1. A method for traversing a compressed deterministic finite automata-based graph comprising: in a processor: traversing nodes in the compressed graph, the nodes being interconnected through valid arcs, by traveling node to node through a valid arc, where a current valid arc of a current node leads to a next node with a walker process to search for an expression in an input stream, the compressed graph having no redundant arcs, and each valid arc of the compressed graph representing a character match in the expression; and using a hash value generated from an input character to index in the current node and to read the current valid arc associated with the input character; using a hash function associated with the current valid arc to generate a hash value from a next input character; and indexing in the next node using the hash value generated from the next input character to read a next valid arc to manage the walker process.