Wiretapping, wireless jamming

1. Wiretapping, wireless
jamming
By Tsedey Shewakena
Id DBUE/809/11

2. Wiretapping
• is a technique of observing and analyzing the flow of data in a network in an active or
passive mode. The attack can perform denial of service attack by executing wiretapping.
• Wiretapping is the surreptitious electronic monitoring of telephone, telegraph, cellular, fax
or Internet-based communications.
• Wiretapping is achieved either through the placement of a monitoring device informally
known as a bug on the wire in question or through built in mechanisms in other
communication technologies. Enforcement officials may tap into either for live monitoring
or recording
• Commonly used modern day wiretapping tool. A variety of other tools, such as wiretap
Trojans, are used for different applications.

3. Types of wiretapping
There are 4 types of wiretap; such as
• Hardwired wiretap-a set of wires attached to an ‘isolation’ or ‘slave’ device is
attached to an existing wire that a signal travels on .The signal can then be
intercepted or bridged bank to a secure location.
• Soft wiretap-this requires a modification to the phone system software through the
telephone company a business PBX.
• Recording wiretap-this is quite simplistic and is simply a tape recorder hard wired
into the phone line and the tapes must be switched out regularity.
• Transmitting wiretap-this type of bug is an RF (radio frequency) transmitter typically
containing a mini microphone that is connected to a carrier current wire.

4. • For example, to secretly listen to people by connecting a listening device
to their telephone, or to attach a listening device to a telephone for this
purpose: The police chief was accused of illegally wiretapping
politicians, government officials, and journalists. We have laws to
protect us from people wiretapping our phones.

6. Wireless jamming
• Jamming is an effective way for the enemy to disrupt our command, control,
and communications on the battlefield. All the enemy needs to jam us is a
transmitter tuned to our frequency with enough power to override friendly
signals at our receivers. Jammers operate against receivers not transmitters.
• Wireless jamming aims at blocking wireless communication by keeping the
medium busy or by corrupting received signal using radio interference.

7. Attack strategies
• Scanning: Attack radio keeps hopping until it finds a channel that has legitimate
activity. It will stay until it detects lack of activity.
• Sweeping: Attackers periodically and simultaneously switch channels irrespective of
channel activity, and jam until the next period.

8. modesof jamming
Spot jamming
• Spot jamming is concentrated power directed toward one channel or
frequency.
Barrage jamming
• Barrage jamming is power spread over several frequencies or channels at the
same time. Jamming can be difficult, if not impossible to detect. For this reason,
we must always be aware of the possibility of jamming and be able to recognize
it.

9. Types of Jamming
• The two types of jamming most commonly encountered are obvious and subtle
jamming.
Obvious jamming. This is normally very simple to detect. The more commonly
used jamming signals of this type are described below. Do not try to memorize
them; just be aware that these and others exist. When experiencing a jamming
incident, it is more important to recognize and overcome the incident than to
identify it formally.

10. • Random noise -This is synthetic radio noise. It is random in amplitude and frequency.
It is similar to normal background noise and can be used to degrade all types of
signals. Operators often mistake it for receiver or atmospheric noise and fail to take
appropriate ECCM actions.
• Stepped tones -These are tones transmitted in increasing and decreasing pitch. They
resemble the sound of bagpipes. Stepped tones are normally used against single-
channel AM or FM voice circuits.
• Spark -The spark signal is easily produced and is one of the most effective for
jamming. Bursts are of short duration and high intensity. They are repeated at a rapid
rate. This signal is effective in disrupting all types of radio communications.
• Preamble jamming -This type of jamming occurs when a tone resembling the
synchronization preamble of the speech security equipment is broadcast over the
operating frequency of secure radio sets. Preamble jamming results in all radios being
locked in the receive mode. It is especially effective when employed against radio nets
using speech security devices.

11. • Gulls. The gull signal is generated by a quick rise and slow fall of a variable radio
frequency and is similar to the cry of a sea gull. It produces a nuisance effect
and is very effective against voice radio communications.
• Random pulse. In this type of interference, pulses of varying amplitude,
duration, and rate are generated and transmitted. They are used to disrupt
teletypewriter, radar, and all types of data transmission systems.
• Wobbler. The wobbler signal is a single frequency which is modulated by a low
and slowly varying tone. The result is a howling sound that causes a nuisance
effect on voice radio communications.
• Recorded sounds. Any audible sound, especially of a variable nature, can be
used to distract radio operators and disrupt communications. Music, screams,
applause, whistles, machinery noise, and laughter are examples.
Subtle jamming. Subtle jamming is not obvious; no sound is heard from our
receivers. They cannot receive an incoming friendly signal, even though
everything appears normal to the radio operator.

12. Techniques For Preventing Jamming
Attacks
• A. Steganography In Cryptography, It’s a practice of concealing messages or
information within another non-secret file, message, image, or video. it makes
the sender and receiver invisible. Thus, steganography provides not only
security but also anonymity.
• B. Cryptographic Puzzle Hiding Scheme In packet hiding scheme based on
cryptographic puzzles. Puzzles force the recipient of a puzzle to execute a pre-
defined set of computations before he is able to extract a secret of interest. The
time required for cracking the solution of a puzzle depends on its hardness and
the computational ability of the solver. It has higher computation and
communication overhead .

13. • C. All-Or-Nothing Transformation -The packets are pre-processed by an AONT
before transmission but remain unencrypted. The jammer cannot perform packet
classification until all pseudo-messages corresponding to the original packet have
been received and the inverse transformation has been applied.
• D. Triple DES - uses a key bundle which comprises 3 DES keys K1, K2, K3, each of
which 56 bits excluding parity bits. An Encryption algorithm is: Cipher text =
EK3(DK2(EK1(plaintext))) In encryption process, the plaintext is encrypted with K1,
decrypted with K2 and again encrypted with K3. Decryption algorithm is: Plaintext =
DK1(EK2(DK3(cipher text))). In decryption process, cipher text is decrypted with K3,
encrypted with K2, and again decrypted with K1. Each triple DES encryption encrypts
one block of 64 bits of data. In each case, the middle operation is reverse of first and
last .

14. REFERENCE
• http://www.spamlaws.com
• Neha Thakur , ArunaSankaralingam “Introduction to Jamming Attacks and Prevention
Techniques using Honeypots in Wireless Networks” in IRACST April 2013
• A. Charns , Cloak and Gavel; FBI Wiretaps, Bugs, Informers, and the Supreme Cour
Univ. of Illinois Press, 1992.
• http://www.ijlera.com

15. Thank you