128 bit block cipher camellia n.
Download
Skip this Video
Download Presentation
128-bit Block Cipher Camellia

Loading in 2 Seconds...

play fullscreen
1 / 18

128-bit Block Cipher Camellia - PowerPoint PPT Presentation


  • 192 Views
  • Uploaded on

128-bit Block Cipher Camellia. Kazumaro Aoki * Tetsuya Ichikawa † Masayuki Kanda * Mitsuru Matsui † Shiho Moriai * Junko Nakajima † Toshio Tokita † * NTT † Mitsubishi Electric Corporation. Outline. What’s Camellia?

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about '128-bit Block Cipher Camellia' - dalton-whitehead


Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
128 bit block cipher camellia

128-bit Block CipherCamellia

Kazumaro Aoki* Tetsuya Ichikawa†

Masayuki Kanda* Mitsuru Matsui†

Shiho Moriai* Junko Nakajima†

Toshio Tokita†

* NTT

† Mitsubishi Electric Corporation

outline
Outline
  • What’s Camellia?
  • Advantages over Rijndael
  • Performance Figures
  • Structure of Camellia
  • Security Consideration
  • Conclusion
what s camellia
What’s Camellia?
  • Jointly developed by NTT and Mitsubishi Electric Corporation
    • Designed by experts of research and development in cryptography
    • Inherited good characteristics from E2 and MISTY
  • Same interface as AES
    • block size: 128 bits
    • key sizes: 128, 192, 256 bits
faq why camellia
FAQ: Why “Camellia”?
  • Camellia is well known as “Camellia Japonica” botanically, and Japan is its origin.
  • Easy to pronounce :-)
    • unlike ….
  • Flower language: Good fortune, Perfect loveliness.
users demands on block ciphers
Users’ Demands on Block Ciphers

Reliability

Good Performer

Interoperability

AES coming soon!

Royalty-Free

(No IPR Problem)

No More

Ciphers!

advantage over rijndael
Advantage over Rijndael
  • Efficiency in H/W Implementations
    • Smaller Hardware 9.66Kgates (0.35mm rule)
    • Better Throughput/Area 21.9Mbit/(s*Kgates)
    • Much more efficient in implementing both encryption and decryption
  • Excellent Key Agility
    • Shorter key setup time
    • On-the-fly subkey computation for both encryption and decryption
advantage over rijndael cont
Advantage over Rijndael (Cont.)
  • Symmetric Encryption and Decryption (Feistel cipher)
    • Very little additional area to implement both encryption and decryption in H/W
    • Little additional ROM is favorable in restricted-space environments
  • Better performance in JAVA
  • Comparable speed on 8-bit CPUs
    • e.g. Z80
software performance 128 bit keys

229

238

258

308

312

759

Software Performance (128-bit keys)
  • Pentium III (1.13GHz)
    • 308 cycles/block (Assembly)

= 471Mbit/s

  • Comparable speed to the AES finalists

RC6

Encryption speed on P6 [cycles/block]

Rijndael

Twofish

Fast

Camellia

Mars

Serpent

*Programmed by Aoki, Lipmaa, Twofish team, and Osvik.

Each figure is the fastest as far as we know.

java performance 128 bit keys

Rijndael

19.32

Mars

19.72

Serpent

11.46

Twofish

19.27

JAVA Performance (128-bit keys)
  • Pentium II (300MHz)
    • 36.112Mbit/s (Java 1.2)
  • Above average among AES finalists

Speed*

[Mbit/s]

* AES finalists’ data by Sterbenz[AES3]

(Pentium Pro 200MHz)

Camellia’s datum is converted into 200 MHz

Camellia

24.07

RC6

26.21

hardware 128 bit keys

Area

[Kgates]

MARS

2,936

226

0.08

Rijndael

RC6

1,643

613

1,950

204

0.12

3.18

Serpent

504

932

1.85

Twofish

432

394

0.91

Hardware (128-bit keys)
  • ASIC (0.35mm CMOS)
    • Type II: Top priority: Size
      • Less than10KGates (212Mbit/s)
      • Among smallest 128-bit block ciphers
    • Type I: Top priority: Speed

Throughput

Thru/Area

[Mbit/s]

Camellia

273

1,171

4.29

The above data (except Camellia) by Ichikawa et al. are refered in NIST’s AES report.

structure of camellia
Structure of Camellia
  • Encryption/Decryption Procedure
    • Feistel structure

18 rounds (for 128-bit keys)

24 rounds (for 192/256-bit keys)

      • Round function: SPN
      • FL/FL-1-functions inserted every 6 rounds
      • Input/Output whitening : XOR with subkeys
  • Key Schedule
    • simple
    • shares the same part of its procedure with encryption
camellia for 128 bit keys
Camellia for 128-bit keys

subkey

key

plaintext

F

S1

Bytewise

Linear

Transfor-

mation

S4

F

S3

F

S2

FL

FL-1

S4

F

S3

key schedule

FL

FL-1

F

S2

S1

F

Si:substitution-box

ciphertext

camellia for 192 256 bit keys
Camellia for 192/256-bit keys

subkey

key

plaintext

F

S1

Bytewise

Linear

Transfor-

mation

S4

F

S3

F

S2

FL

FL-1

S4

F

S3

key schedule

FL

FL-1

F

S2

S1

F

Si:substitution-box

FL

FL-1

ciphertext

security of camellia
Security of Camellia
  • Encryption/Decryption Process
    • Differential and Linear Cryptanalysis
    • Truncated Differential Cryptanalysis
    • Truncated Linear Cryptanalysis
    • Cryptanalysis with Impossible Differential
    • Higher Order Differential Attack
    • Interpolation Attack
security of camellia cont
Security of Camellia (Cont.)
  • Key Schedule
    • No Equivalent Keys
    • Slide Attack
    • Related-key Attack
  • Attacks on Implementations
    • Timing Attacks
    • Power Analysis
conclusion
Conclusion
  • High level of Security
    • No known cryptanalytic attacks
    • A sufficiently large security margin
  • Efficiency on a wide range of platforms
    • Small and efficient H/W
    • High S/W performance
    • Performs well on low-cost platforms
    • JAVA
standardization activities
Standardization Activities
  • IETF
    • Submitted Internet-Drafts
      • A Description of the Camellia Encryption Algorithm
        • <draft-nakajima-camellia-00.txt>
      • Addition of the Camellia Encryption Algorithm to Transport Layer Security (TLS)
        • <draft-ietf-tls-camellia-00.txt>
standardization activities cont
Standardization Activities (Cont.)
  • ISO/IEC JTC 1/SC 27
    • Encryption Algorithms (N2563)
  • CRYPTREC
    • Project to investigate and evaluate the cryptographic techniques proposed for the infrastructure of an electronic government of Japan
  • WAP TLS
  • Adopted in some Governmental Systems