A hash table randomly populated with byte patterns is used in finding the byte patterns in a sequence of bytes. A hash function is applied to information associated with a substring of the sequence of bytes to generate a key value. The key value is compared to the keys of the hash table, and if a match is found, the information associated with the substring is compared to corresponding information associated with a substring of a byte pattern stored in the hash table. If a match is found, the substring of the sequence of bytes is compared to the substring of the byte pattern. If a match is found, the substring is compared to the byte pattern.