Transmission Interference

Most emerging radio technologies for Wireless Personal Area Networks such as the Bluetooth protocol are designed to operate in the 2.4 GHz ISM band. Since both Bluetooth and IEEE 802.11 devices use the same frequency band and may likely come together in a laptop or may be close together at a desktop, interference may lead to significant performance degradation. The main goal of this paper is to describe the interference problem and to highlight a coexistence framework for these technologies to operate in a proximal environment. It gives an overview of several coexistence solutions proposed for various interference scenarios. This paper presents several factors that may impact interference such as fragmentation and the choice of packet encapsulation and give simulation results for selected scenarios and configurations of interest. tech news

Our primary objective in the further development of wireless networks of any form today is to narrow, if not eliminate, the behavioral and performance differences that distinguishes wireless from wireline. So, while it is most certainly true that a wireless LAN is, in fact, a local-area network and therefore at least in theory capable of handling any mission suitable for a LAN, the "wireless" part of "wireless LAN" often gets in the way. The primary reasons for this are the vagaries of the radio channel, that property of the universe that allows data to move through the air in much the same fashion as it travels through wire. This White Paper will look at what can be done at the physical (radio) later to improve the performance of wireless-LAN systems. tech news

AirFlow's innovative single AP architecture accomplishes two tasks that once seemed mutually exclusive: solving the 802.11 Dilemma while still complying with the 802.11 standard. This innovative solution fundamentally eliminates the issues with RF interference and enables a breadth of benefits to network administrators and end-users alike. In the end, AirFlow has enabled a simple, scalable, and secure wireless network that is as easy to deploy as Ethernet. This white paper focuses on this solution. tech news

"This white paper presents a study of clock drift in computers and other networked devices. The paper starts with an introduction to clock architecture, distribution of standard time, drift in oscillators, and efforts to improve clock precision. This is followed by an equation for clock drift that shows the how the calculation for modeling drift in networks was established. Finally, statistical projections are presented along with results and conclusions about the significance of network clock error, even in relatively small networks. tech news

As we accelerate into the New World of VoIP we assume we can leave some of the trappings of wireline telecom behind, such as the need for synchronization. After all, an IP network is about as asynchronous as it gets. While this may be true in some respects, precise time and synchronization continue to permeate many areas of IP telephony operations. Customer expectations of voice quality and service reliability remain unchanged, and as a result, the need for precise time remains unchanged though it manifests itself in different ways. The bottom line is that trying to design a VoIP network without considering network synchronization is probably the shortest path to realizing that you need it. tech news