COMPARISON BETWEEN DES , 3DES ,

RC2 , RC6 , BLOWFISH AND AES

MILIND MATHUR milindmathur04@gmail.com +91 9622245134

AYUSH KESARWANI ayush.kesarwani@gmail.com +91 9796624282

ABSTRACT -If the confidentiality of the information of very high value, it should be protected. If you want to stop the

unauthorised disclosure or alteration of the information, secure it. With the fast change in technologies today, more and more

multimedia data are generated and transmitted, leaving our data vulnerable to be edited, modified and duplicated. Digital

documents will be faced by many threats as they are also easy to copy and distribute. Because of the significance, accuracy

and sensitivity of the information it is a big security and privacy issue, making it necessary to find appropriate solution.

Security and privacy has become an important concern. Cryptography is a technique which is used to protect the important

data. Encryption is the science of changing data so that it is unrecognisable and useless to an unauthorised person.

Decryption is changing it back to its original form. This paper presents the comparison in performance of six most useful

algorithms: DES, 3DES, AES, RC2, RC6 and BLOWFISH . Performance of different algorithms is different according to data loads.

Index Terms—Data Encryption Standard, Triple Data Encryption Standard, Advance Encryption Standard,

Rivest- Shamir-Adleman , RC2 , RC6 , Blowfish.

1. INTRODUCTION

Cipher text is an art of protecting information

by encrypting it into an unreadable. This information can

only be possessed by those who possess the secret key

that can decipher (or decrypt) the message into original

form. Cryptography is a vital part of securing private data

and preventing it from being stolen. In addition to

concealing the real information stored in the data,

cryptography performs other critical security

requirements for data including integrity, repudiation,

authentication and confidentiality.

Today cryptography is not just limited to prevent

sensitive military information, but is one of the critical

components of the security policy of any organization

and is considered as an industry standard for providing

information trust, security, electronic financial

transactions and controlling access to resources.

In the World War II for instance cryptography played an

imperative role that gave the allied forces the upper hand,

and helped them in winning the war. They were able to

dissolve the Enigma cipher machine which the Germans

used to encrypt their military secret communications.

Plaintext is the Original data that to be transmitted or

stored, which is readable and understandable either by a

computer or by a person. Whereas the ciphertext, which

is unreadable, neither machine nor human can make out

some meaning out of it until it is decrypted.

Cryptosystem is a system or product that provides

encryption and decryption. Cryptosystem uses an

encryption algorithms which determines how simple or

complex the encryption process will be. In encryption,

key is a piece of information which states the particular

conversion of plaintext to ciphertext, or vice versa during

decryption. The larger key space the more possible keys

can be created . The strength of the encryption algorithm

banks on the length of the key ,secrecy of the key , the

initialization vector, and how they all work together.

Depending on the algorithm, and length of the key, the

strength of encryption can be measured. There are two

encryption/decryption key types: In some of encryption

technologies when two end points need to communicate

with one another via encryption, they must use the same

algorithm, and in the most of the time the same key, and

in other encryption technologies, they must use different

but related keys for encryption and decryption purposes.

Cryptography algorithms are either symmetric

algorithms, which use symmetric keys (also called secret

keys), or asymmetric algorithms, which use asymmetric

keys (also called public and private keys).

2. PUBLIC-KEY CRYPTOSYSTEM The development of public key cryptography is the

greatest revolution in the entire history of cryptography.

With public key techniques, each user has two different

keys, one of them is made available to the public and the

other is kept undisclosed. One of the keys is used to

encrypt a message, and the other is used to decrypt the

message. If Carol wants to send a secret message to Bob,

for example, she looks up Ben's public key and uses it to

encrypt the message. Because Ben's public key cannot

undo the encryption process, no one who intercepts the

message can read it. Only Ben, who possesses the secret

key corresponding to his public key, can read the

message. Carol never has to meet Ben out of the hearing

of others to exchange keys or passwords; this is a

substantial improvement over older encryption methods

in which an exchange of private keys was necessary. This

system can also be used as a means for Ben to be sure a

message comes from Carol. If Carol wants to sign a

message, she can encrypt it with her private key. When

Ben receives an encrypted message which purports to be

from Carol, he can obtain Carol’s public key and decrypt

the message. If a readable message emerges, Ben can

have confidence that the message came from Carol,

because Carol’s public key would only properly unlock a

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message which was locked with her private key (known

only to Carol). Figure-1 illustrates the public-key

encryption process.

Figure-1 public key encryption.

This type of encryption is much better than traditional

symmetric Ciphers. It means that the addressee can make

their public key widely available- anyone wanting to

send them a message uses the algorithm and the

recipient's public key to do so. An eavesdropper may

have both the algorithm and the public key, but will still

not be able to decrypt the message. Only the recipient,

with the private key can decrypt the message.

This makes it possible for Carol and Ben to simply send

their public keys to one another, even if the channel they

are using to do so is insecure. It is not a problem that

another person Steve now gets a copy of the public keys.

If Carol wants to send a secret message to Ben, she

encrypts the message using Ben's public key. Ben then

takes his private key to decrypt the message. Since Steve

does not have a copy of Ben's private key, he cannot

decrypt the message. Of course this means that Ben has

to carefully guard his private key. With public key

cryptography it is thus possible for two people who have

never met to securely exchange messages.

A disadvantage of public-key algorithm is that they are

more computationally intensive than symmetric

algorithms, and therefore encryption and decryption take

longer. This may not be significant for a short text

message, but certainly is for bulk data encryption.

3. CRYPTOGRAPHY WITH BLOCK CIPHER

In Cryptography, a block cipher is a symmetric key

cipher which operates on fixed-length groups of bits,

termed blocks, with an unvarying transformation. When

encrypting, a block cipher might take a (for example)

128-bit block of plaintext as input, and outputs a

corresponding 128-bit block of cipher text. The exact

transformation is controlled using a second input — the

secret key. Decryption is similar: the decryption

algorithm takes, in this example, a 128-bit block of

cipher text together with the secret key, and yields the

original 128-bit block of plaintext. To encrypt messages

longer than the block size (128 bits in the above

example), a mode of operation is used. Block ciphers can

be contrasted with stream ciphers; a stream cipher

operates on individual digits one at a time and the

transformation varies during the encryption. The

distinction between the two types is not always clear-cut:

a block cipher, when used in certain modes of operation,

acts effectively as a stream cipher as shown in Fig 2.

Fig 2. Stream Cipher.

An early and highly influential block cipher design is the

Data Encryption Standard (DES). The (DES) is a cipher

(a method for encrypting information) Selected as an

official Federal Information Processing Standard (FIPS)

for the United States in 1976, and which has

subsequently enjoyed widespread use internationally.

The algorithm was initially controversial, with classified

design elements, a relatively short key length, and

suspicions about a National Security Agency (NSA)

backdoor. DES consequently came under intense

academic scrutiny, and motivated the modern

understanding of block ciphers and their cryptanalysis.

DES is now considered to be insecure for many

applications. This is chiefly due to the 56-bit key size

being too small; DES keys have been broken in less than

24 hours. There are also some analytical results which

demonstrate theoretical weaknesses in the cipher,

although they are infeasible to mount in practice. The

algorithm is believed to be practically secure in the form

of Triple DES, although there are theoretical attacks. In

recent years, the cipher has been superseded by the

Advanced Encryption Standard .

3.1 Data Encryption Standard (DES)

56-bit key is used in DES and 16 cycle of each 48-bit sub

keys are formed by permuting 56-bit key. Order of sub

keys is reversed when decrypting and the identical

algorithm is used. Block size of 64-bit is made from L

and R blocks of 32-bit.

3.2 Triple DES

Triple DES simply extends the key size of DES by

applying the algorithm three times in succession with

three different keys. The combined key size is thus

168 bits (3 times 56), beyond the reach of brute-force.

3.3 Advanced Encryption Standard (AES) / Rijndael

Advanced Encryption Standard, is a symmetric block

cipher that can encrypt data blocks of 128 bits using

symmetric keys 128, 192, or 256. AES encrypt the data

blocks of 128 bits in 10, 12 and 14 round depending on

the key size. Brute force attack is the only effective

attack known against this algorithm. AES encryption is

fast and flexible.

3.4 RSA ALGORITHM The RSA Algorithm was named after Ronald Rivest, Adi

Shamir and Leonard Adelman, who first published the

algorithm in April, 1977 . The RSA Algorithm is public

key cryptography and it ensures that whilst an encryption

key is publicly revealed, it does not reveal the

corresponding decryption key. Typical encryption

techniques use mathematical operations to transform a

message (represented as a number or a series of numbers)

into a cipher text.

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3.5 RC2

RC2 is a symmetric block cipher that operates on 64 bit

(8 byte) quantities. It uses a variable size key, but 128 bit

(16 byte) key would normally be considered good. It can

be used in all the modes that DES can be used.A

proprietary algorithm developed by RSA Data Security,

Inc.,. The algorithm expands a single message by up to 8

bytes. RC2 is a block cipher that encrypts data in blocks

of 64 bits.

3.6 RC6

RC6 proper has a block size of 128 bits and supports key

sizes of 128, 192 and 256 bits. RC6 is very similar to

RC5 in structure, using data-dependent rotations,

modular addition and XOR operations; in fact, RC6

could be viewed as interweaving two parallel RC5

encryption processes. However, RC6 does use an extra

multiplication operation not present in RC5 in order to

make the rotation dependent on every bit in a word, and

not just the least significant few bits.

3.7 BLOWFISH

Blowfish is 64-bit block cipher- used to replace DES

algorithm. Ranging from 32 bits to 448 bits, variable-

length key is used. Variants of 14 round or less are

available in Blowfish. Blowfish is unpatented and

license-free and is available free for all uses. Blowfish is

one of the fastest block ciphers developed to date.

Blowfish suffers from weak keys problem, still no attack

is known to be success.

4. COMPARISON BETWEEN AES, 3DES , DES ,

RC2 , RC6 AND BLOWFISH

Advance Encryption Standard (AES) and Triple DES

(TDES or 3DES) are commonly used block ciphers. By

design AES is faster in highlight their differences in

terms each of 16 rounds. For example, switching bit 30

with 16 is much simpler in hardware than software. DES

encrypts data in 64 bit block size and uses effectively a

56 bit key. 56 bit key space amounts to approximately 72

quadrillion possibilities. Even though it seems large but

according to today’s computing power it is not sufficient

and vulnerable to brute force attack. Therefore, DES

could not keep up with advancement in technology and it

is no longer appropriate for security. Because DES was

widely used at that time, the quick solution was to

introduce 3DES which is secure enough for most

purposes today.3DES is a construction of applying DES

three times in sequence. 3DES with three different keys

(K1, K2 and K3) has effective key length is 168 bits (The

use of three distinct key is recommended of 3DES.).

Another variation is called two-key (K1 and K3 is same)

3DES reduces the effective key size to 112 bits which is

less secure. Two-key 3DES is widely used in electronic

payments industry. 3DES takes three times as much CPU

power than compare with its predecessor which is

significant performance hit. AES outperforms 3DES both

in software and in hardware .The Rijndael algorithm has

been selected as the Advance Encryption Standard (AES)

to replace 3DES. AES is modified version of Rijndael

algorithm. Advance Encryption Standard evaluation

criteria among others was:

• Security

• Software & Hardware performance

• Suitability in restricted-space environments

• Resistance to power analysis and other implementation

attacks.

Rijndael was submitted by Joan Daemen and Vincent

Rijmen. When considered together Rijndael’s

combination of security, performance, efficiency,

implement ability, and flexibility made it an appropriate

selection for the AES. By design AES is faster in

software and works efficiently in hardware. It works fast

even on small devices such as smart phones; smart cards

etc. AES provides more security due to larger block size

and longer keys. AES uses 128 bit fixed block size and

works with 128, 192 and 256 bit keys. Rijndael algorithm

in general is flexible enough to work with key and block

size of any multiple of 32 bit with minimum of128 bits

and maximum of 256 bits. AES is replacement for 3DES

according to NIST both ciphers will coexist until the

year2030 allowing for gradual transition to AES. Even

though AES has theoretical advantage over 3DES for

speed and efficiency in some hardware implementation

3DES may be faster where support for 3DES is mature.

A user of RSA creates and then publishes the product of

two large prime numbers, along with an auxiliary value,

as their public key. The prime factors must be kept

secret. Anyone can use the public key to encrypt a

message, but with currently published methods, if the

public key is large enough, only someone with

knowledge of the prime factors can feasibly decode the

message. Whether breaking RSA encryption is as hard as

factoring is an open question known as the RSA

problem. RSA implemented two important ideas:

1. Public-key encryption. This idea omits the need for a

―courier‖ to deliver keys to recipients over another secure

channel before transmitting the originally-intended

message. Everyone has their own encryption and

decryption keys.

2. Digital signatures. The receiver may need to verify

that a transmitted message actually originated from the

sender (signature), and didn’t just come from there

(authentication).

This is useful for electronic transactions and

transmissions, such as fund transfers. The security of

RSA algorithm has so far been validated and checks can

be electronically signed with RSA. RSA can be applied

to any electronic system that needs to have a

cryptosystem implemented.

RC6 is a new block cipher submitted to NIST for

consideration as the new AES. The design of RC6 began

with a consideration of RC5 as a potential candidate for

an AES submission. The philosophy of RC6 is to exploit

operations that are efficiently implemented on modern

processors. RC6 takes advantage of the fact that 32-bit

integer multiplication is now efficiently implemented on

most processors. For most applications, an

implementation of RC6 in software is probably the best

choice. RC6 could be written with well under 256 bytes

of code each for the tasks of key setup, block encryption,

and block decryption. Unlike many others, RC6 does not

use look-up tables during encryption. Means RC6 code

and data can readily fit within today’s on-chip cache

memory, and typically do so with room to spare. RC6 is

a secure, compact and simple block cipher. It offers good

performance, considerable flexibility, allows analysts to

quickly refine and improve our estimates of its security.

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5. SIMULATION RESULTS

A. differentiate output results of encryption (Base 64,

Hexadecimal)

Simulation results are given in Fig. 3 and Fig. 4 for the selected

six encryption algorithms at different encoding method. Fig. 2

shows the results at base 64 encoding while Fig. 3 gives the

results of hexadecimal base encoding. We can notice that there

is no significant difference at both encoding method. The same

files are encrypted by two methods; we can recognize that the

two curves almost give the same results.

Fig. 3. Time consumption of encryption algorithm (base 64

encoding)

Fig. 4 Time consumption of encryption algorithm (Hexadecimal

encoding)

B- The effect of changing packet size for cryptography

algorithm on power consumption. -Encryption of different

packet size

Encryption time is used to calculate the throughput of an

encryption scheme. It indicates the speed of encryption. The

throughput of the encryption scheme is calculated by dividing

the total plaintext in Megabytes encrypted on the total

encryption time for each algorithm in. As the throughput value

is increased, the power consumption of this encryption

technique is decreased.

TABLE 3

Comparative execution times (in milliseconds) of encryption

algorithms with different packet size

Fig. 5 Throughput of each encryption algorithm

(Megabyte/Sec)

Simulation results for this compassion point are shown

Fig. 4 and Table1 at encryption stage . The results show

the superiority of Blowfish algorithm over other

algorithms in terms of the processing time. Another point

can be noticed here; that RC6 requires less time than all

algorithms except Blowfish. A third point can be noticed

here; that AES has an advantage over other 3DES, DES

and RC2 in terms of time consumption and throughput. A

fourth point can be noticed here; that 3DES has low

performance in terms of power consumption and

throughput when compared with DES. It requires always

more time than DES because of its triple phase encryption

characteristics. Finally, it is found that RC2 has low

performance and low throughput when compared with

other five algorithms in spite of the small key size used.

-decryption of different packet size

TABLE 4

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Fig. 6 Throughput of each decryption algorithm

(Megabyte/Sec)

Simulation results for this compassion point are shown

Fig. 5 and Table2 decryption stage. We can find in

decryption that Blowfish is the better than other

algorithms in throughput and power consumption. The

second point should be notice here that RC6 requires less

time than all algorithms except Blowfish. A third point

that can be noticed that AES has an advantage over other

3DES,DES RC2.The fourth point that can be considered is

that RC2 still has low performance of these algorithm.

Finally, Triple DES (3DES) still requires more time than.

6.CONCLUSION

This paper presents a performance evaluation of selected

symmetric encryption algorithms. The selected algorithms are

AES, DES, 3DES, RC6, Blowfish and RC2. Several points

can be concluded from the simulation results. First; there is

no significant difference when the results are displayed

either in hexadecimal base encoding or in base 64 encoding.

Secondly; in the case of changing packet size, it was

concluded that Blowfish has better performance than

other common encryption algorithms used, followed by

RC6. Third; in the case of changing data type such as

image instead of text, it was found that RC2, RC6 and

Blowfish has disadvantage over other algorithms in terms

of time consumption. Also, we find that 3DES still has

low performance compared to algorithm DES. Finally -in

the case of changing key size – it can be seen that higher key

size leads to clear change in the battery and time consumption.

7.ACKNOWLEDGEMENT

Thanks in advance for the entire worker in this project, and the

people who support in any way, also I want to thank SHRI

MATA VAISHNO DEVI UNIVERSITY for the support they

offered, also I would like to extend our deep apparitions and

thanks Mr. Rakesh Kumar Jha for his support.

8.REFFERENCES

[1] Ruangchaijatupon, P. Krishnamurthy, ''Encryption

and Power Consumption in Wireless LANs-N,’’

The Third IEEE Workshop on Wireless LANs -

September 27-28, 2001- Newton, Massachusetts.

[2] Hardjono, ''Security In Wireless LANS And MANS,''

Artech House Publishers 2005.

[3] W.Stallings, ''Cryptography and Network Security 4th

Ed,'' Prentice Hall , 2005,PP. 58-309 .

[4] Coppersmith, D. "The Data Encryption Standard (DES)

and Its Strength Against Attacks."I BM Journal of

Research and Development, May 1994,pp. 243 -

250.

[5] Bruce Schneier. The Blowfish Encryption Algorithm

Retrieved October 25, 2008,

http://www.schneier.com/blowfish.html

[6] Shasi Mehlrotra seth, Rajan Mishra ― Comparative

Analysis of Encryption Algorithms For Data

Communication‖, IJCST Vol. 2, Issue 2, June 2011

[7] Daemen, J., and Rijmen, V. "Rijndael: The Advanced

Encryption Standard."D r. Dobb's Journal, March

2001,PP. 137-139.

[8] N. El-Fishawy , "Quality of Encryption Measurement

of Bitmap Images with RC6, MRC6, and Rijndael

Block Cipher Algorithms", International Journal of

Network Security, , Nov. 2007, PP.241–251

[9] K. McKay, ''Trade-offs Between Energy and Security

in Wireless Networks Thesis,''

Worcester

Polytechnic Institute, April 2005.

10] R. Chandramouli, ''Battery power-aware encryption -

ACM Transactions on Information and System

Security (TISSEC),'' Volume 9 , Issue 2

,May.

2006.

[11] S.Hirani, ''Energy Consumption of Encryption

Schemes in Wireless Devices Thesis,'' university of

Pittsburgh, April 9,2003. Retrieved October 1,

2008,

at: portal.acm.org/citation.cfm?id=383768

[12] "A Performance Comparison of Data Encryption

Algorithms," IEEE [Information

and Communication Technologies, 2005.

ICICT 2005. First International Conference ,2006-

02-27, PP.84- 89.

[13] Results of comparing tens of encryption algorithms

using different settings- Crypto++ benchmark- .

Retrieved October 1,

2008, from:

http://www.eskimo.com/~weidai/benchmarks.html

[14] S.Z.S. Idrus,S.A.Aljunid,S.M.Asi, ''Performance

Analysis of Encryption Algorithms Text Length

Size on Web Browsers,'' IJCSNS International Journal

of Computer Science and Network Security,

VOL.8 No.1, January 2008 ,PP 20-25.

[15] A.A. Tamimi, ''Performance Analysis of Data

Encryption Algorithms. Retrieved October 1, 2008

from http://www.cs.wustl.edu/~jain/cse567-

06/ftp/encryption_perf/index.html

[16] A. Sinha and A.P. Chandrakasan, JouleTrack, ''A

Web Based Tool for Software Energy Profiling, ,‖

proceedings of the 38th

Design

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