Nowadays, the construction and application of digital library leads a new era of the way people obtain knowledge and information, and promotes the academic exchanges and social progress. Digital library, however, also involves great risk, hacker attacks become the main…

Network Coordinate System embeds all nodes into a specific metric space and estimate the latency between any node-pair through computing the corresponding metric distance with low-cost. But the metric space is usually uniform while the Internet is heterogeneous since different…