The NIST Competition

DES Was Dying

By the mid-1990s, DES was in trouble.

Its 56-bit key could be brute-forced. The EFF proved this in 1998 by cracking DES in under a day.

Triple DES worked, but it was three times slower than single DES. Not ideal for a world moving online.


The cryptographic community needed something new. Something fast, secure, and built for modern hardware.

NIST decided to hold a public competition to find the next encryption standard.


The Competition

Unlike DES, which was designed behind closed doors by IBM and the NSA, this would be different.

Open. Transparent. Global.

Anyone could submit a cipher. Anyone could try to break the submissions.


1997: NIST announces the requirements

RequirementSpecification
Block size128 bits
Key sizes128, 192, and 256 bits
PerformanceFast in hardware and software
LicenseRoyalty-free worldwide

1998: Submissions close

15 candidates arrived from around the world.

Ciphers from the USA, Europe, Asia, and beyond. Each claiming to be the future of encryption.


1999: Five finalists

After a year of public analysis, NIST narrowed it down:

CipherOriginDesigners
RijndaelBelgiumRijmen, Daemen
SerpentUK/Israel/NorwayAnderson, Biham, Knudsen
TwofishUSASchneier et al.
RC6USARivest et al.
MARSUSAIBM

2000: Rijndael wins

After three years of attacks, analysis, and debate, NIST made the call.

Rijndael (pronounced “rain-doll”) became the Advanced Encryption Standard.


Why Rijndael?

The cipher was created by two Belgian cryptographers:

  • Vincent Rijmen
  • Joan Daemen

The name “Rijndael” combines their surnames.


It won because of balance.

Serpent was arguably more secure, but slower.

Twofish was fast, but more complex to implement.

Rijndael hit the sweet spot:

  • Fast on everything from 8-bit smart cards to 64-bit servers
  • Clean mathematical structure, easy to analyze
  • Simple enough to implement correctly

A New Era of Trust

The DES era had a shadow of doubt. Designed in secret, with NSA involvement. Did it have backdoors?

AES was different.

Three years of open cryptanalysis. Hundreds of researchers attacking all 15 candidates. Rijndael survived.


The timeline:

YearEvent
1997Competition announced
199815 candidates submitted
19995 finalists selected
2000Rijndael wins
2001Published as FIPS 197, officially named AES

AES has been the global standard for over two decades.

It encrypts your WiFi, your banking, your messages. No practical attack has ever broken it.

Next, we’ll look at how it works.