Wireless Networking: Encryption Algorithms, Strengths and Weaknesses

This article discusses the various encryption algorithms used in wireless networking, including DES, AES, RC4, SHA, MD5, PKI, PGP, Blowfish, WEP, WPA, and WPA2. It covers the strengths and weaknesses of each algorithm and also includes a ranking of the algorithms based on their effectiveness.

Running Head: WIRELESS NETWORKING 0
Student Name
[Type the
company name]
Wireless Networking

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Table of Contents
Part A.........................................................................................................................................1
Q1: DES (data encryption standard)......................................................................................1
Q2: Three DES.......................................................................................................................1
Q3: AES (Advanced Encryption Standard)...........................................................................3
Q4: RC4.................................................................................................................................3
Q5: SHA.................................................................................................................................4
Q6: MD5................................................................................................................................4
Q7: PKI (public key infrastructure).......................................................................................5
Q8: PGP (pretty good privacy)..............................................................................................6
Q9: Blowfish..........................................................................................................................6
Q10: Access control permission (ACP).................................................................................7
Q11: Symmetric encryption...................................................................................................7
Q12: Timestamps...................................................................................................................9
Q13: Access control permission (ACP)...............................................................................10
Q14: One message digits (MD5, SHA)................................................................................10
Q15: Replay security............................................................................................................11
Q16: WEP (Wired Equivalent Privacy)...............................................................................11
Q17: WPA...........................................................................................................................13
Q18: WPA2..........................................................................................................................13
Part 2: Ranking.........................................................................................................................13

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Part A
Q1: DES (data encryption standard)
It is a symmetric- key block cipher which is developed by NIST (National Institute of
standard and technology).
Strengths of DES: lies on two facts
1. 56-bit keys use: it is used in encryption. 256 possible keys make it impractical for a
brute force to attack on a number of keys like this.
2. The algorithm nature: by exploiting the DES algorithm’s characteristics, Cryptanalyst
is able to do cryptanalysis but none of them has succeeded to search weakness.
3. Able to recognize plaintext
Weakness: the design of the cipher has a weakness
1. Same output can be created because of 2 selected inputs to an S box
2. Starting and last permutation’s purpose is not clear.
3. It has a short key length which makes it easy to break
Q2: Three DES
Original DES was replaced by new triple DES which uses three keys including 56 bits
each.
Strength
 Works on 3 individual keys
 Able to make a dependable hardware encryption solution

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 Works on 168 bits
Weakness
 Slow
 Not strong enough to protect data for a longer time
 In limited resources platform, it is unsuitable.
Q3: AES (Advanced Encryption Standard)
It is an algorithm, trusted by various organizations as the standard. Commonly used
block cipher.
Strength
 Extremely efficient in the form of 128 bit.
 For heavy duty encryption, it uses 192 and 256 keys
 It is safe because it uses brute force 128 bit
Weakness
 The algebraic structure is too simple.
 With software, it is hard to implement
 It uses the same way of encryption for every block.
Q4: RC4
It is a shared key stream cipher algorithm which requires a secure exchange of shared
keys.it uses length keys from 1 to 256 bits. It is developed by Ronald Rivest.
Strength
1. Difficult to find any value in the table
2. The location used to select every value in a sequence is difficult to know

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3. The encryption is nearly 10 times faster than DES
Weakness
 It is considered as unsafe now
 In every 256 keys, one key is weak.
 A specific RC4 algorithm key can only be used once.
Q5: SHA
Belongs to the family of cryptographic functions which is designed to keep the data
safe. It transforms the data by using a hash function.
Strengths
 Designed with strong encryption to respond to hackers attack.
 Can be used to detect data tempering by hackers
 In case the database is hacked by the hacker, they will not find actual password but
only a hashed function.
Weakness
 Vulnerabilities have been exposed in SHA 1
 Slower than MD5, it requires 80 iterations
 The basic design of SHA 2 is quite similar to SHA1
Q6: MD5
It is a hashing algorithm with one way cryptographic function which accepts any length
and changes it to a fixed length value for authentication of the original message.
Strength

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 Faster, requires only 64 iterations
 The software implementation is simple, no large programs and long tables required
 It is almost impossible for a hacker to create two messages with same hash values
Weakness
 The propensity for collisions is a main weakness of MD5
 Attacks have been reported to some extent
 Not suitable for security-based applications
Q7: PKI (public key infrastructure)
Distribution and identification of public encryption keys have been supported by PKI.
It allows users to securely transfer data over the internet. It consists of software, hardware,
and policies.
Strength
 Able to verify the identity of an entity
 It is possible to protect personal information from hackers
 Strong data integrity
Weakness
 Slow
 The limited size of encrypted data
 Key may be shared with interested parties.

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Q8: PGP (pretty good privacy)
It is a popular program that is developed by Philip R. Zimmermann to encrypt and
decrypt electronic mail on the internet. It also used to authenticate messages by using digital
signatures.
Strength
 It combines IDEA and RSA it is possible to compensate the weakness of other
algorithms,
 It includes additional security for the user by preventing other users to decrypt the
data.
 It allows digital signature for security concerns.
Weakness
 The length of the cipher used in PGP is not easy to remember and must be recorded
 It has compatibility issues as it is necessary for sender and receiver to have
compatible versions of PGP
 PGP offers no forgot password option, so if the password is forgotten leads to loss of
messages.
Q9: Blowfish
It is an encryption algorithm which can be a replacement for other algorithms like
DES or IDEA. It uses same keys for both encryption and decryption. It is the symmetric
block cipher developed by Bruce Blowfish.
Strength
 Fast
 Compact and can work with very less memory (5k or less)

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 Secure
Weakness
 To encrypt nearly 4 kilobytes of text each key requires pre-processing equivalent,
which makes it slower than another available block cipher.
 As two users have the same key it cannot deliver authentication and non-repudiation
 Weak keys
Q10: Access control permission (ACP)
Access control permission is a strategy to enhance the security of network used in
private organizations. This protocol stops the availability of network to unauthorized devices.
Strength
 It provides freedom to an administrator to decide who can use the data and who
cannot.
 Can perform authentication, identification, and Authorization.
 Login credentials used in this protocol are PINs, biometric scans, and password.
Weakness
 Level of security can be set by a user
 The permission can be inherited by any programs
 Least restrictive
Q11: Symmetric encryption
It is the simplest encryption which includes an only single private key to cipher and
deciphers the information
Strength

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 Fast
 Only a system with secret key able to decrypt a message
 Stronger if the key is protected.
Weakness
 Vulnerable because the keys must be exchanged with two users.
 More data damage is possible if the key is compromised
 A digital signature that is difficult to repudiate cannot be provided
Asymmetric encryption
It is a public key cryptography method which uses two keys for encryption of a plain
text.
Strength
 Uses two keys to boost security
 Scalable
 It can provide a digital signature
Weakness
 Slower than symmetric encryption
 More complex than symmetric encryption
 It is possible to generate a pair of key
One-way encryption
It is also known as one way hash function. It can be difficult to reverse the encryption
and to find two strings with same hash value.

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Strength
 The digital signatures can be send
 Enough keys are required in order to attempt attack computationally
 The process cannot be reversed after hashing the password
Weakness
 Weaker algorithms
 Schema modification may be required
 Security vulnerabilities of data in transit
Q12: Timestamps
It is a computer recorded current time of an event. By using some mechanisms like
NTP (network time protocol), a computer manages to maintain the current time.
Strength
 Electronically signing documents
 Long-term validation of the signature
 For electronic signatures and codes, it provides extra security.
Weakness
 Within a reasonable time limit, a hacker can easily encode user's password by offline
password guessing.
 The wrong password cannot be detected earlier
 If the timestamps are not synchronized, there is a possibility of clock attack.

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Q13: Access control permission (ACP)
Access control permission is a strategy to enhance the security of network used in
private organizations. This protocol stops the availability of network to unauthorized devices.
Strength
 It provides freedom to an administrator to decide who can use the data and who
cannot.
 Can perform authentication, identification, and Authorization.
 Login credentials used in this protocol are PINs, biometric scans, and password.
Weakness
 Level of security can be set by the user
 The permission can be inherited by any programs
 Least restrictive
Q14: One message digits (MD5, SHA)
Message digits are also called the one-way hash function. The functions of message
digits distill the information within a file into one large number which is typically 128-256
bits long.
Strength
 SHA 2 algorithm with more than 128 bits is safe for security purpose.
 Unpredictability
 Strong collision resistance
Weakness
 The security of MD5 and MD2 algorithms has been compromised

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 SHA 0 reported to attacked by collision resistance attacks
 SHA 1 cannot be used where collision resistance property is needed
Q15: Replay security
The replay security or anti-replay protocols are a part of IETF and internet protocol
security. By using this protocol it is ensured that for an attacker it will not be possible to
make changes in message packets.
Strength
 Impossible to intercept message packets
 Against MITM attackers this method provides layer security
 It prevents duplicates by providing encryption
Weakness
 This protocol sometimes not works properly in some cases.
 There is a possibility to arise multiple valid packets with the same sequence
number.
 Sometimes good messages that take time to reach will be discarded.
Q16: WEP (Wired Equivalent Privacy)
It was developed for the wireless network and aimed to provide security level. In
1999 it was accepted as Wi-Fi security.
Strength
 The RC4 cipher used in this protocol is fairly strong
 It does not provide authentication, access control.
 There no replay prevention, message privacy, key protection

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Weakness
 Consists of 40-bit keys which makes it possible for brute force cracking
 The keys cannot be changed
 For management frames, it has no protection
WPA (Wi-Fi Protected Access)
It was an enhancement of WEP. For keys and generations of certificates, the
authentication server is used to in WPA.
Strength
 TKIP used in WPA consists a message integrity code in the text to make it sure that it
cannot be spoofed
 WEP has been wrapped in sophisticated cryptographic security techniques for data
privacy.
 Authentication by selecting an EAP type
Weakness
 TKIP used in this protocol uses same encryption like RC4 algorithm used in WEP.
 Design flows of WEP cannot be avoided in WPA
 For a DoS attack, WPA is susceptible
WPA2
It was an improved version of WPA, introduced in 2004.
Strength
 Uses advanced encryption standard for encryption.

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 AES is approved by US government.
 Good enough to protect home networks
Weakness
 By finding the WPS PIN it is possible to reveal WPA2 keys
 Some WPA and WPA2 interfere with each other when enables at the same time and
client connection failure can occur.
 The performance of network connections decreases by using WPA2 decreases.
Q17: WPA
Already discussed above in Question 16
Q18: WPA2
Already discussed above in Question 16
Part 2: Ranking
1. Triple DES
2. DES
3. Blowfish
4. AES
5. PKI
6. GPG/PGP
7. RC4
8. WPA2,WPA, WEP,
9. Timestamps
10. Symmetric encryption, asymmetric encryption and one-way encryption

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11. Access control permissions
12. Replay security
13. One-way message digests
14. SHA 1
15. MD5
Top 5 encryptions are found to be strong enough to use for IT Works on the basis of
key length used and efficient security ability against the hackers attacks.