This OS fingerprinting probe examines the remote server's implementation of TCP timestamps. Not all operating systems implement timestamps within the TCP header, but when timestamps are used then this provides the attacker with a means to guess the operating system of the target. The attacker begins by probing any active TCP service in order to get response which contains a TCP timestamp. Different Operating systems update the timestamp value using different intervals. This type of analysis is most accurate when multiple timestamp responses are received and then analyzed. TCP timestamps can be found in the TCP Options field of the TCP header. 1. The attacker sends a probe packet to the remote host to identify if timestamps are present.2. If the remote host is using timestamp, the attacker sends several requests and records the timestamp values.3. The attacker analyzes the timestamp values and determines an average increments per second in the timestamps for the target.3. The attacker compares this result to a database of known TCP timestamp increments for a possible match.