Symmetric ciphers

Symmetric ciphers use the same secret key to encrypt and decrypt, and their security is based on confidentiality of this key. We can divide symmetric ciphers into block symmetric ciphers and stream symmetric ciphers.

This is an archive article published 03/19/2018. Some information may no longer be up to date and in line with the current state. Please contact us in case of interest.

There are many types of symmetric ciphers, the most known are DES, or 3 DES and AES.

Encryption Standard DES
Data Encryption Standard was developed from an IBM-based algorithm that was named LUCIFER. This algorithm was designed within a project carried out by the research group and led by Horst Feistel. LUCIFER is a Feistel block cipher that works with 64-bit data blocks and the key has a length of 128 bits.

Encryption standard DES that was developed from this algorithm uses 64-bit data blocks and key with the length of 56 bits.
This standard was adopted in 1977 by the National Bureau of Standards, later by NIST (National Institute of Standard and Technology). The encryption algorithm was named as DEA (DataEncryptionAlgorithm).

Initially, the DES encryption standard was designed for applications in finance. In 1999, NIST adopted a new version of the DES standard called 3DES. It uses triple encryption using the DES algorithm and uses two or three different keys.

The potential vulnerability of the DES algorithm to the total test method has prompted an interest to find the alternative approaches and improve the original algorithm. One of the possibilities of enhancing the security of the DES algorithm is multiple encryption with multiple keys, which is the basis of DES algorithm modifications. The most used modifications of the DES algorithm are:

  • double DES
  • triple DES with two keys
  • triple DES with three keys

From our experience in electronic field we know that the use of 3DES encryption mechanisms is also used in RFID products, for example ISO cards from ACM and readers from Stronglink

Encryption Standard AES

Since the long-term use of the DES encryption algorithm has shown the potential for its breakage, NIST announced a public tender in 1997 to select a new symmetric encryption algorithm to encrypt the data that was named AES (Advanced Encryption Standard). The aim was to choose an algorithm whose security would be greater than 3DES security, and would allow encrypting blocks of 128 bit length, or to work with 128, 192 and 256-bit keys.

In the first round, 15 cryptographic algorithms were selected and 5 algorithms (MARS, RC6, Rijndael, Serpent, Twofish) were short-listed. The resulting NIST rating was published in the form of a standard (FIPS PUB 197) in November 2001, with AES being based on the Rijndael algorithm, which was signed by the Belgian Joan Daemen and Vincent Rijmen.

The requirements for the new AES standard formulated by NIST were divided into 3 categories:

  • security
  • costs
  • implementation

Security represents the amount of effort, or work needed to break the algorithm by cryptanalysis. Since 128 bits was determined as the minimum length of the AES key, the total test method using the current or the envisaged technologies was not taken into consideration.
AES costs were based on the assumption that this algorithm should cover a wide range of applications and should be of high computational efficiency in order to be applicable to applications with high transfer rates, for example in broadband networks.
Implementation covers a wide range of parameters such as, for example, flexibility, simplicity, and the ability to be used in a variety of hardware and software resources.

The AES encryption standard is also used by our long-term partner, Lantronix, in their Xport and xPico products

Symmetric ciphers form a broad category of algorithms that include both, block and stream ciphers. Their advantage is mainly the speed and disadvantage is the large number of encryption users, or the keys users, or their safe distribution. This was a challenge especially for cryptologists and the formation of cryptography with public key.

Our company, as one of many on the market, does not require special encryption systems. We keep saying, "The cost of data security must be less than the cost of encryption." Encryption mechanisms are expensive.
But, in the case of development companies where know-how protection is needed, you need to consider introducing encryption systems. However, it should be remembered that such encryption within the product may also lead to discomfort to the end-user, for example if they need to use an external encryption system. One of the best known is, for example, internet banking where authentication / authorization (SMS message, token, etc.) is required when entering a bank account. Or when buying a product - a hardware key is required for the software.

Do not miss these articles

Do you like our articles? Do not miss any of them! You do not have to worry about anything, we will arrange delivery to you.

Additional products

DESFIREEV14KISO ACM
RFID MIFARE® DESFire® EV1 4kb ISO Card 13,56MHz
Ord.number
124308
Manufacturer
ACM
in stock 856 pcs
1 pcs+ 1,39 €
ORDER:
  • ADD TO CART
  • Get Quote
  • Add to favorites
  • Add to watchdog
  • Add item to compare
SL032 STRONGLINK
RFID Reader/Writer 13,56MHz MIFARE® DESFfire®/NFC UART
Ord.number
124100
Manufacturer
in stock 230 pcs
(We are checking the delivery date: 100 pcs)
1 pcs+ 28,30 € 2 pcs+ 26,90 € 12 pcs+ 24,80 €
ORDER:
  • ADD TO CART
  • Get Quote
  • Add to favorites
  • Add to watchdog
  • Add item to compare
XP1002000-05R LANTRONIX
XPort SE w/AES 256bit Encryption
Ord.number
134246
Manufacturer
in stock 134 pcs
Currently in stock 139 pcs
Reserved for customers 5 pcs
Currently available 134 pcs
If you are interested in bigger quantity that is currently available in stock, please contact our sales assistant or click on Get Quote.
1 pcs+ 57,88 € 50 pcs+ 53,40 € 100 pcs+ 50,41 € 250 pcs+ 48,17 €
ORDER:
  • ADD TO CART
  • Get Quote
  • Add to favorites
  • Add to watchdog
  • Add item to compare
XPC100100B-01 LANTRONIX
xPico Device Server Extended Temp. & AES Encryption, Bulk
Ord.number
121785
Manufacturer
in stock 269 pcs
Currently in stock 619 pcs
Reserved for customers 350 pcs
Currently available 269 pcs
If you are interested in bigger quantity that is currently available in stock, please contact our sales assistant or click on Get Quote.
1 pcs+ 28,54 € 50 pcs+ 26,33 € 100 pcs+ 24,86 € 250 pcs+ 23,76 €
ORDER:
  • ADD TO CART
  • Get Quote
  • Add to favorites
  • Add to watchdog
  • Add item to compare
Do you agree with cookies being stored?
Welcome to the SOS electronic website. Before you enter our online world, we would like to ask you to allow us to store cookies on your browser. Your consent will help us view the site without error, measure its performance, and track additional statistics. Apart from that, we can bring you an offer of our products and services, literally tailor-made. We also provide cookies to third parties. However, you are definitely safe with us.
The proper operation of the website
More stable technical control
Better marketing offer

More about cookies
More about personal data processing