中文摘要：

详细阐述了用于测量Gnutella网络拓扑的爬行器的设计和实现，并实验性地测定了完成该网络拓扑快照的最佳快门延迟。

英文摘要：

The paper designs and implements a new crawler to extract the topology of the Gnutella network, and empirically deduces the shutter speed for an accurate topological snapshot.