Download A threat can be any person, object, or event that, if realized, could

Privacy In Wireless Networks
Priyanka Kadiyala
Introduction
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A network consists of 2
or more computers that
are linked in order to
share resources. They
may be linked through
cables, telephone lines
or radio waves.
Wired & Wireless
networks
Local Area Network
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The Institute of Electrical and Electronic
Engineers (IEEE) has defined a LAN as “a
datacomm system allowing a number of
independent devices to communicate directly
with each other, within a moderately sized
geographic area over a physical communications
channel of moderate rates”.
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Distributed File Storing, Remote Computing,
Messaging.
Security & Privacy Of A Network
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Security – Protection of networks and their services from
unauthorized modification, destruction, or disclosure.
Privacy – Protecting confidential details of a person or a
network.
Threats & vulnerabilities effect security of a network,
which in turn, implies that the privacy of the network
becomes insecure.
Privacy
Security
Threats
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A threat can be any person, object, or event that, if
realized, could potentially cause damage to the LAN.
Threats can be malicious, such as the intentional
modification of sensitive information, or can be
accidental, such as an error in a calculation, or the
accidental deletion of a file.
Vulnerabilities
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Vulnerabilities are weaknesses in a LAN that can be
exploited by a threat. For example, unauthorized
access (the threat) to the LAN could occur by an
outsider guessing an obvious password.
Reducing or eliminating the vulnerabilities of the
LAN can reduce or eliminate the risk of threats to the
LAN.
Security Concerns in a LAN
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Distributed File Storing – Inadequate protection
mechanisms on the local workstation. For example, a
personal computer (PC) may provide minimal or no
protection of the information stored on it. A user that copies
a file from the server to the local drive on the PC loses the
protection afforded the file when it was stored on the server.
Remote Computing - Concerns
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Remote computing must
be controlled so that
only authorized users
may access remote
components and remote
applications. The
inability to authenticate
can lead to unauthorized
users being granted
access to remote servers
and applications.
Topologies & Protocols - Concerns
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The topologies and protocols used today demand that
messages be made available to many nodes in reaching the
desired destination. This is much cheaper and easier to
maintain than providing a direct physical path from every
machine to every machine.
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Threats - active and passive wiretapping.
Passive wiretapping includes not only information
release but also traffic analysis.
Active wiretapping includes message stream
modifications (including modification, delay,
duplication, deletion or counterfeiting).
Other concerns
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Other LAN security problems include -inadequate
LAN management and security policies, lack of
training for proper LAN usage and security,
inadequate protection mechanisms in the workstation
environment, and inadequate protection during
transmission.
Inadequately protected email can easily be captured,
and perhaps altered and retransmitted, effecting both
the confidentiality and integrity of the message.
Wireless networks
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Wireless devices use Radio Frequency (RF) to facilitate
communication.
Various types of wireless communication solutions use
different frequencies, mostly regulated by governments.
802.11 and Bluetooth operate in the 2.4Ghz band.
Wide Area Networks (WANs) using GPRS, GSM, etc.
Local Area Networking (LANs) using 802.11b.
Personal Area Networking (PANs) using Bluetooth.
WLAN
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Medium range. Around 150-200ft.
Can be extended using directional antenna, repeaters,etc.
Benefits
–Removes need for cabling infrastructure.
–Rapid deployment.
How does it work?
–Clients ‘associate’ to ‘Access Points’ (AP’s) –
Infrastructure Mode.
–Clients form peer-to-peer network -‘Ad-Hoc’ Mode.
Bluetooth PAN
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Short range (around
10m or 30 feet).
Short range cable
replacement
technology, used to
transmit both voice and
data.
Gadget oriented.
IEEE 802.11 Standard
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Defines the physical layers and the MAC sublayers
for the wireless LANs.
Frequency Hopping Spread Spectrum Radio, Direct
Sequence Spread Spectrum Radio and Baseband
Infrared.
Data rate - 2 Mbps ; 2400 - 2483.5 MHz frequency
band.
Two authentication schemes: Open System
Authentication and Shared Key Authentication.
OSA–null authentication.
WEP Weaknesses
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Confidentiality: Prevent casual eavesdropping.
Access Control: Protect access to a wireless network
infrastructure.
Data Integrity: Prevent tampering with transmitted
messages.
WEP relies on the difficulty of discovering the secret
key through force.
Threats to Wireless Networks
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When transmissions are broadcast over radio waves,
interception and masquerading becomes trivial to
anyone with a radio, and so there is a need to employ
additional mechanisms to protect the communications.
Privacy & Security threats in wireless networks can be
Internal or external.
Internal – Rogue access points and Incorrectly
configured access points.
External – Eavesdropping, Identity theft, War driving,
Man-in-the-middle attacks,etc.
Eavesdropping
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Eavesdropping is very easy in the radio
environment, when one sends a message over the
radio path, anyone equipped with a suitable
transceiver in the range of the transmission can
eavesdrop the message. Undetectable.
Parking Lot Attack - Eavesdropping
Transitive Trust
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In wired networks we can always track the wire from
our computer to the next network node, but in the
wireless environment there is no such way to find out
with whom we are talking to. In all cases both parties
of the transmission should be able to authenticate each
others.
The only real protection against this kind of attacks is
the strong authentication mechanism of the mobiles
accessing the wireless LAN.
Man-In-The-Middle Attacks
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The attacker positions himself between the victim and the
device with which the victim is trying to communicate.
The attacker can impersonate the receiver with respect to
the sender, and the sender with respect to the receiver,
without having either of them realize that they have been
attacked.
An attacker can also impersonate a user. By monitoring
the frame transmissions, a hacker can program a rogue
radio NIC to mimic a valid one. In this way, the rogue
radio NIC steals the ongoing session for which the valid
user had logged into.
Identity Theft
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Service Set Identifiers (SSIDs), static WEP authentication
and Media Access Control (MAC) addresses are often used
to verify that clients are authorized to connect with an AP.
However, knowledgeable intruders can pick up approved
SSIDs and MAC addresses to connect to a WLAN as an
authorized user.
Internal Threats
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Rogue APs - Rogue WLANs can be attached to corporate
networks from authorized network users, inadvertently
opening doors for intruders.
Incorrectly configured APs: Radio waves broadcast by
wireless base stations are relatively powerful, and
residential neighbors or adjacent businesses may connect to
each other's wireless networks.
Many APs are initially configured to openly broadcast
SSIDs of authorized users. SSIDs can be incorrectly used as
passwords to verify authorised users, which allow intruders
to easily steal an SSID and assume the identity of an
authorized user.
Wardriving
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An unauthorized user
uses his mobile device
to access a network.
Incorrectly configured
APs may broadcast their
SSID so that any passer
by with the equipment
can associate and begin
sharing a network’s
Internet connection.
IEEE 802.11i Standard
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Addresses the
weaknesses of 802.11
data privacy by
incorporating
Temporal Key
Integrity Protocol
(TKIP), plus a
sophisticated keying
system that ties
together the data
privacy and
authentication
functions.
Possible Solutions
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Activate WEP at the very least - The use of standard
802.11 WEP for networks where there is low risk of
attack by actual hackers is a minimum for any security
policy.
Ensure only authorized people can reset the access
points. Some access points will revert back to factory
default settings (i.e., no security at all) when someone
pushes the reset button on the access point. This makes
the access point a fragile entry point for a hacker to
extend their reach into the network. As a result,
provide adequate physical security for the access point
hardware.
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Properly install all access points. Don't leave access
points within easy reach of a hacker who can replace a
legitimate safeguarded access point with an unsecured,
rogue access point that accepts access from any user.
Disable access points during non-usage periods.
Assign "strong" passwords to access points.
Reduce propagation of radio waves outside the facility.
Through the use of directional antennas, you can direct
the propagation of radio waves inside the facility and
reduce the "spillage" outside the perimeter. Reduces the
ability for someone to jam the WLAN from outside the
perimeter of the facility.
Questions
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Why does wireless need more security?
What are the impacts of such threats & vulnerabilities?
What is the solution?
References
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http://csrc.nist.gov/publications/fips/fips191/fip
s191.pdf
http://www.tml.tkk.fi/Opinnot/Tik110.501/1997/wireless_lan.html#Threats
http://www.pentest.co.uk/documents/wlesssalford.pdf
http://libproxy.library.unt.edu:2696/iel5/10753/
33896/01615051.pdf?tp=&arnumber=161505
1&isnumber=33896
Thank you