The expansion and popularity of the Internet, along with the addition of wireless data functionality to wireless networks, has also contributed greatly to the growth of the wireless industry. In fact, the anticipated consumer demand for high bandwidth wireless data is commonly seen as the driving force behind current network upgrades and expansions. The number and types of companies aggressively investing in wireless technologies illustrate the importance of wireless data.
Wireless Sensor Networks (WSNs) can be defined as a self-configured and infrastructure-less wireless networks to monitor physical or environmental conditions, such as
temperature, sound, vibration, pressure, motion or pollutants and to cooperatively pass
their data through the network to a main location or sink where the data can be observed
and analysed. A sink or base station acts likean interface between users and the network.
One can retrieve required information from the network by injecting queries and gathering
results from the sink.
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Adaptive Cross-Layer Distributed Energy-Efﬁcient Resource Allocation Algorithms for Wireless Data Networks
This module introduces the Wireless LAN (WLAN) industry.
It is designed to give the student a brief overview of the history of WLAN products and the
evolution of those products, as well as to help the learner understand the development history
of Cisco Aironet® wireless product set.
It includes the following topics:
Wireless Data Networks
Cisco Wireless Advantages
Wireless sensor nodes are small, embedded computing devices that interface with sensors/
actuators and communicate using short-range wireless transmitters. Such nodes act
autonomously, but cooperatively to form a logical network, in which data packets are routed
hop-by-hop towards management nodes, typically called sinks or base stations. A Wireless
Sensor Network (WSN) comprises of a potentially large set of nodes that may be distributed
over a wide geographical area, indoor or outdoor
Nortel is a recognized leader in delivering communications capabilities that enhance the human experience, ignite and power global commerce, and secure and protect the world’s most critical information. Serving both service provider and enterprise customers, Nortel delivers innovative technology solutions encompassing end-to-end broadband, Voice over IP, multimedia services and applications, and wireless broadband designed to help people solve the world’s greatest challenges.
Over the past few years, many fundamental changes have taken place in wireless communications that will influence the future of this dynamic field. One phenomenon driving these changes has been the integration of wireless communicationdevices in people’s lives. While the 1990s were the years when wireless voice telephony became popular, the 2000s should be the time when wireless data applications are truly un-tethered from homes and offices.
I would like to dedicate this work to three very special people who have had a
profound impact in my life and in the creation of this work.
To Dana Axinger, whose quest for knowledge was the greatest driving factor
towards the development of this work.
Physical Layer. In this chapter, you will learn to:
Explain the role of Physical layer protocols and services in supporting communication across data networks.
Describe the purpose of Physical layer signaling and encoding as they are used in networks.
Describe the role of signals used to represent bits as a frame is transported across the local media.
Identify the basic characteristics of copper, fiber, and wireless network media.
Mobile and Wireless Communications have been one of the major revolutions of the late
twentieth century. We are witnessing a very fast growth in these technologies where mobile
and wireless communications have become so ubiquitous in our society and indispensable
for our daily lives. The relentless demand for higher data rates with better quality of services
to comply with state-of-the art applications has revolutionized the wireless communication
field and led to the emergence of new technologies such as Bluetooth, WiFi, Wimax, Ultra
In data networking, transmit means to issue signals to the network medium
Transmission refers to either the process of transmitting or the progress of signals after they have been transmitted
Since the fi nal decades of the twentieth century, data networks have known steadily growing
success. After the installation of fi xed Internet networks in many places all over the planet
and their now large expansion, the need is now becoming more important for wireless access.
There is no doubt that by the end of the fi rst decade of the twentieth century, high-speed wireless
data access, i.e. in Mb/s, will be largely deployed worldwide.
Tuyển tập các báo cáo nghiên cứu khoa học ngành toán học được đăng trên tạp chí toán học quốc tế đề tài: A virtual infrastructure based on honeycomb tessellation for data dissemination in multi-sink mobile wireless sensor networks
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: A virtual infrastructure based on honeycomb tessellation for data dissemination in multi-sink mobile wireless sensor networks
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài:
Research Article Adaptive Power Allocation in Wireless Sensor Networks with Spatially Correlated Data and Analog Modulation: Perfect and Imperfect CSI
Muhammad Hafeez Chaudhary and Luc Vandendorpe
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Combined Rate and Power Allocation with Link Scheduling in Wireless Data Packet Relay Networks with Fading Channels
Radio based communication, open air
The attacker, having a radio transmitter and receiver with the same radio frequency of the underlying wireless network, can easily:
Intercept wireless data
Connect his computing devices to a nearby wireless network
Inject new packets to an existing wireless network
Jam a particular wireless channel using a jamming device
Implement encryption algorithms, authentication algorithms, and integrity-check algorithms at the data-link layer
Provide network access with wired equivalent privacy
Higher-layer protocols and applications can be used ...