DHTnil: An Approach to Publish and Lookup Nilsimsa Digests in DHT

Nilsimsa algorithm plays an important role in the digest-based anti-spam technique. Based on the research about Nilsimsa digest, we propose an approach to publish and lookup for Nilsimsa digests inDHT: DHTnil. In this paper, we discuss DHTnil's publication and lookup algorithm in detail, and evaluate the effectiveness of DHTnil through simulation experiments. For random generated digests, DHTnil can guarantee that the publication of a group of similar Nilsimsa digests involves no more than 3% of all subspaces, and the similar lookup of a digest involves no more than 3.5% of all subspaces to guarantee a recall rate of 80%. For real junk email samples collected from Internet, DHTnil has an even better performance.