Aiming at the problem that most mapping algorithms based on virtual Software Defined Network （vSDN） do not fully consider the correlation between nodes and links， a vSDN mapping algorithm based on network topology segmentation and clustering analysis was proposed. Firstly， the complexity of physical network was reduced by the topology segmentation method based on the shortest hop count. Then， the request acceptance rate of mapping algorithm was improved by the clustering analysis method based on node topology and resource attributes. Finally， the nodes that do not meet the link requirements were remapped， by dispersing the link constraints to the bandwidth resources of nodes and the degrees of nodes to perform the consideration with constraints， so that the mapping process between nodes and links was optimized. Experimental results show that， the proposed algorithm can effectively improves the request acceptance rate of virtual network mapping algorithm based on Software Defined Network （SDN） architecture in physical networks with low connectivity probability.

MP3 as the de facto standard for digital music, the number of files is quite large and user access requirements rapidly grow up. How to effectively store and manage vast amounts of MP3 files to provide good user experience has become a matter of bigger concern. The emergence of Hadoop provides us with new ideas. However, because Hadoop itself is not suitable for handling massive small files, this paper presented a Hadoop-based storage architecture for massive MP3 files, fullly using the MP3 file’s rich metadata. The classification algorithm by pre-processing module would merged small files into sequence file, and the introduction of efficient indexing mechanism served as a good solution to the problem of small files. The experimental results show that the approach can achieve a better performance.

To make the statistical measures derived from Gray Level Co-occurrence Matrix (GLCM) provide better information about the texture, sufficient experiments were done on the Brodatz pictures. Firstly, by testing the effect of each parameter on the key statistics，the changing rule of the statistics along with different parameters was obtained and proper parameters were advised. Then the stability of these statistics was analyzed when the image was rotated or its size was changed. The experimental and analytical results provide valuable reference for creating GLCM better and achieving image retrieval based on texture information.