P2P directory search: Signature Array Hash Table

Bloom filters are a well known data structure for approximate set membership. Bloom filters are space efficient but require many independent hashes and consecutive memory accesses for an element test. In this paper, we develop a hash table data structure that stores string signatures in an array. This new signature array hash table (SAHT) supports faster element testing than a bloom filter and requires less memory than a standard hash table that uses linked-list chains. The SAHT also supports removal of elements (which a Bloom filter does not) and addition of elements at the expense of requiring about 1.5x more memory than a bloom filter with same false positive rate.