Abstract:Smart residential areas information portal system contains a large number of sensitive data related to the residential life and property security. In order to ensure the confidentiality of the data, optimized AES encryption algorithm is used to encrypt the data to reduce the encryption time, thereby reducing the communication time delay, which improves the performance of the system a lot. The principle, as well as the flow of encryption and decryption of AES algorithm, is analyzed in the following sections. In order to overcome the problem that the time used in decryption is longer than in encryption, a simplest matrix in the Galois field GF(2^8) is going to be adopted in MixColumn and inverse MixColumn operation to reduce the computation and time consumption in decryption. And then based on this, the steps in encryption and decryption process is merged and optimized in some degree, reducing the storage space, at the same time it can keep the execution efficiency. In the Visual Studio 2010 platform, several optimized AES algorithms are implemented in intelligentHome by adopting C language. It shows that the proposed optimized algorithm has higher efficiency and occupies less storage space.