IEEE 802.11e-2005, IEEE Standard for Information technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: Amendment 8: Medium Access Control (MAC) Quality of Service Enhancements
What you always wanted to know about networking but were afraid to ask!
* How the Internet works
* How e-mail, e-learning, and telephony work on the Internet
* What makes a network safe
* How traffic gets from here to there
* Disaster recovery and other ways to keep a network running
* How businesses share data
* See the world of Cisco networking with this illustrated guide s visual approach to learning
* Useful for both novices and networking professionals
* Covers a broad variety of internetworking topics-from e-mail to VPNs
At last-an illustrated guide to the world of Cisco networking. Cisco Networking Simplified breaks down the complicated world of internetworking into easy-to-understand parts. Learn quickly and easily the fundamentals of a variety of topics, such as security, IP telephony, and quality of service, from the full-color diagrams and clear explanations found in Cisco Networking Simplified.
Mobile communication devices like smart phones or tablet PCs enable us to
consume information at every location and at every time. The rapid development
of new applications and new services and the demand to access data in real time
create an increasing throughput demand. The data have to be transmitted reliably
to ensure the desired quality of service. Furthermore, an improved utilization of
the bandwidth is desired to reduce the cost of transmission.
With the rapid growth in the number of wireless applications, services and devices,
using a single wireless technology such as a second generation (2G) and third gener-
ation (3G) wireless system would not be efficient to deliver high speed data rate and
Quality-of-Service (QoS) support to mobile users in a seamless way. The next genera-
tion wireless systems (also sometimes referred to as Fourth generation (4G) systems)
are being devised with the vision of heterogeneity in which a mobile user/device will
be able to connect to multiple wireless networks (e.g., WLAN, cellular, WMAN)
simultaneously.
This book addresses two aspects of network operation quality; namely, resource
management and fault management.
Network operation quality is among the functions to be fulfilled in order to offer
quality of service, QoS, to the end user. It is characterized by four parameters:
– packet loss;
– delay;
– jitter, or the variation of delay over time;
– availability.
Resource management employs mechanisms that enable the first three parameters
to be guaranteed or optimized. Fault management aims to ensure continuity of service.
Quality of Service ( QoS ) has always been in a world of its own, but as the technology
has been refi ned and has evolved in recent years, QOS usage has increased to the point
where it is now considered a necessary part of network design and operation. As with
most technologies, large - scale deployments have led to the technology becoming more
mature, and QOS is no exception.
It was only a few years ago that “ubiquitous connectivity” was recognized as the future of
wireless communication systems. In the era of ubiquitous connectivity, it was expected that
the broadband mobile Internet experience would be pervasive, and seamless connectivity on
a global scale would be no surprise at all. The quality of service would be guaranteed no
matter when/where/what the users wanted with the connectivity. Connectivity would even be
extended to object-to-object communication, where no human intervention was required. All
objects would become capable of autonomous communication.
Driven by the desire to boost the quality of service of wireless systems closer to that afforded
by wireline systems, space-time processing for multiple-input multiple-output (MIMO)
wireless communications research has drawn remarkable interest in recent years. Excit-
ing theoretical advances, complemented by rapid transition of research results to industry
products and services, have created a vibrant and growing area that is already established
by all counts. This offers a good opportunity to reflect on key developments in the area
during the past decade and also outline emerging trends.
