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A New Biometric ID-Based Cryptography Protocol and Security Analysis Using Petri Nets

27 Jul 2015-

About: The article was published on 2015-07-27 and is currently open access. It has received None citation(s) till now. The article focuses on the topic(s): ID-based cryptography & Petri net.
Topics: ID-based cryptography (61%), Petri net (57%), Security analysis (50%)

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A New Biometric ID-Based Cryptography Protocol
and Security Analysis Using Petri Nets
Dania Aljeaid
School of Science and Technology
Nottingham Trent University
Nottingham, United Kingdom
N0360890@ntu.ac.uk
Xiaoqi Ma
School of Science and Technology
Nottingham Trent University
Nottingham, United Kingdom
xiaoqi.ma@ntu.ac.uk
Caroline Langensiepen
School of Science and Technology
Nottingham Trent University
Nottingham, United Kingdom
caroline.langensiepen@ntu.ac.uk
AbstractThis paper presents a Petri net (PN) approach to
modelling, simulating, and analysing the new protocol we have
proposed. This new protocol is an enhanced authentication
scheme based on a biometric verification mechanism and identity
based cryptography. A formal approach like Petri nets allows one
to represent cryptographic protocols. For the sake of simplicity, a
complex PN model will not be discussed in this paper until all
attacks are demonstrated and the model proved to be secure.
This paper shows how Petri nets are used to model, analyse and
detect flaws in our new protocol. First, our proposed protocol is
modelled without an adversary, and then a generic adversary
model is added to examine all possible adversary behaviours.
Finally we demonstrate how Petri nets can be used to analyse
security threats such as man-in-the-middle attack, reflection
attack, and parallel session attack on this protocol.
Keywords- identity-based cryptosystem; biometrics; security
analysis; cryptographic protocol; Petri nets.
I. INTRODUCTION
Due to the unique characteristics possessed by
cryptographic protocols, analysis and evaluation tend to be
more difficult than normal protocols. Typically cryptographic
protocols, also known as security protocols, tend to inhabit a
complex environment by utilising various cryptographic
mechanisms, such as symmetric and asymmetric encryption,
hash functions, timestamps, and digital signature [1]. For this
reason, Petri nets offer the opportunity to conduct an in-depth
analysis and overcome security vulnerabilities and weaknesses.
Moreover, they simplify the modelling of exchange messages
between nodes and describe behaviour of authentication and
key agreement procedure. A number of researchers have used
Petri nets to model and analyse cryptographic protocols [2 -6].
The structure of this paper is organised as follows. In
Section 2, we briefly review previous works on Petri nets and
our new protocol. In Section 3, we model the client-server
trust model using PN. In Section 4, we add the adversary
entity to the trust model and simulate various attacks using
PN. We then provide a brief discussion on security analysis in
Section 5. Finally, the conclusions are given in Section 6.
II. REVIEW OF RELATED WORK
A. Petri Nets
The concept of the Petri net [7] was introduced in 1962 by
Carl Adam Petri [8]. Petri nets are graphical diagrammatic tools
based on strong mathematical foundations. It is used as a visual
communication aid to model concurrency, synchronisation,
limited resources, sequentially, mutual exclusion and behaviour
in distributed systems [9-11]. A Petri net is defined as a bipartite
directed, weighted graph with two types of nodes called places
and transitions, linked by directed arcs. In other words, a Petri
net must consist of the following components [9-11]:
! A set of places (drawn as circles in the graphical
representation), represent conditions and possible states
of the system.
! A set of transitions (drawn as rectangles or thick bars),
represent a change of state which caused by events or
actions
! A set of arcs (drawn as arrows), connecting a place to
transition and vice versa.
! Tokens (drawn as black dots), occupy places to
represent the truth of the associated condition.
The formal definition of a Petri net is shown in Table 1 [10].
Generally Petri nets focus on specific properties such as
liveness, deadlock, livelock, boundedness and safeness [9-11].
Table 1. Formal Definition of a Petri Net
A Petri net is 5-tuple, PN=(P,T,F,W,M
0
) where:
P={p
1
, p
2
,…,p
m
} is a finite set of places,
T={t
1
,t
2
,…,t
n
} is a finite set of transitions,
F (P X T) U (T X P) is a set of arcs (flow
relations),
W: F " {1, 2, 3,…} is a weight function,
M
0
: P " {0, 1, 2, 3,….} is the initial marking,
P T= ø and P U T ø.
A Petri net structure N=(P, T, F, W) without any specific initial
marking is denoted by N.
A Petri net with the given initial marking is denoted by (N, M
0
).
Petri nets are used in this paper to ensure the soundness of
the protocol analysis. This approach is a very useful tool for
modelling and simulating a range of possible attacks on the
proposed protocol. The key features of using Petri nets can be
summarised as follows:
1. The ability to model the concurrency of the protocol
progress with tokens
2. The ability to model intermediate and final objectives as
places

3. The ability to model transitions as commands and inputs
B. Review of Proposed Protocl
In our previous work [12], we have developed a new
authentication protocol that allows remote mutual
authentication with key agreement. Our new protocol is based
on biometric verification and ID-based Cryptograph [13].
Moreover, the new protocol is aimed to initiate secure
authentication and communication between the client and
server by building a robust mechanism between
communicating parties The proposed protocol may be
described as a two-factor user authentication mechanism and
three-way handshake procedure to establish a reliable
connection and ensure secure data sharing. Our new protocol
consists of four phases: system initialising phase, registration
phase, login phase, and authentication phase. The new protocol
is summarised in Fig. 1 and the notations used for the new
protocol are summarised in Table 2.
Registration
Client C
i
Registration Centre R
i
(1) ID
ci
, PW
ci
, Bio
ci
,
(3) ID
C
i
,
H
4
(.), Enc{}a/Dec{ }a,
f
i
, e
i
, τ, Pr_K
C
i
(2) Computes:
f
i
= H
4
(Bio
ci
)
e
i
= H
4
(ID
ci
||y)H
4
(PW
Ci
||f
i
)
Pr_K
ci
= (x+ H
4
(ID
c
i
))
-1
.P
Login
Client C
i
Server S
i
(1) Enters ID’
C
i
and PW’
C
i
(3) Inputs Bio’
C
i
(5) Computes:
z’
i
= H
4
(PW
C
i
||f
i
)
M
1
=e
i
z’
i
W
1
=r
C
i
. P
M
2
= r
C
i
. Pr_K
C
i
M
3
= M
1
r
ci
k=H
2
(ID
C
i
, T
C
i
, W
1
, M
2
)
(6) C
1=
Enc{ID
C
i
, T
C
i
, W
1
, M
3
,
MAC
k
(ID
C
i
, T
C
i
, W
1
,M
3
)}
a
(2)Verifies the authenticity of ID’
C
i
and
PW’
C
i
(4) Verifies
Accept if d(Bio
C
i
,
Bio
*
C
i
) < τ
Reject if d(Bio
C
i
,
Bio
*
C
i
) τ
Client C
i
Server S
i
Authentication
(5) Decrypts C
2
and verifies M
7
?=
H
4
(M
4
||r
C
i
) and the integrity of MAC
k
(ID
C
i
,
T
S
i
, W
2
, M
6
,M
7
)
Server S
i
is authenticated
(6) Computes:
K
C
i
=r
C
i
. W
2
Sk = H
3
(ID
C
i
, T
C
i
, T
S
i
, W
1
, W
2
, K
C
i
)
M
8
=M
6
M
1
=r
S
i
M
9
= H
4
(M
6
||M
8
)
(4) C
2
=Enc{ID
C
i
, T
S
i
,W
2
, M
6
,
M
7
, MAC
k
(ID
C
i
, T
S
i
, W
2
, M
6
,
M
7
)}
a
(7) C
3
= Enc{M
9
, MAC
k
(M
9
)}
a
(1) Decrypts C
1
, then checks validity of ID
c
i
and freshness of T
c
i
(2) Computes:
M
2
=(x+H
1
(ID
C
i
))
-1
.W
1
k=H
2
(ID
C
i
, T
C
i
, W
1
, M
2
)
Checks the integrity of MAC
k
(ID
C
i
,
T
C
i
,W
1
, M
3
)
(3) Computes:
M
4
=H
4
(ID
C
i
||y)
W
2
=r
S
i
.P
K
S
i
=r
S
i
.W
1
Sk=H
3
(ID
C
i
, T
C
i
, T
S
i
W
1
, W
2
, K
S
i
)
M
5
=M
3
M
4 =
r
C
i
M
6
=M
4
r
S
i
M
7
= H
4
(M
3
||M
5
)
(8) Decrypts C
3
and verifies M
9
?=
H
4
(M
6
r
S
i
)
Client C
i
is authenticated
Figure 1. The new proposed protocol

TABLE 2. NOTATIONS USED IN THE NEW PROTOCOL
Definition
User/Client /Computer
Server
Registration Centre
Identity of Server
Identity of user C
User’s password
Biometric template of C
Public Key
Private Key
Message concatenation operation
A point on elliptic curve E with order n
Denotes point multiplication on elliptic curve
A piece of secret information maintained by the server
The server S’s Private/Public key pair, where
Pub_K
s
= xP
A random number chosen by the C
i
and S
i
respectively
A secure one-way hash function
The secure message authentication code of m under the
key k
XOR operation
We have examined and validated the behaviour of the
proposed protocol by using finite-state machines and Petri nets
[14]. The following steps explain the methodology to model
the proposed protocol with Petri nets:
1) Build a PN trust model of the trust relationship using
TAPAAL [15] simulation and verification software.
The following steps are necessary for the process of
modelling:
(a) Define the places and transitions and declare
their functionalities
(b) Implement a token passing scheme once the
initial marking is set
(c) Assess the model’s behaviour by examining
reachability, boundedness, and liveness
(d) Validate the model using simulation
2) Add the adversary model. This step involves the
following:
(a) Extend the original model and define places
and transitions for the adversary entities
(b) Implement the token-passing scheme with
the adversary
(c) Model different attack and identify any
insecure behaviour
III. CLIENT-SERVER TRUST MODELLED VIA PN
The trust model is a notation for determining whom the
organisations should trust with its assets. For example,
organisations usually verify the applicants’ resumes and
references, and conduct background and history checks before
trusting their employees. Once they are employed, they will be
issued photo ID badges and parking permits. In contrast to the
real world, it is challenging in the virtual world to identify
individuals who are trusted and those who are not. A trust
relationship between a client and a server can be obtained in
different practices. Some systems use the traditional way that
relies on passwords and digital certificates. Sometimes it may
involve a trusted third party to operate the authentication and
validation, such as the Kerberos login protocol [1], while other
systems deploy biometric automated verification systems to
recognise trusted users.
In the proposed trust model, the client-server trust
relationship is initiated during the registration phase. First, the
client submits his/her ID, password (PW
C
i
), and biometric data
(Bio
C
i
). Then the server will issue in return a corresponding
private key (Pr_K
C
i
), secret key (a) for the symmetric
encryption, and τ predetermined threshold for biometric
verification. The assumption for this model is that the client
and server are trustable entities, and they never cheat. Timed-
arc Petri Nets are used to model the new protocol. The trust
model consists of two Petri net entities: one for the client C
and the other for the server S. The protocol entities are derived
from the protocol description in [12]. The assumption made
for this model is that each legitimate participant is honest, i.e.
behaves according to the protocol rules. The Petri net model in
Fig. 2 represents the trust model for the proposed protocol.
The definitions of the places and transitions used in this model
are illustrated in Table 3 and Table 4, respectively.
Table 3. DEFINITIONS OF PLACES FOR THE TRUST MODEL
Place
Definition
Place
Definition
P
1
Client random number
P
14
Encrypted SYN/ACK
P
2
Client timestamp
P
15
Decrypted SYN/ACK
P
3
SYN request
P
16
Verification message
P
4
Login request
P
17
Rejected request
P
5
Encrypted login
request
P
18
Accept request Server
is authenticated
P
6
Decrypted login req.
P
19
Session key
P
7
Verification message
P
20
ACK
P
8
Rejected request
P
21
Encrypted ACK
P
9
Accepted request
P
22
Decrypted ACK
P
10
Server random number
P
23
Verification message
P
11
Server timestamp
P
24
Rejected request
P
12
Session Key
P
25
Accept request Client
P
13
SYN/ACK
is authenticated
Table 4. DEFINITIONS OF TRANSITIONS FOR TRUST MODEL
Trans.
Definition
Trans.
Definition
T
1
Compute login request +
SYN
T
10
Split the packet and
verify
T
2
Encrypt
T
11
Drop the packet
T
3
Decrypt
T
12
Accept
T
4
Split the packet and verify
T
13
Compute ACK and
session key
T
5
Drop the request
T
14
Encrypt ACK
T
6
Accept
T
15
Decrypt ACK
T
7
Compute SYN/ACK and
session key
T
16
Split the packet and
verify
T
8
Encrypt SYN/ACK
T
17
Drop the packet
T
9
Decrypt SYN/ACK
T
18
Accept

In the trust model, the channels between C and S are
depicted by interconnected arcs, which are attached to places.
The exchange messages procedure is represented by tokens.
Places represent storage for requests, messages, ciphers, or
session keys. Transitions in the model describe particular
functions or procedures, which may be performed while in an
execution state. For example, the following events produce a
new state: encryption, decryption, verification, and
computations. Tokens are modelled in PN as shown in Fig. 2
to represent the key agreement and message exchange
between the client and server. During simulation, the token
firing rule imitates the three-way handshake procedure. The
structure of a place linked to a transition represents a segment
of serial processes performed by the entity to fulfil its role in
the protocol run. For instance, the transition T
1
in Fig. 2
consumes three tokens from P
1
, P
2
, and P
3
to calculate the
login request. The PN trust model represents a three-way
handshake producer between C and S. It allows both C and S
to agree on a shared session key over an insecure channel. The
steps of protocol analysis for PN trust model are described as
follows:
At first, the protocol is initiated by a client. The client
entity of the PN trust model generates a random value
(P
1
), Timestamp (P
2
), SYN request (P
3
) to compute the
login request (P
4
) within a certain period of time. C sends
the encrypted request (P
5
) to S.
Upon receiving the request, S will check the age of the
token. Note that, computing and sending the request to S
takes some units of time. S will drop the request if the
time processing exceeds the deadline. This is guaranteed
by the use of transport arcs that preserve the age of the
tokens and the corresponding invariants.
! In the second message of the handshake, the server entity
generates a random value (P
10
), timestamp (P
11
) to
compute the session key (P
12
), and SYN/ACK request
(P
13
). Then S sends the encrypted SYN/ACK (P
14
) to C.
Upon receiving SYN/ACK, C checks the token age and
computes the session key (P
19
). At this stage, C
authenticates S and sends an enciphered ACK (P
21
) to S.
Finally, the server entity checks the token age and
authenticates C.
IV. TRUST MODEL WITH ADVERSARY MODELLED VIA PN
The purpose of this analysis is to find weaknesses and flaws
in the proposed protocol. It is essential to examine the
behaviour of the protocol with the presence of a malicious
adversary. An adversary entity can be a hacker, a malicious
insider, a disgruntled employee, a terrorist, organised crime, or
competitors.
Client
Server
Figure 2. The client-server trust model

The worst-case scenario would be if attackers obtained
illegitimate access to the target system. They could install
malicious software, like a rootkit, to remove or modify data.
This act of unauthorised access could lead to privilege
escalation and allow the attacker to gain elevated entry to
resources that are meant to be protected from other application
users. Moreover, faulty protocols may allow an attacker to
compromise other machines in the network to act as zombie
computers to launch denial-of-service attacks.
PN modelling is capable of mapping out how messages
flow throughout the protocol with an adversary. A high-level
view of the adversary model with information flow is shown
in Fig. 3.
The adversary entity is composed of processes, each
designed for a specific function in the protocol. Each process
models the adversary’s possible actions to capture tokens. It
can intercept messages from the channel, alter them, and pass
them to the target source.
Conceptually, the adversary entity is nondeterministic, in
that it may perform different possible actions under different
client identities at a given time to ultimately compromise the
target system. The following assumptions are considered for
the adversary model:
1) The adversary can eavesdrop, intercept, and store
messages. It may block or pass any of these
messages. Additionally, it may construct forged
messages from captured data and inject them into the
channel.
2) The adversary has zero knowledge such that it does
not possess any elements of messages transmitted
between the legitimate nodes but it can learn by
observing the traffic.
3) The traffic between client and server is not encrypted.
The main goal of the adversary model is to examine the
protocol behaviour with the presence of an adversary while
modelling attacks. In the adversary model (attack model), the
description of client and server entities is similar to the trust
model descried in section 3. For adversary entity, places
represent an adversary database, which store, control,
knowledge and accumulate all the intercepted messages.
Transitions represent a set of input events and commands the
adversary may perform to launch an attack. The input token in
the adversary entity indicates that the message has been
captured. The token movement from place to place through
the directed arcs indicates the progress of an attack. To
distinguish a genuine traffic from forged traffic, the grave
symbol ` is used to indicate that the variable could be
modified. For example, if the adversary intercepts the message
[A, B, C], the output message would be [A`, B`, C`], which
means the message has been manipulated by the adversary.
A. Analysis of Man-in-the-Middle Attack
After adding an adversary entity to the model, it can be
noticed that there is the possibility of a man-in-the-middle
between the two entities C and S. An active adversary A can
intercept the communication line between a legitimate client
and a trusted server as well as manipulate the protocol by
using some means to successfully masquerade either as server
or client. The attack model in Fig. 4 represents the man-in-the-
middle attack for the proposed protocol. The definitions of the
places and transitions used in this model are illustrated in
Table 5 and Table 6, respectively.
Table 5. DEFINITIONS OF TRANSITIONS - MAN-IN-THE-
MIDDLE ATTACK MODEL
Trans.
Definition
Trans.
Definition
T
1
Compute login request
T
13
Send forge SYN/ACK
+ SYN
T
14
Receive forge SYN/ACK
T
2
Send MSG
T
15
Split the packet and verify
T
3
Intercept MSG
T
16
Drop the request
T
4
Duplicate MSG
T
17
Accept
T
5
Send forge MSG
T
18
Compute ACK and
T
6
Received Forge MSG
session key
T
7
Split the packet and
T
19
Send ACK
verify
T
20
Intercept MSG
T
8
Drop the request
T
21
Send forge ACK
T
9
Accept
T
22
Receive forge ACK
T
10
Compute SYN/ACK
T
23
Split the packet and verify
and session key
T
24
Drop the request
T
11
Send SYN/ACK
T
25
Accept
T
12
Intercept MSG
Server
Adversary
Client
Figure 3. High-level view of adversary entity attacking the protocol

References
More filters

Journal ArticleDOI
Tadao Murata1Institutions (1)
01 Apr 1989
TL;DR: The author proceeds with introductory modeling examples, behavioral and structural properties, three methods of analysis, subclasses of Petri nets and their analysis, and one section is devoted to marked graphs, the concurrent system model most amenable to analysis.
Abstract: Starts with a brief review of the history and the application areas considered in the literature. The author then proceeds with introductory modeling examples, behavioral and structural properties, three methods of analysis, subclasses of Petri nets and their analysis. In particular, one section is devoted to marked graphs, the concurrent system model most amenable to analysis. Introductory discussions on stochastic nets with their application to performance modeling, and on high-level nets with their application to logic programming, are provided. Also included are recent results on reachability criteria. Suggestions are provided for further reading on many subject areas of Petri nets. >

10,345 citations


"A New Biometric ID-Based Cryptograp..." refers background or methods in this paper

  • ...Generally Petri nets focus on specific properties such as liveness, deadlock, livelock, boundedness and safeness [9-11]....

    [...]

  • ...It is used as a visual communication aid to model concurrency, synchronisation, limited resources, sequentially, mutual exclusion and behaviour in distributed systems [9-11]....

    [...]

  • ...The formal definition of a Petri net is shown in Table 1 [10]....

    [...]

  • ...In other words, a Petri net must consist of the following components [9-11]:...

    [...]


Book ChapterDOI
Adi Shamir1Institutions (1)
23 Aug 1985
Abstract: In this paper we introduce a novel type of cryptographic scheme, which enables any pair of users to communicate securely and to verify each other’s signatures without exchanging private or public keys, without keeping key directories, and without using the services of a third party. The scheme assumes the existence of trusted key generation centers, whose sole purpose is to give each user a personalized smart card when he first joins the network. The information embedded in this card enables the user to sign and encrypt the messages he sends and to decrypt and verify the messages he receives in a totally independent way, regardless of the identity of the other party. Previously issued cards do not have to be updated when new users join the network, and the various centers do not have to coordinate their activities or even to keep a user list. The centers can be closed after all the cards are issued, and the network can continue to function in a completely decentralized way for an indefinite period.

6,530 citations


Book
01 Jan 1981

3,504 citations


01 Jan 1962
TL;DR: The theory of automata is shown not capable of representing the actual physical flow of information in the solution of a recursive problem and a theory of communication is proposed that yields a means of representation that with equal rigor and simplicity accomplishes more than the theory of synchronous automata.
Abstract: Diese Arbeit befasst sich mit den begrifflichen Grundlagen einer Theorie der Kommunikation. Die Aufgabe dieser Theorie soll es sein, moglichst viele Erscheinungen bei der Informationsubertragung und Informationswandlung in einheitlicher und exakter Weise zu beschreiben. The theory of automata is shown not capable of representing the actual physical flow of information in the solution of a recursive problem. The argument proceeds as follows: 1. We assume the following postulates: a) there exists an upper bound on the speed of signals; b) there exists an upper bound on the density with which information can be stored. 2. Automata of fixed, finite size can recognize, at best, only iteratively defined classes of input sequences. (See Kleene (11) and Copi, Elgot, and Wright (8).) 3. Recursively defined classes of input sequences that cannot be defined iteratively can be recognized only by automata of unbounded size. 4. In order for an automaton to solve a (soluble) recursive problem, the possibility must be granted that it can be extended unboundedly in whatever way might be required. 5. Automata (as actual hardware) formulated in accordance with automata theory will, after a finite number of extensions, conflict with at least one of the postulates named above. Suitable conceptual structures for an exact theory of communication are then discussed, and a theory of communication proposed. All of the really useful results of automata theory may be expressed by means of these new concepts. Moreover, the results retain their usefulness and the new nrocedure has definite advantages over the older ones. The proposed representation differs from each of the presently known theories concerning information on at least one of the following essential points: 1. The existence of a metric is assumed for either space nor time nor for other physical magnitudes. 2. Time is introduced as a strictly local relation between states. 3. The objects of the theory are discrete, and they are combined and produced only by means of strictly finite techniques. The following conclusions drawn from the results of this work may be cited as of some practical interest: 1. The tolerance requirements for the response characteristics of computer components can be substantially weakened if the computer is suitably structured. 2. It is possible to design computers structurally in such a way that they are asynchronous, all parts operating in parallel, and can be extended arbitrarily without interrupting their computation. 3. For complicated organizational processes of any given sort the theory yields a means of representation that with equal rigor and simplicity accomplishes more than the theory of synchronous automata.

2,473 citations


"A New Biometric ID-Based Cryptograp..." refers background in this paper

  • ...The concept of the Petri net [7] was introduced in 1962 by Carl Adam Petri [8]....

    [...]


Book
21 Dec 2000
TL;DR: This book provides a thorough and detailed understanding of one of the most effective approaches to the design and evaluation of security critical systems, describing the role of security protocols in distributed secure systems and the vulnerabilities to which they are prey.
Abstract: Security protocols are one of the most critical elements in enabling the secure communication and processing of information, ensuring its confidentiality, integrity, authenticity and availability. These protocols are vulnerable to a host of subtle attacks, so designing protocols to be impervious to such attacks has proved to be extremely challenging and error prone.This book provides a thorough and detailed understanding of one of the most effective approaches to the design and evaluation of security critical systems, describing the role of security protocols in distributed secure systems and the vulnerabilities to which they are prey.The authors introduce security protocols, the role they play and the cryptographic mechanisms they employ, and detail their role in security architectures, e-commerce, e-cash etc. Precise characterizations of key concepts in information security, such as confidentiality, authentication and integrity are introduced and a range of tools and techniques are described which will ensure that a protocol guarantees certain security services under appropriate assumptions.Modeling and Analysis of Security Protocols provides: An in-depth discussion of the nature and role of security protocols and their vulnerabilities. A rigorous framework in which security protocols and properties can be defined in detail. An understanding of the tools and techniques used to design and evaluate security protocols.

305 citations


"A New Biometric ID-Based Cryptograp..." refers background in this paper

  • ...Sometimes it may involve a trusted third party to operate the authentication and validation, such as the Kerberos login protocol [1], while other systems deploy biometric automated verification systems to recognise trusted users....

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  • ...Typically cryptographic protocols, also known as security protocols, tend to inhabit a complex environment by utilising various cryptographic mechanisms, such as symmetric and asymmetric encryption, hash functions, timestamps, and digital signature [1]....

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