PLWAH+: A bitmap index compressing scheme based on PLWAH

Archiving of the Internet traffic is essential for analyzing network events in the field of network security and network forensics. The bitmap index is widely used to achieve fast searching in archival traffic data requiring a large storage space. As current state-of-art, WAH, PLWAH and COMPAX are proposed for compressing bitmap indexes. In this paper, a new bitmap index compression scheme, named PLWAH+ (Position List Word Aligned Hybrid Plus), is introduced, based on PLWAH. With less storage consumption, PLWAH+ is more suitable for indexing in large-scale and high-speed network traffic.