05-03-2013, 04:42 PM
Data Security In Wireless Networks
Data Security In Wireless Networks.pdf (Size: 45.99 KB / Downloads: 27)
ABSTRACT: -
Wireless Wide Area Networks (WAN) are a popular method of
wirelessly accessing data over the Internet. A major concern for many corporate users of
wireless WANs is data security and how to protect data that is transmitted over these
wireless networks.
There are many features of these wireless networks, which
provide user and data security. This paper discusses the security features for CDPD,
CDMA, and GPRS networks, as well as an introduction to virtual private networks
(VPN) and how these applications can be used to enhance the overall security of data
on wireless networks.
For each of the technologies presented in this paper, a brief
overview of the wireless network is given, followed by a discussion of each of the
features of that network that contribute to the overall security of the network.
INTRODUCTION: -
CDPD is a secure, proven, and reliable protocol that has been used
for several years by law enforcement, public safety, and mobile professionals
to securely access critical, private information. CDPD has several features to
enhance the security of the mobile end user’s data and these are discussed
below.
OPERATION OF CDPD: -
A brief overview of the operation of the CDPD network is as follows:
A wireless modem (or Mobile End System—M-ES) communicates by radio
with the Mobile Data Base Station (MDBS). The MDBS transfers this data by
landline and microwave to the Mobile Data Intermediate Systems (MD-IS),
which processes and sends the information, by Intermediate System gateways
(routers), to the appropriate destination.
CODE DIVISION MULTIPLE ACCESS (CDMA)
INTRODUCTION: -
CDMA is a recently patented technology but dates back to before
World War II, when inventors patented a way of sending signals over
different radio frequencies using random patterns to control torpedoes. The
idea was later used to secure communications for the U.S. government during
the Cuban Missile Crisis. The U.S. military declassified the technology in the
1980’s and it has now become CDMA cellular technology.
Spread-spectrum technology works by taking the conversations or
data and attaching a code (known only to the sender and receiver) to it. The
coded information is then split into packets and transmitted along with
multiple other conversations or data packets over the network. The receiver
then reassembles and decodes the data. This result in extremely secure
transmissions, because the coded information is spread over the same
bandwidth, resulting in trillions of possible combinations of coded messages.
Spread spectrum: -
CDMA is a “spread spectrum” technology, which means that the user
data is assigned a unique code and then “spread” over a greater bandwidth
than the original signal. The data bits of each call are then transmitted in
combination with the data bits of all the other calls in the cell. At the
receiving end, the digital codes are separated from the data, leaving only the
original information that was sent.
Spread spectrum technology was traditionally used in military
applications. It was secure enough for military applications, because the
signal is difficult to identify, jam, or interfere with, due to the wide bandwidth
of a spread spectrum signal. A spread spectrum signal is very hard to detect,
and appears as nothing more than a slight rise in the background noise.
Other technologies have the signal power concentrated in a narrower band
and are easier to detect.
ESN and MIN numbers: -
Each mobile device on a CDMA network has a unique Electronic
Serial Number (ESN) and Mobile Identification Number (MIN) associated
with it. The network is able to compare the ESN/MIN combination each time
a user connects to the network, and so increase security by not allowing
cloned or unauthorized devices onto the network.