Systems, methods, and other embodiments associated with data stream classification are described. One example method includes identifying packets associated with the data stream. The example method may also include updating a set of characterization data associated with the data stream based on information associated with a packet. The example method may also include assigning a data stream classifier to the data stream by comparing characterization data to identification data upon determining that the set of characterization data indicates that the data stream is able to be classified. The example method may also include providing a signal associated with the data stream classifier.