A Methodology for
Evaluating Wireless
Network Security Protocols
David Rager
Kandaraj Piamrat
Outline
► Introduction
► Explanation
of Terms
► Evaluation Methodology
► Analysis of WEP, WPA, and RSN
► Graphical Results
► Conclusion
Introduction
► Difference
properties of wireless network
comparing to wired network
► Two lines of defense in wireless network
security
 Preventive approach
 Intrusion Detection and Response approach
► WEP
WPA
RSN
Explanation of Terms
► WEP
– Wired Equivalent Protocol
(attempt #1)
► WPA – Wi-Fi Protected Access (attempt #2)
► RSN – Robust Secure Network (attempt #3)
► EAP – Extensible Authentication Protocol
► TKIP – Temporal Key Integrity Protocol
► AES – Advanced Encryption Standard
Explanation of Terms (cont.)
► CCMP
– Counter mode with Cipher block
Chaining Message authentication code
Protocol
► ICV – Integrity Check Value
► MIC – Message Integrity Check
► RADIUS – Remote Authentication Dial in
User Service
► IV – Initialization Vector
Evaluation Methodology
► Authentication
Capability
► Encryption Strength
► Integrity Guarantees
► Prevention of Attacks
► Identity Protection
► Ease and Cost of Implementation
► Power Consumption
► Novel Ideas
Authentication capability
Consideration
Type of
authentication
Number of
authentication
servers
Use of new
authentication
mechanisms
Known MITM
attacks
0(bad)
Key with
challenge
response
1(fair)
Key with
challenge
response and
MAC address
2(good)
Credentials based
One
Three
(# faults
permitted) * 3
+1
None
-
Use of EAP
(802.11X)[tec
h-faq]
One or more
-
None
Encryption Strength
Consideration
0(bad)
1(fair)
2(good)
Key type
Static key
-
Dynamic key
Cipher key type
RC4
-
AES
Cipher key length
40 or 104 bit
encryption
128 bit encryption
128 bit encryption +
64 bit
authentication
Key lifetime
24-bit IV
-
48-bit IV
Time used to crack
Few hours
Few days
Centuries
Encrypted packet
needed to crack
Few millions
-
Few trillions
Can be recovered by
cryptanalysis
Yes
-
No
Key management
used
None
Static
EAP
Integrity Guarantees
Consideration
Integrity of
message header
Integrity of the
data
0(bad)
1(fair)
2(good)
None
Michael
CCM
CRC-32
Michael
CCM
Prevention of Attacks
Consideration
0(bad)
1(fair)
2(good)
Replay attack
prevention
None
-
IV sequence , Perpacket key
mixing
DoS cookie
No
-
Yes
Number of known
attacks prevented
None
Some of them
All of them
Minimizes damage
No
-
Yes
Identity Protection
Consideration
0(bad)
1(fair)
2(good)
Group identity
revealed to
Entire network
All parties
Specific parties
Specific identity
revealed to
Entire network
All parties
Specific parties
Ease and Cost of Implementation
Consideration
0(bad)
1(fair)
2(good)
Computation cost
High
Medium
Low
Incremental installation
No
-
Yes
Number of messages
exchanged
300
30
3
Number of actors
involved
Many actors
-
Few actors
Packet key
Mixing function
Concatenated
No need
Additional server
hardware
Yes
-
No
Additional network
infrastructure
Yes
-
No
Number of gates in
client device
High
-
Low
Lines of Code
High
-
Low
Power Consumption
Consideration
0(bad)
1(fair)
2(good)
Clients use low
power
No
-
Yes
Client can detect
attacks and
enter lowpower mode
No
-
Yes
Novel Ideas
Consideration
0(bad)
1(fair)
2(good)
Determines
physical
location
No
-
Yes
Analysis of WEP
Authentication capability
Consideration
0(bad)
1(fair)
2(good)
Type of
authentication
Key with
challenge
response
Key with
challenge
response and
MAC address
Credentials based
Number of
authentication
servers
One
Three
(# faults
permitted) * 3 + 1
Use of new
authentication
mechanisms
None
-
Use of EAP
(802.11X)[techfaq]
Known MITM
attacks
One or more
-
None
Encryption Strength
Consideration
0(bad)
1(fair)
2(good)
Key type
Static key
-
Dynamic key
Cipher key type
RC4
-
AES
Cipher key length
40 or 104 bit
encryption
128 bit encryption
128 bit encryption +
64 bit authentication
Key lifetime
24-bit IV
-
48-bit IV
Time used to crack
Few hours
Few days
Centuries
Encrypted packet
needed to crack
Few millions
-
Few trillions
Can be recovered by
cryptanalysis
Yes
-
No
Key management
used
None
Static
EAP
Integrity Guarantees
Consideration
0(bad)
1(fair)
2(good)
Integrity of
message header
None
Michael
CCM
Integrity of the
data
CRC-32
Michael
CCM
Prevention of Attacks
Consideration
0(bad)
1(fair)
2(good)
Replay attack
prevention
None
-
IV sequence , Perpacket key mixing
DoS cookie
No
-
Yes
Number of known
attacks prevented
None
Some of them
All of them
Identity Protection
Consideration
0(bad)
1(fair)
2(good)
Group identity
revealed to
Entire network
All parties
Specific parties
Specific identity
revealed to
Entire network
All parties
Specific parties
Ease and Cost of Implementation
Consideration
0(bad)
1(fair)
2(good)
Computation cost
High
Medium
Low
Incremental installation
No
-
Yes
Number of messages
exchanged
300
30
3
Number of actors
involved
Many actors
-
Few actors
Packet key
Mixing function
Concatenated
No need
Additional server
hardware
Yes
-
No
Additional network
infrastructure
Yes
-
No
Number of gates in
client device
High
-
Low
Lines of Code
High
-
Low
Power Consumption
Consideration
0(bad)
1(fair)
2(good)
Clients use low
power
No
-
Yes
Client can detect
attacks and enter
low-power mode
No
-
Yes
Novel Ideas
Consideration
0(bad)
1(fair)
2(good)
Determines
physical location
No
-
Yes
Scores of WEP
► Authentication
Capability (0/8)
► Encryption Strength (0/16)
► Integrity Guarantees (0/4)
► Prevention of Attacks (0/6)
► Identity Protection (4/4)
► Ease and Cost of Implementation (17/18)
► Power Consumption (2/4)
► Novel Ideas (0/2)
Total Score = 2.44/8 = 30.56 %
Analysis of WPA
Authentication capability
Consideration
0(bad)
1(fair)
2(good)
Type of
authentication
Key with
challenge
response
Key with
challenge
response and
MAC address
Credentials based
Number of
authentication
servers
One
Three
(# faults
permitted) * 3 + 1
Use of new
authentication
mechanisms
None
-
Use of EAP
(802.11X)[techfaq]
Known MITM
attacks
One or more
-
None
Encryption Strength
Consideration
0(bad)
1(fair)
2(good)
Key type
Static key
-
Dynamic key
Cipher key type
RC4
-
AES
Cipher key length
40 or 104 bit
encryption
128 bit encryption
128 bit encryption +
64 bit authentication
Key lifetime
24-bit IV
-
48-bit IV
Time used to crack
Few hours
Few days
Centuries
Encrypted packet
needed to crack
Few millions
-
Few trillions
Can be recovered by
cryptanalysis
Yes
-
No
Key management
used
None
Static
EAP
Integrity Guarantees
Consideration
0(bad)
1(fair)
2(good)
Integrity of
message header
None
Michael
CCM
Integrity of the
data
CRC-32
Michael
CCM
Prevention of Attacks
Consideration
0(bad)
1(fair)
2(good)
Replay attack
prevention
None
-
IV sequence , Perpacket key mixing
DoS cookie
No
-
Yes
Number of known
attacks prevented
None
Some of them
All of them
Identity Protection
Consideration
0(bad)
1(fair)
2(good)
Group identity
revealed to
Entire network
All parties
Specific parties
Specific identity
revealed to
Entire network
All parties
Specific parties
Ease and Cost of Implementation
Consideration
0(bad)
1(fair)
2(good)
Computation cost
High
Medium
Low
Incremental installation
No
-
Yes
Number of messages
exchanged
300
30
3
Number of actors
involved
Many actors
-
Few actors
Packet key
Mixing function
Concatenated
No need
Additional server
hardware
Yes
-
No
Additional network
infrastructure
Yes
-
No
Number of gates in
client device
High
-
Low
Lines of Code
High
-
Low
Power Consumption
Consideration
0(bad)
1(fair)
2(good)
Clients use low
power
No
-
Yes
Client can detect
attacks and enter
low-power mode
No
-
Yes
Novel Ideas
Consideration
0(bad)
1(fair)
2(good)
Determines
physical location
No
-
Yes
Scores of WPA
► Authentication
Capability (6/8)
► Encryption Strength (14/16)
► Integrity Guarantees (2/4)
► Prevention of Attacks (4/6)
► Identity Protection (0/4)
► Ease and Cost of Implementation (5/18)
► Power Consumption (1/4)
► Novel Ideas (0/2)
Total Score = 3.32/8 = 41.49 %
Analysis of RSN
Authentication capability
Consideration
Type of
authentication
0(bad)
1(fair)
Key with
Key with
challenge response challenge response
and MAC address
2(good)
Credentials based
Number of
authentication
servers
One
Three
(# faults
permitted) * 3 + 1
Use of new
authentication
mechanisms
None
-
Use of EAP
(802.11X)[techfaq]
Known MITM
attacks
One or more
-
None
Encryption Strength
Consideration
0(bad)
1(fair)
2(good)
Key type
Static key
-
Dynamic key
Cipher key type
RC4
-
AES
Cipher key length
40 or 104 bit
encryption
128 bit encryption
128 bit encryption +
64 bit authentication
Key lifetime
24-bit IV
-
48-bit IV
Time used to crack
Few hours
Few days
Centuries
Encrypted packet
needed to crack
Few millions
-
Few trillions
Can be recovered by
cryptanalysis
Yes
-
No
Key management
used
None
Static
EAP
Integrity Guarantees
Consideration
0(bad)
1(fair)
2(good)
Integrity of
message header
None
Michael
CCM
Integrity of the
data
CRC-32
Michael
CCM
Prevention of Attacks
Consideration
0(bad)
1(fair)
2(good)
Replay attack
prevention
None
-
IV sequence , Perpacket key mixing
DoS cookie
No
-
Yes
Number of known
attacks prevented
None
Some of them
All of them
Identity Protection
Consideration
0(bad)
1(fair)
2(good)
Group identity
revealed to
Entire network
All parties
Specific parties
Specific identity
revealed to
Entire network
All parties
Specific parties
Ease and Cost of Implementation
Consideration
0(bad)
1(fair)
2(good)
Computation cost
High
Medium
Low
Incremental installation
No
-
Yes
Number of messages
exchanged
300
30
3
Number of actors
involved
Many actors
-
Few actors
Packet key
Mixing function
Concatenated
No need
Additional server
hardware
Yes
-
No
Additional network
infrastructure
Yes
-
No
Number of gates in
client device
High
-
Low
Lines of Code
High
-
Low
Power Consumption
Consideration
0(bad)
1(fair)
2(good)
Clients use low
power
No
-
Yes
Client can detect
attacks and enter
low-power mode
No
-
Yes
Novel Ideas
Consideration
0(bad)
1(fair)
2(good)
Determines
physical location
No
-
Yes
Scores of RSN
► Authentication
Capability (6/8)
► Encryption Strength (15/16)
► Integrity Guarantees (4/4)
► Prevention of Attacks (4/6)
► Identity Protection (0/4)
► Ease and Cost of Implementation (4/18)
► Power Consumption (2/4)
► Novel Ideas (0/2)
Total Score = 4.08/8 = 50.95 %
Graphical Results
Comparison of categorical
performance
Comparison of Categorical Performance
% of Points
Performance Category
0%
20%
40%
60%
80%
100%
Authentication Capability
Encryption Strength
Integrity Guarantees
Prevention of Attacks
Identity Protection
Ease and Cost of Implementation
Power Consumption
Novel Ideas
WEP
WPA
RSN
Main contributors to each protocol’s
success
Main Contributors to Each Protocol's Success
Novel Ideas
Power Consumption
% of Points
Ease and Cost of
Implementation
Identity Protection
Prevention of Attacks
Integrity Guarantees
Encryption Strength
WEP
WPA
Protocol
RSN
Authentication Capability
Conclusion
► We
have defined specific metrics for
protocol evaluation.
► We evaluate different wireless security
protocol based on these metrics.
► Questions ?