Seminar Report
on
“End-to-End Encryption Techniques”
Submitted to the
Savitribai Phule Pune University
In partial fulfillment for the award of the Degree of
Bachelor of Engineering
In
Information Technology
By
Yash Jondhale
Under the guidance of
Piya Mam
Department of Information Technology
2022-2023
ACKNOWLEDGEMENT
I have taken efforts in this project. However, it would not have been
possible without the kind support and help of many individuals and
organizations. I would like to extend my sincere thanks to all of them.
I would like to express my gratitude towards my parents & all the
faculty members for their kind co-operation and encouragement which help
me in completion of this project.
My thanks and appreciations also go to my colleague in developing
the project and people who have willingly helped me out with their abilities.
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End-to-End Encryption Techniques
ABSTRACT
Due to increased government surveillance as well as data breaches,
end-to-end encryption has recently received an increasing attention as a way
to protect against such threats.
Encryption manages the security of the information over a specific
network. In the ongoing world there are numerous applications that assists
with moving data and information over various systems which consequently
urges the inclination to think about the security of our information. In the
course of the most recent decade these encryption strategies have
experienced some extreme assessments where the top long range
interpersonal communication organizations were addressed.
Therefore, it is imperative to know about the significance of the Endto-End encryption strategies and methods of their executions. Henceforth,
the report puts together the brief highlights of various End-to-End
Encryption techniques.
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End-to-End Encryption Techniques
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TABLE OF CONTENT
List of Figures :
Fig 5.1: Symmetric Encryption
Fig 5.2: Asymmetric Encryption
Fig 5.3: RSA Algorithm
Fig 5.4: Block Diagram of Twofish
Fig 5.5: HMAC-SHA1 Generation
1. Introduction
2. Literature Survey
3. Problem Statement
4. Scope of Seminar
End-to-End Encryption Techniques
5. Methodology
5.1 Cryptography
5.2 Encryption
5.2.1 Types of Encryption
5.3 End-to-End Encryption
5.4 End-to-End Encryption Techniques
6. Applications
7. Conclusion
8. References
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End-to-End Encryption Techniques
CHAPTER 1
INTRODUCTION
Cryptography is a field of study and it is more broad in nature which
uses a digital signature to secure digital data. Encryption is an element of
cryptography. It is more of a mathematical process. It consists of only
encoding the message. Encryption of data is known for shielding
information from the snooping.
The encryption process transforms a given data into a pointless data
(called cipher text) with the help of some cryptographic algorithms. It helps
to facilitate secret messaging. It is utilized by algorithms like cipher to
encrypt digital data. This new message is totally different from the original
old message therefore, any hacker cannot read it so easily. It is usually done
using key algorithms.
Encryption can help to protect your non-shareable personal data like
passwords and pin numbers etc. It helps us to ensure that the data or message
has not been altered. The encryption process also safeguards us by protecting
our IP. It is a vital method which actively protects the data that you do not
want to be accessed by unauthorized party.
End-to-end encryption provides the gold-standard for protecting
communication. In an end-to-end encrypted system, the only people who can
access the data are the sender and the intended recipient(s) – and no one else.
Neither hackers nor unwanted third parties can access the encrypted data on
the server.
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End-to-End Encryption Techniques
CHAPTER 2
LITERATURE SURVEY
In the paper [1] written by Fabian Schillinger, Christian Schindelhaue, titled “End-toEnd
Encryption Schemes for Online Social Networks”, application of encryption techniques
to secure online social networks, different attacks caused because of lack of encryption
and their prevention are given.
In the paper [2] written by Oydin Ahmedova, Ulugbek Mardiyev, Otabek Tursunov, titled
“Generation and Distribution Secret Encryption Keys with Parameter”, the processes of
generating a public key and formicating a secret encryption key are performed in algebra
with a parameter.
In the paper [3] written by Maricel Grace Z. Fernando, Ariel M. Sison, Ruji P. Medina,
titled “Securing Private Key using New Transposition Cipher Technique”, algorithm that
protects the private key using the transposition cipher technique is explained.
In the paper [4] written by Kartik Giri, Namit Saxena, Yash Srivastava, Pranshu Saxena,
titled “End-to-End Encryption Techniques”, a detailed explanation of various end-to-end
encryption techniques is given. It includes algorithms like Triple DES, RSA with their
implementations using mathematical formulae for key generation and message encoding.
In the paper [5] published by WhatsApp, titled “WhatsApp Encryption Overview
Technical White Paper ”, a technical explanation of WhatsApp’s end-to-end encryption
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End-to-End Encryption Techniques
CHAPTER 3
system is given. It gives an overview of the “Signal Protocol” used by WhatsApp and its
use in WhatsApp. This end-to-end encryption protocol is designed to prevent third parties
and WhatsApp from having plaintext access to messages or calls.
In the paper [6] written by Sergej Dechand, Alena Naiakshina, Anastasia Danilova,
Matthew Smith, titled “In Encryption We Don’t Trust: The Effect of End-To-End
Encryption to the Masses on User Perception”, comparison of non end-to-end encrypted
communication like traditional SMS with end-to-end encrypted services like WhatsApp,
Signal, etc. is given.
PROBLEM STATEMENT
Improving privacy and securing conversation over the internet with
the help of end-toend encryption. Evaluating different end-to-end encryption
techniques for security and performance and choosing the most efficient and
secure algorithm.
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End-to-End Encryption Techniques
CHAPTER 4
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End-to-End Encryption Techniques
CHAPTER 5
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End-to-End Encryption Techniques
CHAPTER 4
SCOPE OF SEMINAR
Understanding the concept of encryption and decryption with the
various types. Study and compare different techniques used for encyrption
in end to end services. Evaluate the performance and security of modern
techniques like RSA, DES algorithms to help in deciding the best type of
encryption technique to use for a particular piece of information.
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End-to-End Encryption Techniques
CHAPTER 5
METHODOLOGY
5.1 Cryptography :
Cryptography is one of the traditional methods used to guarantee the privacy
of communication between parties. This method is the art of secret writing,
which is used to encrypt the plaintext with a key into ciphertext to be
transferred between parties on an insecure channel. Using a valid key, the
ciphertext can be decrypted to the original plaintext. Without the knowledge
of the key, nobody can retrieve the plaintext. Cryptography plays an
essential role in many factors required for secure communication across an
insecure channel, like confidentiality, privacy, nonrepudiation, key
exchange, and authentication.
5.2 Encryption :
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In cryptography, encryption is the process of encoding information. This
process converts the original representation of the information, known as
plaintext, into an alternative form known as ciphertext. Ideally, only
authorized parties can decipher a ciphertext back to plaintext and access the
original information.
5.2.1 Types of Encryption :
There are two types of encryption : symmetric and asymmetric encryption.
The name derives from whether or not the same key is used for encryption
and decryption.
1) Symmetric Encryption :
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End-to-End Encryption Techniques
The technique of Symmetric Encryption can also be known as the
symmetrickey, shared key, single-key, and eventually private-key
encryption. The technique of private key uses for all sides encryption
and decryption of secret data. The original information or plaintext is
encrypted with a key by the sender side also the similarly key is used
by the receiver to decrypt a message to obtain the plaintext. the key
will be known only by a people who are authorized to the
encryption/decryption. However, the technique affords the good
security for transmission but there is a difficulty with the distribution
of the key. If one stole or explore the key he can get whole data
without any difficulty. An example of Symmetric-Key is DES
Algorithm.
Fig 5.1: Symmetric Encryption
2) Asymmetric Encryption :
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End-to-End Encryption Techniques
We can call this technique as asymmetric cryptosystem or public key
cryptosystem, this technique use two keys which are mathematically
associated, use separately for encrypting and decrypting the
information. In this technique, when we use the private key, there are
no possibilities to obtain the data or simply discover the other key.
The key used for encryption is stored public therefore it’s called
public key, and the decryption key is stored secret and called private
key. An example of Asymmetric-Key Algorithm is RSA.
Fig 5.2: Asymmetric Encryption
5.1 End-to-End Encryption :
End-to-end encryption (E2EE) is a method of secure communication that
prevents third parties from accessing data while it's transferred from one end
system or device to another.
In end-to-end encryption, the data is encrypted on the sender's system or
device, and only the intended recipient can decrypt it. As it travels to its
destination, the message cannot be read or tampered with by an internet
service provider (ISP), application service provider, hacker or any other
entity or service.
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End-to-End Encryption Techniques
5.1.1 End-to-End Encryption Techniques :
A) Rivest Shamir Adleman Algorithm
Rivest, Adi Shamir and Leonard Adleman of MIT are the designers of the
RSA cryptographic algorithm in 1997. It was first portrayed in 1978. This
renowned security framework is made out of three stages, which are, Prime
Key generation, Encryption and Decryption.
The public key is used to encrypt the messages only and it is open and can
be used or seen to all. Therefore, it is not a secret key. The private key is
utilized to decrypt the messages. The private key is also called as secret key.
This method gives more effectiveness and unwavering quality over the
systems. Two techniques are used.
Firstly, the encryption strategy which is utilized to change over unique (plain
content) information to cipher text which is unreadable content. The plain
content is easily pursued by anybody.
Second procedure is decryption or unscrambling which is used to change
over cipher text content to plain text (intelligible format). Cipher content is
unreadable content i.e. opposite to plain text.
Fig 5.3: RSA Algorithm
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➢ Generate the RSA modulus (n) Select
two prime numbers, p and q.
Calculate n=p*q
➢ Find Derived Number (e)
Calculate the totient function: φ(n)=(p-1)(q-1)
Select an integer e such that e is co-prime to φ(n) and 1 < e < φ(n) .
➢ Form the public key (n,e)
The pair of numbers (n,e) makes up the public key.
➢ Generate the private key (n,d)
Determine d such that d*e=1 mod φ(n) and d <
φ(n) The pair of numbers (n,d) makes up the private
key.
➢ Encryption Formula
Given a plaintext p, represented as a number, the ciphertext c is calculated
as:
Encrypted Data (ciphertext) c = pe mod n
➢ Decryption Formula
Using the private key (n,d) , the plaintext can be found using:
Decrypted Data (plaintext) p = cd mod n
B) Triple DES
The Triple DES algorithm was required as an advancement for DES
algorithm because of advances in searching of key. The algorithm utilizes
three rounds of DES algorithm for encryption process which has a key length
of 168 bits i.e. (56*3). Either a few 56piece keys are used in the arrangement
for Encrypt-Decrypt-Encrypt (EDE).
First choice is to use three distinct keys for the encryption calculation to
create cipher message on plaintext message t.
C(t) = Ek1(Dk2(Ek3(t)))
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End-to-End Encryption Techniques
where C(t) is the figure content of plaintext message t, Ek1 is the encryption
technique utilizing key k1, Dk2 is the unscrambling or decryption strategy
using the key k2 and Ek3 represents the encryption strategy using key k3.
Another alternative is to use two distinct keys for the encryption calculation
which in turn uses low memory for keys in working of algorithm.
C(t) = Ek1(Dk2(Ek3(t)))
TDES with three keys requires 2168 potential mixes and that of two keys
requires 2112 potential mixes which is difficult for powerful attackers to
guess and is nearly impractical. This gives TDES as a most grounded
encryption algorithm which provides its application in banking industry. The
weakness of this calculation is that it is too tedious.
C) Two-fish Encryption Algorithm
Two-fish is a symmetric key algorithm which entails that encryption and
decryption can be done by using only one key. The block size of this
encryption algorithm is 128 bits and can take key of any length of up to 256
bits. It tends to be used in the applications where there is no RAM or ROM
accessible and where the keys are adaptable which implies the keys are
oftentimes changed.
It has a straightforward and adaptable plan with 128-bit Feistel network.
Twofish has something many refer to as “pre-brightening” and “postbrightening” in which extra subkeys are XORed into the content block both
before the first round and when last round is over.
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End-to-End Encryption Techniques
.
Fig5.4: Block Diagram of Twofish
The plain content experiences input brightening or pre-brightening before
the first round and afterward it experiences different phases of S-Boxes,
MDS lattices and PHT. After a few rounds, it experiences yield brightening
or post-brightening. After every one of these stages and a few adjusts, a
cipher text is produced. In brightening, both input and output information
are XORed with eight subkeys.
These XORed activities are called input brightening or pre-brightening and
yield brightening or post- brightening. In input brightening or prebrightening, the partitioned four bytes word is XORed with the 128-bit key
through key scheduler. The XORed blocks are currently passed in rounds.
In each round, the content block is broken into two halves.
The first half is sent over the F function and the other portion of content
block is XORed with it. In each round of Twofish, two expressions of 32 bit
each go about as a contribution to the F function. Each word is then divided
into four bytes and those words are sent to the four distinctive key reliant Sboxes.
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End-to-End Encryption Techniques
The four output bytes are joined with the help of a Maximum Distance
Separable (MDS) grid and consolidated into a 32-bit word. At this point the
two 32-bits words are unified by applying Pseudo-Hadamard Transform
(PHT), added to two round subkeys, at that point XORed with the other half
of the content.
Formulae for PHT:
a0 = a + b Mod 232
Key-reliant S-boxes are not chosen arbitrarily as they were get selected in
blowfish calculation. Rather, the Sboxes are deliberately structured and tried
with every single imaginable keys to affirm that all the developed S-boxes
are sufficient.
D) Keyed-Hashed Message Authentication Code (HMAC)
HMAC is a mix of hashing and cryptography. It uses secured hash functions
and secret key cryptography. It tends to check the information integrity and
realness of a message all the while. Any hashing calculation, for instance,
SHA-1, SHA-2, SHA-256 can be utilized to figure the HMAC. The quality
of the HMAC calculation relies upon the quality and size of hash function
and that of the key.
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End-to-End Encryption Techniques
Fig 5.5: HMAC-SHA1 Generation
This calculation uses two rounds to calculate the hash. The unknown key is
used to calculate the two keys called as inner key and outer key. In first
round, the inner key and message is used to process the inner hash. At that
point in second round, the inner hash and the external key is used to deliver
the HMAC code.
The HMAC can be defined as:
Where,
H is cryptographic hash function,
M is the message to be authenticated,
K is the secret key,
K’ is a block-sized key derived from the secret key,
|| denotes concatenation,
XOR is the bitwise exclusive OR, “opad”
is the block-sized outer padding,
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End-to-End Encryption Techniques
“ipad” is the block-sized inner padding.
Other than its capacity to check data integrity and message validation, one
motivation behind why it is enthusiastically prescribed is because of its
efficiency. Hash functions can take a message of unrestricted length and
converts it into a limited length digest. This signifies, regardless of whether
you have generally long messages, their relating message reviews can stay
short, subsequently permitting you to expand bandwidth.
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End-to-End Encryption Techniques
CHAPTER 6
APPLICATIONS
Over the past few years, the vulnerability of social networks like
Facebook or messaging apps like Chat has given rise to using end-to-end
encrypted platforms to protect communications. Today, platforms like
WhatsApp, Signal and PreVeil use endto-end encryption to protect the
exchanges of users’ data.
In this way end-to-end encryption is used to
• Secure online social media networking sites and applications.
• Secure sharing of sensitive documents and media.
• Protect users’ Privacy.
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End-to-End Encryption Techniques
CHAPTER 7
CONCLUSION
The report briefs the different techniques used for encryption in Endto-End services. Every encryption technique has its strong points and its
vulnerabilities. Where one technique may be lacking in availability, another
may be weak in distribution. Among all the techniques used in modern
world, the only way to really determine which one is superior is by
evaluating and comparing the various methods. Thus, for deciding which
encryption techniques to use, they have to decide what type of information
they want to secure.
To add up in the end, all the strategies examined above are helpful for
ongoing encryptions. Regular new encryption methods are advancing thus
quick and secure customary encryption procedures will consistently work
out with higher pace of security.
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End-to-End Encryption Techniques
CHAPTER 8
REFERENCES
[1] Schillinger F., Schindelhauer C. (2019) End-to-End Encryption Schemes for
Online Social Networks. In: Wang G., Feng J., Bhuiyan M., Lu R. (eds) Security,
Privacy, and Anonymity in Computation, Communication, and Storage. SpaCCS
2019. Lecture Notes in Computer Science, vol 11611.
Springer, Cham. https://doi.org/10.1007/978-3-030-24907-6_11
[2] O. Ahmedova, U. Mardiyev and O. Tursunov, "Generation and Distribution
Secret Encryption Keys with Parameter," 2020 International Conference on
Information Science and Communications Technologies (ICISCT), 2020, pp. 14,
doi: 10.1109/ICISCT50599.2020.9351446.
[3] M. G. Z. Fernando, A. M. Sison and R. P. Medina, "Securing Private Key using
New Transposition Cipher Technique," 2019 IEEE Eurasia Conference on IOT,
Communication and Engineering (ECICE), 2019, pp. 490-493, doi:
10.1109/ECICE47484.2019.8942798.
[4] Kartik Giri, Namit Saxena, Yash Srivastava, Pranshu Saxena, “End-to-End
Encryption Techniques”, IRJET Volume 7 - Issue 6 - June 2020
[5] WhatsApp, “WhatsApp Encryption Overview Technical white paper”, Version 3
Updated October 22, 2020
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End-to-End Encryption Techniques
CHAPTER 9
[6] S. Dechand, A. Naiakshina, A. Danilova and M. Smith, "In Encryption We Don’t
Trust: The Effect of End-to-End Encryption to the Masses on User Perception,"
2019 IEEE European Symposium on Security and Privacy (EuroS&P), 2019, pp.
401-415, doi: 10.1109/EuroSP.2019.00037.
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