting message after determining that the broadcasting message corresponds to the broadcasting key through the hash function.

Abstract: An encryption method and decryption method are provided. The encryption method divides an electronic file into a plurality of message blocks, wherein the message blocks have a sequence. The encryption method sets a checking vector as the last message block. The encryption method performs the following steps on each message block according to the sequence: generating an input block, deriving an output block by encrypting the input block by an encryption key, and deriving an encrypted block by applying XOR operation to the output block and the previous message block, wherein the input block is equivalent to applying XOR operation to the message block, the output block corresponding to the previous message block, and the message block before the previous one. The encryption method generates an electronic encrypted file by concatenating the encrypted blocks. The decryption method performs a series of operations corresponding to the above operations.

Abstract: An encryption method and decryption method are provided. The encryption method divides an electronic file into a plurality of message blocks, wherein the message blocks have a sequence. The encryption method sets a checking vector as the last message block. The encryption method performs the following steps on each message block according to the sequence: generating an input block, deriving an output block by encrypting the input block by an encryption key, and deriving an encrypted block by applying XOR operation to the output block and the previous message block, wherein the input block is equivalent to applying XOR operation to the message block, the output block corresponding to the previous message block, and the message block before the previous one. The encryption method generates an electronic encrypted file by concatenating the encrypted blocks. The decryption method performs a series of operations corresponding to the above operations.

Abstract: An advanced metering infrastructure (AMI) server, an AMI network node, an AMI network system and a message broadcasting method thereof are provided. The AMI server generates a broadcasting key from a broadcasting message through a hash function, encrypts the broadcasting message into an encrypted broadcasting message via the broadcasting key, encrypts the broadcasting key into an encrypted key via a symmetric key, and transmits the encrypted broadcasting message and the encrypted key to the AMI network node. The AMI network node decrypts the encrypted key into the broadcasting key via the symmetric key, decrypts the encrypted broadcasting message into the broadcasting message via the broadcasting key, and processes the broadcasting message after determining that the broadcasting message corresponds to the broadcasting key through the hash function.