The air was cool when we walked through the Kotabaru area. The shady trees stood tall in the middle of the road, protecting us from the scorching heat of the sun. Several Indis-style buildings can be seen here and there, evoking memories of the colonial past. In one of these buildings, there was a large sign that read “The Password Museum” which caught our attention. This is our real goal: the Password Museum, the only cryptography museum in Indonesia. Apart from Indonesia, we can also find cryptography museums in the United States and the Netherlands (virtually).
Entering the museum lobby, we were immediately greeted by a friendly receptionist. For a moment, we were confused about finding ticket prices that are commonly found at the entrance. The receptionist only handed over a guest book, without any information about the tickets we had to buy. Investigate a calibaration, it turns out that we are not charged a penny to enter this museum. Even more fun, we can also be accompanied by a guide who is always ready to explain various interesting things that are rarely known by others.
The Sandi Museum was founded on the initiative of the Head of the National Sandi Institute and Sri Sultan Hamengku Bawono X in 2006. The construction of this museum was hampered by the earthquake in May 2006, before it was finally inaugurated in 2008. Initially, this museum shared the same building as the Museum of Struggle in Mergangsang area. In 2014, the museum moved to its current location in Kotabaru, occupying an old, disused Air Force building. This building has 2 floors with 9 display rooms that store various historical objects since the war of independence.
“Let’s go straight to the first room,” said Haris, our guide who always smiled while explaining various unique stories at the Sandi Museum.
We also entered the display room on the 1st floor which tells a lot about the life of dr. Roebiono Kertopati, the Father of State Encryption of the Republic of Indonesia.
Some rooms display various historical objects in the world of Indonesian coding, such as code books, couriers’ bicycles, and others. There are also several dioramas depicting the activities of the cipher officers during the war of independence. Excitedly, Haris explained various interesting stories about these objects.
“This diorama shows the atmosphere of the appointment of Dr. Roebiono as head of the Code Service in 1946,” said Haris, pointing to two statues sitting next to each other. “Under the leadership of Dr. Roebiono, the Code Service played an important role in Dutch Military Aggression 1 and 2, before finally changing its name to the National Crypto Agency.”
According to Haris, at the beginning of independence, various institutions in Indonesia were still using the old code from the colonial period, making it easy for the Dutch army to hack. Realizing this, dr. Roebiono also took the initiative to form a new code that can only be used by the Republic of Indonesia. These new passwords are written in 6 books called the “C Code Book”, each containing 10,000 passwords in Dutch and English.
In order for this new code system to be recognized for its existence, dr. Roebiono hacked various other passwords used by various state agencies. This action made these agencies aware of how weak the old password they were using was, so they agreed to use the new password created by dr. Roebiono.
During the 2nd Dutch Military Aggression in 1948, the Republic of Indonesia almost disappeared from history. The Dutch military managed to capture several leaders of the Republic of Indonesia, including Ir Soekarno and Moehammad Hatta. At this time, Dr. Roebiono and several Code Officers (CDO) of his subordinates took the initiative to burn all confidential documents at the Code Service before they fell into the hands of the Dutch.
They also spread to various regions in Indonesia, ensuring the security of communications between the emergency government. Sjarifoeddin Prawiranegara with various guerrilla troops in Indonesia. One of the well-known encoding centers is in Dukuh Hamlet, Purwoharjo Village, Samigaluh, Kulonprogo.
“At this time, the cipher officers work in rudimentary conditions,” said Haris, pointing to a diorama of a joglo house in one of the rooms. “They work only using handwriting, accompanied by a spray lamp at night.”
With enthusiasm, Haris told the various tricks used by the couriers to deliver secret messages without the Dutch troops knowing. For example, there are several couriers who modify the handlebars of onthel bicycles so that messages can be infiltrated. There are also those who put a message in the snack, so that it can be swallowed when there is a Dutch army raid.
Satisfied with hearing the heroic stories from the war for independence, we moved to another room. Here, we can see various old cipher machines used by several countries in the world, from the United States, the Vatican, Germany, and others. There are also several cipher machines made by Indonesian children. Unfortunately, there is no information on how the machines work, so we have to be content with just seeing the shape from behind the glass.
Apart from seeing modern cipher machines and tools, visitors to the Password Museum can also learn how simple ciphers work from the past. For example, Skytale, a scroll-shaped code used in Ancient Greece. There is another Cardan Grille, a long written password that can be cracked using a special key in the shape of a perforated paper.
Then there is the Book Cipher, a long written cipher similar to Cardan Grille but with a key in the form of a sequence of numbers, each indicating the position of a letter in a paragraph. For example the number 23412, the first number indicates the paragraph, the second number indicates the order of sentences and so on.
One of the most unique ciphers is the tattoo cipher, dating to 499 BC and used by the Greek tyrant Histiaeus. The tyrant used a slave as a messenger, which was sent by a certain method so as not to be noticed by the enemy. The message was addressed to his son-in-law, Aristagoras, in a war in Persia.
“The password was written as a tattoo on the shaved head of the slave. Histiaeus waited until the slave’s hair grew back and covered the tattoo, then sent it to his son-in-law, Aristagoras,” said Haris, pulling a wig from a mannequin. “When it arrives, the slave is sheared again so that the message can be read.”
In the last room, there are several computers that we can use to find out more complete information about the science of cryptography. Apart from that, there are also several cipher games that challenge us to crack the vigenere cipher, a classic cipher system that forms the basis of modern ciphers in many countries. Through this facility, we can also get to know the world of cryptography in Indonesia more closely.