In the previous tutorial, boolean arithmetic was introduced. It was shown that how binary numbers can be added, subtracted, multiplied and divided. In this tutorial, now logic operations on binary numbers will be discussed. The logic operations are not only the way to implement arithmetic operations (by means of combinational circuits), they form the building blocks of the digital circuits. A digital circuit is built by logic gates where the logic gates perform one or the other boolean logic operation.

The electronics too have no different way to represent, maintain and analyze information. Any information can be either discrete like names of things, events and properties or can be continuous which then require measurement by comparison to a standard unit, quantification and representation in numbers. The very foundation of science i.e. organized knowledge about understanding of nature and natural phenomena, is based on language and mathematics. Any branch of science involves identification of entities, their attributes, associated events and mathematical analysis of those attributes and events.

In the previous tutorial, it was seen how FTP protocol can be used to update application software on an IoT device. However, FTP protocol has some security concerns as it is vulnerable to several kind of attacks like Brute force attack, FTP bounce attack, Packet capture, Port stealing (guessing the next open port and usurping a legitimate connection), Spoofing attack, Username enumeration etc. Therefore, secure variants of FTP protocols were developed. SSH File Transfer Protocol is one of the secure variants of the FTP protocol.