Methods and systems are described for compressing a tree structure associating network packet signatures with network packet metadata, the tree structure comprising a plurality of non-leaf nodes of single bit test nodes and a plurality of leaf nodes comprising network packet metadata, the method comprising determining whether the sub-portion of the tree structure is to be compressed. If determination is made that the sub-portion of the tree structure is to be compressed, generating a compressed node data structure, the compressed node data structure comprising a path of the sub-portion of the tree structure, the path comprising a sequence of bits formed by a concatenation of the single bits associated with each one of the consecutive non-leaf nodes of the sub-portion of the tree structure, the number of bits of the sequence being equal or greater than the compression threshold.