Wireless broadband

Wireless Broadband is a fairly new technology that provides high-speed wireless internet and data network access over a wide area.

According to the 802.16-2004 standard, broadband means 'having instantaneous bandwidth greater than around 1 MHz and supporting data rates greater than about 1.5 Mbit/s. This means that Wireless Broadband features speeds roughly equivalent to wired broadbandaccess, such as that of ADSL or a cable modem.

Compare the UK's Best Wireless Broadband Deals

Wireless Sensor Network

A wireless sensor network (WSN) is a wireless network consisting of spatially distributed autonomous devices using sensors to cooperatively monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants, at different locations.The development of wireless sensor networks was originally motivated by military applications such as battlefield surveillance. However, wireless sensor networks are now used in many civilian application areas, including environment and habitat monitoring, healthcare
applications, home automation, and traffic control.

While the term wireless network may technically be used to refer to any type of computer network that is wireless,the term is most commonly used to refer to a telecommunications network whose interconnections between nodes is implemented without the use of wires, such as a computer network (which is a type of communications network). Wireless telecommunications networks are generally implemented with some type of remote information transmission system that uses electromagnetic waves,such as radio waves,for the carrier and this implementation usually takes place at the physical level or "layer" of the network.

Wireless Network

Characteristics of Mobile Network

First Generation(1G):starts from 1980

AMPS,NMT,TACS
Analog
Voice services

Second Generation(2G):starts from 1992
GSM,D-AMPS
Digital
Voice/Data services(low speed)

Third Generation(3G):starts from 2001
UMTS,cdma2000
Digital
Voice/Wideband multimedia services

Frequency Bands of GSM

GSM900

Uplink:800~915 MHZ
Downlink:925~960 MHZ

GSM1800

Uplink:1710~1785 MHZ
Downlink:1805~1880 MHZ

GSM1900(Used in America & Canada)

Uplink:1850~1910 MHZ
Downlink:1930~1990 MHZ

Working with the Windows Prefetcher

What is the Prefetcher? It is a very nifty component of Windows XP that can seemingly read your mind and will start loading your program seconds before you actually start it to boost the startup of the application.

Although the Prefetcher keeps track of the applications that you run, creates optimized copies of them, and stores them in a special cache on your computer, this special cache is simply a location on your hard disk that has no, or very few, file fragments and stores application setting files. The next time you start your program,Windows will load it out of the Prefetcher cache, which is what causes the application to start up quicker.

If you really want to investigate this matter further, take a look at the Prefetcher cache. It is located in the Windows directory inside the Prefetcher folder. You will notice that the cache does not have an exact copy of each application because the files are a fraction of the size of the actual application executable file. Rather, it just has fragments of applications that are used to boost the performance of the startup.
The Prefetcher constantly monitors what applications you are running, even during parts of the bootup. That information is then passed on to help the disk defragmenter optimize the boot files.

The Prefetcher is a very complex component. The majority of the settings can be changed by hacking the registry; however, due to a lack of documentation on these settings, changing them without any guidance would be very risky. Thankfully, a few tips have surfaced in the vast documentation buried at Microsoft’s site and revealed in Microsoft’s applications.

Do you know to disable the system boot screen?

So, are you enjoying the fun blue bars moving across your screen when your system starts up? Not? Are you finding that you can live without the daily reminder that you are running Windows XP? If so, then you might want to consider removing the boot screen. One added advantage to doing so: You will be getting a boost of performance in return.

Disabling the boot screen might only save you a fraction of a second off your boot time. But keep in mind, every fraction of a second counts.

This performance improvement works on a very simple principle. It takes time for the computer to do anything.Taking away some work that it has to do, such as loading the boot screen, will free time that it can spend loading your system files instead.

The process for disabling the system boot screen is similar to the process for modifying the default operating system in the boot file. If you do not have any other operating systems installed on your system, then you will have to create your own boot.ini file to place in your drive root (that is, the c:\ drive). I am going to show how to create a file first, and will then show how to modify the boot.ini file if you already have one in your drive root or have multiple operating systems installed.

Creating boot.ini file

This section will show you how to create a boot.ini file for your computer if you have just one operating system installed and you do not already have a boot.ini file in your drive root. To get started, let’s go over what the boot.ini file looks like.

The boot.ini file that disables the boot screen looks like the following:

[boot loader]
timeout=0
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]multi(0)disk(0)rdisk(0)partition(1)\WINDOWS=
"Microsoft Windows XP Professional" /fastdetect /noguiboot

The above boot.ini file is pretty standard except for the addition of the /noguiboot to the last line of the file. That is the parameter that tells Windows to start up without using the graphical user interface boot screen. To get started, open up a copy of Notepad, found in the Accessories menu of the All Programs entry, in the Start Menu and follow these
steps:

1. On the first line of the file, type in [boot loader].

2. On line 2 of the file, key in timeout=0 so Windows does not show the boot selection screen at all. You don’t want this anyways because you only have one operating system installed on your computer.

3. On line 3 of the file, type in defaultmulti(0)disk(0)rdisk(0)partition(1)\WINDOWS
so that Windows knows where to look on your hard drive to start the operating system.

4. On line 4, type in [operating systems].

5. On line 5, type in multi(0)disk(0)rdisk(0)partition(1)\WINDOWS=”Microsoft
Windows XP Professional” /fastdetect /noguiboot to start up Windows with the
/noguiboot parameter to disable the boot screen.

6. Click the File menu bar item and select Save As.

7. Type Boot.ini in the File name box and change the Save as type to All Files.

8. Then, change the Save in directory to your drive root, which is usually Local Disk (C:).

9. Click the Save button and you are now finished.

You can now close Notepad. The next time you reboot your computer, you will not see the boot screen.

Hacking Techniques

All about autorun ini files

Extending the functionality of Autorun.inf

There are also some extensions to the autorun.inf file you can use that will put shortcutson the right-click menu of CD's icon. For example, add this to your autorun.inf (below the icon= line):

shell\read\command=notepad.exe readme.txt
shell\read=Read M&e First

The CD icon right-click menu will have a new item, “Read Me First” (with E as a hotkey)that launches Notepad with the readme.txt from the CD loaded. The ampersand (&)character in the second line denotes the hotkey letter, which is underlined in the menu. So Rea&d Me First would make ‘D’ the hotkey, and the menu item would appear as “Read Me First”. If you use hot keys (you don’t have to), do ensure that the letter you wish to use isn’t already assigned to a standard Windows context menu choice, such as Copy, Properties and Rename. The first listed menu entry for any hotkey gets executed. As for the open command, you can give a path to the file you wish to open (note as for the‘open=’ and ‘icon=’ lines, no leading backslash is used):

shell\read\command=notepad.exe mydocs\readme.txt

You can add more than one such context menu shortcut by tweaking the ‘read’ verb:

shell\read1\command=notepad.exe readme.txt
shell\read1=Read M&e First
shell\read2\command=notepad.exe EULA.txt
shell\read2=Read My E&ULA

This adds “Read Me First” and “Read My EULA” items to the CD’s right-click context menu. Items are added in the order they are in the autorun.inf. For more use ‘read3’, ‘read4’ etc. You may be aware that as from version 4.x, Adobe Reader can also be run from CD. This means that you can provide the user with a way of opening the Browser's "Quick Start guide" which is provided in PDF format - without assuming the user has Acrobat installed.

shell\read1\command=notepad.exe readme.txt
shell\read1=Read M&e First
shell\readit2\command=acrobat\reader\acrord32.exe
portbrws\qsg.pdf
shell\readit2=Read Quick Start Guide (PDF)

Note: the shell\readit2\command line is typed all as one line with a space between the 2 paths.

Hacking Techniques