Phát triển một số phương pháp bảo mật và xác thực thông tin tr tiếng anh

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INTRODUCTION
1.Imperative necessity of the Theme
Security and safe assurance on data information is a question of the
day which is concentrated on research by scientists. This is a wide subject
concerning to many fields. In fact, maybe having many methods
implemented for safe assurance on data information. Many experts focusing
on research and finding every solutions to ensure safety, security for system,
especially computer network systems in state agencies, companies,
industrial groups. If no having any auxiliary protection as well as data
encryption, Internet environment is not really a safe place to exchange data
and secret information documents. In order to ensure information safety for
computer networks, the most effective solution is use cryptography.
Cryptography solutions will ensure all of three requirements which are - data
secret, data intect check and information Authentication.
2. Necessity of information authentication and security
Nowadays, cryptography has already become a question of the day
because of its applicability. With the approach as above, in order to meet
higher demands of applications therefore research on security method and
information authentication on new tendency are essential. Moreover, in the
condition, traditional encryption algorithms were proved which are weak or
have gaps or are unsuitable in applications then the new tendency is more
essential.
Encrypt after all is to satisfy two main requests as follows:
-Use to hide contents of plaintexts: To ensure that, only legal owner
of information just has right to access information, in other words is against
to access with incorrect right.
-Make elements confirm information: Ensure information
circulating in the system to legal receivers to be authentic.Organize
electronic signature outlines, ensure without fade phenomenon, impostors

send information in the internet.
Cryptographies are publicized encryption/decryption algorithm
whether secret-key cryptography or public-key cryptography aslo only


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applied in trade is main. Nowadays algorithm is mainly interesting in a key
code space which must be big enough and encryption algorithm must be
secret by hardening modules of encryption and decryption.
3. Domestic and internatonal research situation
For learning research relating to safety and information security,
domestic researches such as the group of Prof., Dr. Nguyen Binh [6]; (Posts
and Telecommunications Institute of Technology), the group of Ass Prof.,
Dr. Nguyen Hieu Minh [4] (Academy of cryptography) , the group of Dr.
Luu Hong Dung [3] (Academy of military techniques), Bui Van Phat and
Pham Huy Dien [5] (Academy of Mathematics- Vietnam Academy of
Science and Technology), the group of Dr. Thai Thanh Tung (Hanoi Open
University) and the group of Dang Minh Tuan, Nguyen Anh Viet (Academy
of Military Science and Technology)…
Abroad having many research themes on safety and information
security. Specific: in 1983, K.Nakamura and K. Itakura [36] put forth some
concepts on safety and information security. In 1976 Diffie and Hellman, in
the article “New Directions in Cryptography” [65] mentioned some concepts
on safety and information security. In 1978, in the article “A Method for
Obtaining Digital Signatures and Public- key Cryptosystems” [57] R.
Rivest, A. Shamir [11] has just put forth a cryptography sketch, which is
based on difficult problem on analysing factor, called as RSA and used up to
now.
The above domestic and abroad research results show that security

and information authentication in the internet are very important and
essential in new situation.
4. Settled matters in the dissertation
With general analysises on realilty of solutions on security and
information authentication, strong points, weak points and developmental
trend on cryptography nowadays, for security demand by fact cryptography
of services and users, the selected heading of the dissertation is research,
improve methods of security and information authentication in the internet,
which meet demand of the society in the digital era.
Problems are proposed to solve in the dissertation


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In chapter 2 of the dissertation which expresses an algorithm,
combines row encryption and public-key encryption to encrypt texts. This
combination does not need to exchange secret key, only need to use publickey encryption which can send to public channel with a safe way. Therefore,
the dissertation concentrates on solving public-key encryption algorithm
primarily, in order to settle problems which the previous algorithms have not
mentioned yet so that key space is big enough for ensuring safety and
researching to put forth a new encryption algorithm.
In this dissertation, The post-doctoral fellow proposes block encryption
algorithm to improve safety of code by increasing the length of key and
permit users who can customize with one’s demand to self-confirm the level
of security and implementation time of algorithm.
Chapter 3 of the dissertation research about collective digital-signature
sketch which is based on advanced security system having many advantages
and being a trend to become high common utilization which is formatting
security system.
Chapter 4 of the dissertation is a part of installation, compares proposed

stretches with ready stretches. In order to prove proposals which are correct.
5. Research purpose
The purpose of the Dissertation is just to improve and propose some
modules and sketches which are based on ready algorithms and digital
signature sketch based on a formatting security system is a new security
system which is a trend using this security system in the digital era,
especially in the context Vietnam is promoting to develop electronic
government.
6. Research scope and object and research method
6.1. Research object: Cryptography algorithms, ID-Based security system…
6.2. Research scope: Security key cryptography algorithms, popular
security systems having high common utilization as ID-Based security
system.
6.3. Research methods: Research methods are: Analysis method,
comparison, synthesis and result appreciation on experimental soft-ware.


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7. Research duty
Overview research about algorithms of secret key and public-key,
information authentication sketches based on digital signature.
- Propose some improved encrypt sketches and some advanced
authentication sketches.
- Deploy experiment to verify the rightness of sketches which the
author of the dissertation proposed.
8. Science signification and reality
Methods and sketches proposed in the dissertation are applied in
fact which will contribute to make selection opportunities in order to ensure
information safety for organizations and individuals who have demand.

These are researches which are suitable for devices limited about resources,
need to change keys permanently but still ensure encrypt speed and decrypt
and certify exchanged reports.
9. New contributions of the dissertation
9.1. Part for information security
- Security sketch with One Time Pad OTP(One Time Pad)
- Security sketch proposal is based on ARX algorithm.
9.2. Part for information authentication
- Proposing the signature number scheme based on proxy identifier
- Proposing a collective digital signature scheme based on linear pairs
- Build a new digital signature scheme based on the cryptosystem
- Improved blind digital signature scheme based on Elliptic curves

Chapter 1: OVERVIEW ABOUT SAFETY AND INFORMATION


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1.1. Information security
Nowadays, information becomes one of the most precious resources
of many nations, specially in the context of globalizing trend and knowledge
economy development. Protecting information and ensuring the
environment to work with this resource which are essential duties, they play
an important role because more and more people take part in exploiting and
supplying information on that.
With strong development of information technology, specially
development of the Internet, more and more information are kept on
computers and send in the Internet. And therefore appearing demands about
information security and safety. Can classify the safe model of information
security with two main ways as follows [7]:

+)Protecting information during the process of transmitting
informaton in the network.
+)Protecting computer system, and computer network, from every
penetrations to sabotage from outside.
Therefore the theme of the dissertation research about some methods
of information authentication and security in the network to put forth some
more positive solutions for this matter.
1.2. Information protection during the process of conveying information
Information is kept on various forms of other material like being
carved on stones, being written on papers, on cartons, on magnetic tapes, on
magnetic disks, on hardware disks, on memory card,…. Main information is
all of things to bring knowledge to human what human can be aware.
Human always have demands on collecting information with different ways:
reading newspapers, listening radio, watching television, accessing Internet,
communicate with other people with a direct way or through electronic
forums and social network,…
1.2.1. Forms of attack
1.2.2. Security safety for information system
1.2.3. Methods of information protection
1.2.4. Role of cryptography in security in the network
1.3 Information security in database system
1.3.1 Common introduction:


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Database systems (CSDL) at present such as Oracle, SQL/Server,
DB2/Informix which all have ready standard protection tools as format
system and retrieval control. However, This protective methods are hardly
affected before the attacks from inside. In order to protect information from

this threatening, people put forth two solutions:
The simplest solution protects datas in Database system with level of file,
against unauthorized access in Database files by encrypt form.
The second solution, settle encrypt matters in the level of application. This
solution deals with a data encrypt before transmitting datas to Database.
1.3.2 Some models of database security
- Build an intermediary database class.
- Use ready mechanism in Database
1.4. Symmetric cryptography
1.4.1 Definition of some basic concepts on encrypt.
1.4.2 Substitution classical ciphers
1.4.2.1 Ceasar cipher
1.4.2.2 Simple letter table ciphers
1.4.1.3 Playfair cipher
1.4.1.4 Multi-table ciphers
1.4.1.5 Vigenere cipher
1.4.1.6 Kasiski cryptanalysis method
1.5 Permutation classical cipher
Permutation cipher, letters in the plaintext are not replaced by other
letters, only change position, means that encrypt only moves position
relatively among letters in the plaintext. Like this, it hides the plaintext by
changing order of letters, it does not change the letters which are really used.
Therefore, ciphertext has the same frequency allocation which appears
letters as original text. Like this, can cryptanalyse to discover.
1.5.1 Rail Fence cipher
1.5.2 Row moving cipher
1.5.3 Accumulative cipher
1.6 Digital signature
Digital signature is developed from public-key security system. In the
model of digital signatures, the sender will encrypt text by one’s secret key,

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the result will be called as digital signature, after that the sender transfer the
text with signature of the text to the receiver at the same time. The receiver
will use public-key of the sender to decrypt and compare results of the
decryption with the received text, if coinciding then that signature is of the
sender and the text is not amended during the process of sending the text,
contrary to be the digital signature which are invalid, or must not be of the
signer or the text is no longer integrity.
1.7. Modern row cryptography
1.8. Block cryptography
1.8.1. AES [24] introduction
1.8.2 AES algorithm
1.9. Public-key encryption
1.9.1 Reason for using public-key encryption
1.9.2 Necessary features of public-key encryption
1.10. Mathematic basis of the dissertation
1.10.1 Definition of Modulo.
1.10.2 Arithmatic algorithms on Modulo
1.10.3 Greatest common divisor.
10.1.4 Finding inverses
10.1.5Calculating
10.1.6 Prime number
10.1.7 Analysing primary factor
10.1.8 Coprime numbers and GCD
10.1.9 Ferma theorem (small Ferma theorem)
1.10.10 Ole function
1.10.11 Primality test

1.11. Results of chapter 1
In this chapter, The post-doctoral fellow showed existing limits of some
sketches which had at home and abroad, determine specific problems to
apply in pratice that the sketches have not settled yet.
However, still have parts which have not mentioned yet that are secretkey exchanges, sketch applications in different security system…


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Chapter 2 DEVELOPING SOME ENCRYPTION SKETCHES
2.1. Some block code application models
2.1.1 Electronic Codebook - ECB model
2.1.2 Cipher Block Chaining - CBC model
2.1.3 Counter model - CTR
2.1.4 Output Model Feedback - OFB
2.1.5 Model of Cipher Feedback – CFB
2.2. Decryption and encryption sketch proposal basing on the


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cryptography algorithm with One-Time Pad (OTP)
This sketch includes the following processes:
Encryption: A Divides the plaintext into the blocks with size equal to 256
bit. If no being even then must insert a block enough (the way of insertion
like in Hash functions SHA).
Hash plaintext by safe hash function SHA256 with the hash value which has
size as 256 bit. This hash value is chosen to be the beginning OTP key,
called as . This key will be used to be digital signature of sender with a
plaintext. After that, will be chosen to be which is the beginning of OTP key

jet.
is XOR with the first plaintext block to create the first ciphertext
block . The following OTP key, (i=2, 3, ..., n) will be born by the way of
the plaintext block encryption by the security system AES256 with the key
. The keys which have just born to be XOR with the correlative plaintext
block to create the next ciphertext blocks. Set all ciphertext blocks to get the
ciphertext.
Plaintext: M = M1M2…Mn; |Mi| = 256 bit,with I = 1,2,…,n
Initial OTP key:
The next OTP keys: Ki = AES256 (Mi-1, Ki-1), with i =2,3,…,n
Ciphertext blocks: Ci = Mi  Ki , with i = 1, 2,…,n
Ciphertext:
Signing plaintext and conveying information: A signs a plaintext by the
way of encrypting the key OTP K (the hash value of M) is the secret key .
After that continue encrypting by the public-key of B to ensure only B just
read the key K. A sends this ciphertext to B and the ciphertext C:
; of this E is RSA public-key encryption algorithm
Authentication and decryption: B receives the signature of A which was
encrypted by the public key of B and ciphertext C’. B uses one’s secret key
and the public-key of A to decrypt into a chain of bit which is temporarily
called as . After that, B hash the cipher text C’and gain a chain which is
temporarily called as Compare with If they coincide each other then B
affirms that A is maily the sender to, of this is the beginning OTP key to
decrypt the ciphertext . B divide the ciphertext C into blocks with the size
256 bit, after that do the same as the encryption process of A to get a
plaintext.


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If then implement
C=C1C2….Cn with |C1| = 256 bit, with i = 1, 2, …, n
Ki = AES256 (Ci-1, Ki-1), with i=2, 3,….,n
Blocks of plaintext:Mi = CiKi
with i=1, 2, …,n
Plaintext:
2.3. Symmetric key encryption sketch proposal basing on ARX encryption
design technique
A, Idea:
This improved symmetric key encryption algorithm only uses
three basic operations, those are modulo addition operation, bit round shift
operation and Exclusive-OR bit addition operation. Besides, the length of
secret key and the number of encryption loops can be changed which depend
on requirements about density of senders. Moreover, the length of
ciphertexts which are twice as long as the length of plaintext, therefore will
increase safety. Round shift operations depend on proposed datas which are
also used in the process of encryption, decryption and key bearing to raise
disturbance and diffusibility.
B, Improvement algorithm:
Key bearing progress
The swap key has a length of a plaintext block and is calculated by the
formule , in which is length of plaintext block.
The loop keys have the same lengths. Each loop uses a key, bearing loop
keys to implement a process of reiteration. Each loop bears a key, a number
of sub-keys are born equal to the number of loops of the encryption process.
The main key is input for the first loop of key-bearing cycle and the
previous reiteration output is the next reiteration input.
Rotation depends on the data which is based on bit which is least
signification (these bits are determined rotation direction) of main-key
change and sub-keys . In which the first bit determines a rotation direction,

remaining bits determine a number of bits of needing rotation.


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Encryption process
The encryption process is proposed with three stages. In order to be
convenient for a descriptive process, we will suppose the length of the
plaintext block which is 128 bit. The first plaintext block needs to encrypt
which will be extended up double, after that impletmenting loops and at last
carry out a two-phase swap.
The following detail description of three stages of encryption process.
1st Stage: Extend a plaintext block. This block is extended up to double as
256 bit and moved to the input of the first loop.
2nd stage: Rotation depends on datas
Functions in loops: Each loop all have inputs which are an encryption data
block and a loop key .
Finish the loop we get a cipher of the plaintext block. The size of the cipher
is twice as long as the size of the initial plaintext block.
3rd Stage: a 2-phase swap function
This function uses to permute bits with the key due to incorporation of
users. This function has two phases:
Each bit resway bit the from 0 into 1 or from 1 into 0.
Decryption process
Decryption process is a opposite process of the encryption process.
Therefore the complexity of decryption is also similar to the complexity of
encryption. Safety of the decryption encryption process get a high level
because of unlinear which is created to thanks to a rotation which is
depended on datas and a number of unfixed loops and even-odd unkeeping
loops. The linear in this process is not sastified with the stacked principle. It

means that the output is not directly proportional to the input. This is a
classical chaotic form which means that can not foresee direction of
rotations and quantity of rotations.
The symmetric key encryption algorithm improves proposals which
can implement with every size of data size of plaintext. But in this proposing
sketch, the algorithm is calculated on the plain block 128 bit and the
accumulated key size 281 bit makes the script with size 256 bit. The
symmetric key encryption algorithm improves this by using operations such
as: Modulo addition, bit rotation and bit addition except for XOR which


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provided a flexibility for users to select block size of plain block and the
number of repetitive revolution in the encryption process. The rotation
depends on datas which are the most important feature of improving
symmetric key encryption algorithm. It creates a strong diffuse on the
plaintext block (means that change of 1 bit in the plaintext block leads to
completely change in the code script block which is created). This proposal
algorithm has a encryption and decryption speed which is faster than other
encryption algorithms, because only must implement basic and simple
operations.
2.4. Conclusion of chapter 2
In this chapter of the dissertation put forth some security methods of
security and encryption sketches which are base on ready-algorithms to
intensify information security in the internet. Nowadays, there are many
various security methods, however, in the scope of the dissertation, the
author only put forth sketches which having high common utility and simple
operations but still ensure safety.
For using the method of One_Time Pad encryption, this method has

the calculation which is exist many keys , each key uses to decrypt which all
give significant scripts. Therefore, getting to run out of keys which don’t
have any signification for One_Time Pad encryption.
For using ARX algorithm then depending on one’s demand which
the users can self-confirm the level of security and the time of performance
of the algorithm.
The proposed encryption sketch settled the weak point which is to
reveal the secret key used for a long time.
Analysises on safety show that applied competence of the improving
sketch which apply completely in fact .
This is also a premise of chapter 3 which states about some methods
of authentication.


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Chapter 3 DEVELOPING SOME DIGITAL SKETCHES
3.1. Collective digital signature and formatting security system
3.1.1. Digital signature concept
3.1.2 Concept of authorized digital signature signatures
3.1.3 The concept of crypto identifier
3.2 Digital signature sketch basing on formatting security system
3.2.1. Definition of linear form
3.2.2. Proposed schema
3.2.1. Definition on linear form
Proposal sketch agaist attacking scripts
Attack script 1
In order to attack to forge assigned collective digital signatures then an
attacker must find out trapdoor of one-way function of Logarit problem on

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Elliptic curved line which means that finding out secret keys of members in
the collective.
When knowing public-key to find out the secret key, an attacker is
conpulsory to have to solve Logarit problem on Elliptic curved line and this
is a difficult problem which is not settled within the time of multinomial.
Attack script 2: An attacker forges the value in signature component,
probability of success is , if is big enough then this probability will be small
unconsiderably
Attack script 3
An attacker forges a digital signature by forging values and however, to do
that need to have to find out the value and to find out this value, the
attacker is compulsory to solve Desultory Logarit Problem on elliptic curved
line and this is a unsolved problem up to now.
3.3. Assigned digital signature sketch basing on formatting security
system
3.3.1. Key bearing
3.3.2. Key separation
3.3.3. Signature of assigner
3.3.4. Signature authentication of assigner
3.3.5. Key bearing for assignee
3.3.6. Assignment check
3.3.7. Assignment key bearing
3.3.8. Assignment signature bearing
3.3.9. Assigned signature authentication
3.4. Collective digital signature sketch basing on linear couple
3.4.1. Linear parallel function
3.4.2. Proposal sketch

3.4.2.1. Collective public-key bearing
3.4.2.2. Collective digital signature bearing
3.4.2.3. Collective digital signature authentication
Algorithms are based on the linear parallel couple
Joining algorithm:
Joining algorithm by a way of extension:
Joining algorithm by a way of rejecting denominator:


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Linear parallel couple making algorithm:
Analysing safety of sketch
Prove through experiment: the group of authors set up a software in Python
3.2 language, which has ability to run on the operating system of Windows,
Linux, Mac OS. Public-key of members is mainly email address as format.
H1 function is set up by calculating to follow the function:
with is a basic point. function is definited as:
The equation is used for elliptic curved line with the form:
3.5. Assigned collective digital signature sketch basing on formatting
security system
3.5.1 Key bearing
3.5.2 Key separating
3.5.3 Signature of assigner
3.5.4 Signature authentication of assigner
3.5.5 Key bearing for assignee
3.5.6 Assigned signature bearing
3.5.7 Authentication of authorized signatures
Proposal sketch against various kinds of attacking multi-composition
collective digital signatures as follows:

A, RMA attacks - Random Message Attacks
B, KMA attacks - Known Message Attacks
C, ACMA attacks - Adaptive Chosen Message Attacks
This is a type of the strongest attack, attackers can be chosen text to sign
which is depended on public-key also as previous digital signatures. Maybe
this performance passes access ability to Oracle function, the sign is
Attack script 1
In order to attack to forge an assigned collective digital signature
then an attacker must find out a trapdoor of one-way function of Logarit
problem on Elliptic curved line which means that finding out secret keys of
members in the collective.
When knowing a public-key to find out the secret key, an attacker is
conpulsory to have to solve Logarit problem on Elliptic curved line and this
is a difficult problem which is not settled within the time of multinomial.


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Attack script 2
An attacker forges the value in signature component, probability of
success is , if is big enough then this probability will be small
unconsiderably
Attack script 3
An attacker forges a digital signature by forging values and
however, to do that need to have to find out the value and to find out this
value, the attacker is compulsory to solve Desultory Logarit Problem on
elliptic curved line and this is a unsolved problem up to now.
3.6. Blind signature improvement on Elipptic curved line
3.6.1 Mathematical basis
3.6.2 Encryption sketch on Eliptic curved line

3.6.2.1 Participants
3.6.2.2 Blind encryption model on Eliptic curved line.
3.6.2.3 Blind encryption
3.6.2.4 Signature verification
3.6.3 Decryption
3.6.4 Blind signature proposal on Elipptic curved line
3.6.4.1 Improvement
3.6.4.2 Rightness demonstration
3.6.5 Security analysis
Nobody can forge legal signatures if no knowing the secret keys of the
signaturers and are also random parameters by the signaturers.
If an attacker wants to calculate then will have to find and .
• 1st Case: Calculate from the equation is a difficult problem, equivalent to
solve ECDLP problem (Desultory Logarit Problem on Elliptic curved line)
• 2nd Case: Calculate w from the equation is a difficult problem, equivalent
to solve ECDLP problem.
In the proposal sketch, if signatures have the compositions:
Of this: , Attackers can not follow blind signatures.
When senders, send the compositions with publicity, signaturers will
calculate the values and have, and , Of this


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Clearly, Seek three indefinitive factors from over two equations which is a
difficult problem; therefore no having any way for signaturers to follow
blind signatures.
3.7. Conclusion of chapter 3
Formatting security system is a public-key encryption security
system, which permit an person using to calculate a public-key from a chain.

In the assigned collective signature sketch, members in the collective
sign in the whole documents, or each member signs in only one part the
documents in order.
The proposal digital signature sketch has a high flexibility, which can
apply in many layers of collective digital signature problem in the reality. In
the proposal sketch which improves the sketch, to show that the encryption
signature program which ensured security in some fixed cases.


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Chapter 4 SOME EXPERIMENTAL RESULTS
4.1 OTP ENCRYPTION EXPERIMENTAL INSTALLATION
The software program illustrates the algorithm which implemented
functions:
-Encrypt every input messages by the cryptography algorithm with
One Time Pad (OTP), implement encryption, decryption and display results.
-Compare other algorithms with faster speech when having the same input
messages.
- The research puts forth the methods using OTP algorithm with an object of
increasing safety, increasing encryption and decryption speed
and
decreasing the length of key, and supplementing authentication
compositions.
4.2 EXPERIMENT WITH ARX ALGORITHM
The data encryption shows an output of key making process, sample
data encryption, input key encryption to make a main key.
4.3 ID – BASED EXPERIMENT INSTALLATION
- The Collective digital signature experiment program on ID-Based security
system which is built on Python programming language.

- PyQT5 software installation supports an interface programming.
The function of the programme: puts forth signatures of assigners when they
can not sign. Therefore the assigners will assign for a collective to sign to
make assigned signatures.
Of this:
+ : secret parameter
+ : is bearing element
+ ID_Assignment: is format of assigner to sign. The input is a unlimited
chain.
+ ID_1st Signer : is format of the 1st assignee to sign (the input is a unlimited
chain - text form)
+ ID_2nd signer: is format of the 2nd assignee to sign (the input is a unlimited
chain - text form)


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+ ID_3th signer: is format of the 3th assignee to sign (the input is a unlimited
chain - text form)
+ Messages need signing: are messages which assigners assign for
assignees to sign on behalf of them.
+ Collective digital signatures: are assigned signatures after the programme
calculates.
Appreciation from mathematic basis to pratice:
- Because the result of Hash function SHA-256 is an extremely big, up to
therefore the calculation process will last in a long time for the programme
of using three hash functions
- The process gives a result which must wait some seconds or up to minites,
depend on the processing set of the computer running this programme.

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CONCLUSION AND RECOMMENDATIONS
1. Conclusion
Nowadays, with the great development of information technology
and communications which brought back many applications in face and gain
satisfactory results. In order to meet security demands and apply encryption
technique, scientists often research to propose, improve algorithms to be
suitable with new situations. Specially, solving specific problems which are
in fact, in this dissertation the post-doctoral fellow puts forth proposals to
improve some methods of security and information authentication which are
based on ready-algorithms and the new security system which is tendency of
the industrial revolution 4.0
With the stated content in the Dissertation, with the gained results in
the promulgated science works of the post-doctoral fellow which show that
the Dissertation has met demands of the proposed objects, solutions and
direction approaching of the Dissertation which are suitbale with practice.
The Dissertation proposed four sketches, improved three algorithms and
built a new sketch which expresses in chapter 3 and chapter 4. The sketches
and the improvements permit to meet real demands with a flexible way for
users.
New contributions of the theme of the dissertation:
+) Part for information security
Improve the block algorithm to be based on the non-linear feedback
shift registers.
Propose sketches of encryption and decryption to be based on the
cryptography algorithm with One-Time Pad (OTP);
Propose a symmetric key encryption sketch to based on ARX algorithm;
+) Part for information authentication

Propose assigned digital signature sketches to be based on the
formatting security system.
Propose the collective digital signature sketch to be based on the linear
parallel couple.


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Build a new signature sketch to be based on the formatting security
system.
Improve the blind digital sketch.
2. Petition on the next research orientation
In the future, the post-doctoral fellow continues researching deeplier
about ways of exchanging secret key on the public channel or exchanging
one’s own channel.
Go on researching the length of the key when writing clearly as a
big text.
Research a collective model which is for almost of other security
systems and combine with other signature forms: multi-composition
collective signature with construction…
Research solutions which combine to use ID-Based security system
for encryption and traditional public-key system to supply digital signatures
to propose new algorithms which are more effective for other topical
algorithms in the field of safety and information security.
Research to combine between blind signatures on ID-Based security
system.

PUBLICATIONS RELATED TO THE DISSERTATION

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[CT1] Nguyen Duc Toan, Nguyen Van Tao,(2016), “ Design of the creation
pseudo ranges maximum cycle”, Journal of Science and Technology,
Nature Science - Technology – Thai Nguyen University, Volume 159,
No. 14, page 115-118, ISSN 1859-2171.
[CT2] Nguyen Duc Toan, Bui The Hong, Nguyen Van Tao, Tran Manh
Huong, (2016), “Encryption and authentication message by cipher one
time pad (OTP)”, Proceedings of the 9th National Conference of
Fundamental and Applied
Information Technology Research
(FAIR’9), ISBN 978-604-913-472-2, page 284-289.
[CT3] Nguyen Duc Toan, Nguyen Van Tao,(2016), “Combination treatment
method code OTP and block cipher to encrypt – decrypt the mesage”,
The 19st National Conference on Electronics, Communications and
Information Technology, REV/ECIT 2016, Subject: 4-1.
[CT4] Nguyen Duc Toan, Nguyen Van Tao, Bui The Hong, (2017), “One
quality assessment criteria pseudorandom bit sequence”, Journal of
Science and Technology, Nature Science - Technology – Volume 162,
No. 02, page 47-50 - Thai Nguyen University, ISSN 1859-2171.
[CT5] Nguyen Duc Toan, Bui The Hong, Nguyen Van Tao,(2017), “About
one modifed symmetric blok cipher algorithm” Proceedings of the
10th National Conference of Fundamental and Applied Information
Technology Research (FAIR’10), ISBN 978-604-913-614-6.
[CT6] Toan Nguyen Duc, Hong Bui The, (2017), “Building scheme to the
Elgamal Algorithm”, International Journal of Mathematical Sciences
and Computing, ISSN 2310-9033, IJMSC Vol. 3, No. 3, tr 39 - 49,
Hong Kong.
[CT7] Nguyen Duc Toan, Dang Minh Tuan, (2017), “Building a delegated
collective digital signature model based on ID-Based cryptosystem”,

Conference on Education Science and Technologies- CEST 2017,
ISBN 978-604-80-2642-4, page 193-198.


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[CT8] Nguyen Duc Toan, Dang Minh Tuan, (2017),“A Design new Bilinear
Mapping Multisignature Scheme”, Journal of science & technology
on information and communications – Ministry of information and
communications - Posts and Telecommunications Institute of
Technology No. 02&03, ISSN 2525-2224, page 92-96.
[CT9] Dang Minh Tuan, Le Xuan Duc, Nguyen Xuan Tung, Nguyen Duc
Toan,(2017), “Design a new ID-Based multisignature scheme”,
Journal of Military science and technology Volume No. 52, ISSN
1859-1043, page121-125.