Experts state that cryptography is an encryption system that transforms information shared between two people or parties into a form that cannot be understood by unwanted individuals, and that cryptography is utilized today when messaging with mobile phone applications, signing electronic documents, shopping from websites, and in internet banking applications. Emphasizing that cyber attacks have increased after the pandemic, Dr. Assistant Professor Fatih Temiz recommends avoiding easily guessable information such as birth dates, founding dates of favorite teams, and license plate numbers when choosing passwords for security, and underlines the importance of ensuring that the website or mobile application is original when entering our password.
Is the mobile app and website you are transacting on original?
Dr. Assistant Professor Fatih Temiz from Üsküdar Üniversitesi Faculty of Engineering and Natural Sciences, Department of Computer Engineering, shared information and advice about cryptography, the encryption system still used today.
It has a history as old as the invention of writing
Dr. Assistant Professor Fatih Temiz stated that cryptography is the science of encryption that aims for secure communication between two people or parties and enables information to be transformed into a form that cannot be understood by unwanted individuals. He said, "It comes from the combination of the Old Greek words kryptos (hidden) and grapheia (writing). We can say that the history of cryptography is almost as old as the invention of writing. Some scientists even believe that the invention of writing itself was a type of cryptography, or secret communication."
Also used by Julius Caesar
Dr. Assistant Professor Fatih Temiz stated that one of the oldest known examples of cryptography was used by the Roman Emperor Julius Caesar in BCE, and continued:
"Julius Caesar communicated with his soldiers using the Caesar cipher, named after him today. In this cipher, each letter was replaced by the third letter after it in the alphabet, creating a meaningless message. For example, the message 'Üsküdar' was transformed into the meaningless text 'ZUNZGÇT' for those unaware of the method. Those who knew the cipher would obtain the plain message 'Üsküdar' again by changing the letters of the 'Zunzgçt' ciphertext with the third letters before them. A similar and simple encryption method is one where letters are replaced by any other letter in the alphabet. Although in this encryption method there are an incredibly large number of different possible situations to break the cipher, for example, 8, 841, 761, 993, 739, 701, 954, 543, 616, 000, 000 in Turkish, these cryptosystems can be solved in seconds using letter frequency statistics of languages."
Germans invented Enigma in the 20th century
Dr. Assistant Professor Fatih Temiz stated that these and similar encryption methods, which are now primitive, were replaced by electromechanical devices such as the famous Enigma encryption machine in the 20th century. He said, "Enigma, invented by the Germans, played a crucial role in the course of World War II. Enigma, which could transform the same letter into different letters or different letters into the same letter depending on its position, was thought to be perfect and unbreakable. There were approximately 160 quintillion different possible settings for Enigma, and these settings were changed daily. Meanwhile, a team at Bletchley Park in England, including Alan Turing, known today as the father of computer science and artificial intelligence, was working to break Enigma. They eventually succeeded in breaking Enigma's code by developing a device called Bombe, which is considered one of the first known computers. Historians believe that this event led to the war ending two years earlier and saved millions of lives."
Cryptography is still used today
Dr. Assistant Professor Fatih Temiz stated that cryptography, which was primarily used in military and diplomatic fields historically, began to be used in a very wide range with the development of modern computer technology and the widespread use of the internet. He said, "Today, we use cryptography when messaging with mobile phone applications, shopping from websites, using internet banking, blockchain technology, and smart home systems. We also use cryptography when signing a document with an electronic signature or performing electronic identity verification."
Used for secure communication
Emphasizing that cryptography is primarily used for secure communication and messaging, Dr. Assistant Professor Fatih Temiz said, "In today's information age, we constantly transmit a large volume of data. Cryptography is used to ensure our security during these communications. Cryptography is utilized in products we use to ensure our personal privacy, home and vehicle security, and financial security. We also use cryptography for identity verification and document signing purposes. For example, passwords we set for email or social media accounts are not stored in databases in their exact form. They are transformed and stored as complex and seemingly meaningless expressions using special functions called cryptographic hash functions."
Cyber attacks increased after the pandemic
Dr. Assistant Professor Fatih Temiz noted that in recent years, especially after the Covid-19 pandemic, cyber attacks have accelerated and proliferated tremendously as many companies began working remotely. He stated, "While most attacks on such companies or institutions target security vulnerabilities, social engineering and phishing attacks are mostly carried out against individuals. A commonly used method is to try to obtain passwords by redirecting individuals to fake replicas of well-known websites. Passwords for social media and email accounts are frequently attempted to be stolen and changed using this method."
Attention should be paid to password selection
Dr. Assistant Professor Fatih Temiz emphasized that when choosing our passwords, we should be careful not to include information that is known or guessable by others, and continued:
"Information such as our birth date, favorite team, or license plate number is quite risky for password selection. For example, there are programs that quickly try many commonly used or meaningful passwords for many people for Wi-Fi passwords. The length of passwords is also an important criterion for security. Short passwords are much easier to crack. That's why many websites impose requirements such as password length, uppercase letters, lowercase letters, and special characters. One of the most secure password selections includes passwords that are meaningful only to the individual, contain 8 or more characters, and are of sufficient length, consisting of both uppercase and lowercase letters, as well as numbers or special characters."
It is necessary to ensure that sites are original
Dr. Assistant Professor Fatih Temiz stated that when entering our password into a website or mobile application, we must ensure that the site is original. He said, "We must avoid clicking on links in messages and emails that do not come from a reliable sender, or be very careful if we do. Furthermore, it should be remembered that public Wi-Fi networks are inherently insecure. When using such networks, a VPN should be used, or if not possible, no transactions involving credentials or credit cards should be made."