Abstract: DHT network is the most widely used P2P protocol in the world and routing table is the key component for its self-organization.It’s difficult to measure the global routing table of a DHT network due to its feature of totally distributed architecture.In this paper,we propose a hybrid method to capture the snapshot of the routing table of DHT network.We first introduce a repetition degree to define the efficiency when crawling the snapshot.Then,we propose a DHT snapshot method that uses breadth-first search first and then changes to depth-first search.Finnally,we propose a self-adaptive method to crawl the routing tables based on the un-even feature of routing table.The experiment on Kad network shows that,the DHT snapshot method is 91.2% better than Blizzard,64.5% better than breadth-first and 27.4% better than depth-first.Routing table snapshot method reaches the best when g=5 and it is 187.4% better than the random method and 38.9% better than g＝7.

Key words: DHT,Routing table,Two layer model,Hybrid strategy,Self-adaptive strategy