Saturday, 27 August 2016
What is 802.11ac Wi-Fi, and how much faster than 802.11n is it?
Faster Wi-Fi: It’s something we all crave. Fortunately, it’s also something we can have, even on a budget. It’s not just about fast Internet speeds to and from your service provider. It’s also about transferring files between devices in your home or office, streaming video from a network-attached drive to a television, and gaming with the lowest network latencies possible. If you’re looking for faster Wi-Fi performance, you want 802.11ac — it’s that simple.
In essence, 802.11ac is a supercharged version of 802.11n. 802.11ac is dozens of times faster, and delivers speeds ranging from 433 Mbps (megabits per second) up to several gigabits per second. To achieve that kind of throughput, 802.11ac works exclusively in the 5GHz band, uses plenty of bandwidth (80 or 160MHz), operates in up to eight spatial streams (MIMO), and employs a kind of technology called beamforming that sends signal directly to client devices.
If you’re currently using an 802.11n router — or an even older 802.11b/g model, like the perennial favorite Linksys WRT54G — and are thinking of upgrading to 802.11ac, here’s what you need to know.
How 802.11ac works
Years ago, 802.11n introduced some exciting technologies that brought massive speed boosts over 802.11b and g. 802.11ac does something similar compared with 802.11n. For example, 802.11n supported four spatial streams (4×4 MIMO) and a channel width of 40MHz. But 802.11ac can utilize eight spatial streams and has channels up to 80MHz wide — which can then be combined to make 160MHz channels. Even if everything else remained the same (and it doesn’t), this means 802.11ac has 8x160MHz of spectral bandwidth to play with versus 4x40MHz — a huge difference that allows 802.11ac to squeeze vast amounts of data across the airwaves.
802.11ac also introduces standardized beamforming (802.11n had it, but it wasn’t standardized, which made interoperability an issue). Beamforming transmits radio signals in such a way that they’re directed at a specific device. This can increase overall throughput and make it more consistent, as well as reduce power consumption. Beamforming can be done with smart antennae that physically move to track a device, or by modulating the amplitude and phase of the signals so that they destructively interfere with each other, leaving just a narrow, interference-free beam. The older 802.11n uses this second method, which can be implemented by both routers and mobile devices.
Finally, 802.11ac, like 802.11 versions before it, is fully backwards compatible — so you can buy an 802.11ac router today, and it should work just fine with your older 802.11n and 802.11g Wi-Fi devices.
How fast is 802.11ac?
In theory, on the 5GHz band and using beamforming, 802.11ac should have the same or better range than 802.11n (without beamforming). The 5GHz band, thanks to less penetration power, doesn’t have quite the same range as 2.4GHz (802.11b/g). But that’s the trade-off we have to make: There simply isn’t enough spectral bandwidth in the massively overused 2.4GHz band to allow for 802.11ac’s gigabit-level speeds. As long as your router is well-positioned, or you have multiple routers, it shouldn’t matter much. The more important factors will be the transmission power and antenna quality of your devices.
And finally, the question everyone wants to know: Just how fast is Wi-Fi 802.11ac? As always, there are two answers: the theoretical max speed that can be achieved in the lab, and the practical maximum speed you’ll most likely receive at home in the real world, surrounded by lots of signal-attenuating obstacles.
The theoretical max speed of 802.11ac is eight 160MHz 256-QAM channels, each of which are capable of 866.7Mbps, for a total of 6,933Mbps, or just shy of 7Gbps. That’s a transfer rate of 900 megabytes per second — more than you can squeeze down a SATA 3 link. In the real world, thanks to channel contention, you probably won’t get more than two or three 160MHz channels, so the max speed comes down to somewhere between 1.7Gbps and 2.5Gbps. Compare this with 802.11n’s max theoretical speed, which is 600Mbps.
In situations where you don’t need the maximum performance and reliability of wired gigabit Ethernet — still a good option for situations requiring the highest performance — 802.11ac is certainly compelling. Instead of cluttering up your living room by running an Ethernet cable to the home theater PC under your TV, 802.11ac now has enough bandwidth to wirelessly stream the highest-definition content to your game console, set top box, or home theater PC. For all but the most demanding use cases, 802.11ac is a viable alternative to Ethernet.
The future of 802.11ac
802.11ac will only get faster, too. As we mentioned earlier, the theoretical max speed of 802.11ac is just shy of 7Gbps — and while you’ll never hit that in a real-world scenario, we wouldn’t be surprised to see link speeds of 2Gbps or more in the next few years. At 2Gbps, you’ll get a transfer rate of 256MB/sec, and suddenly Ethernet serves less and less purpose if that happens. To reach such speeds, chipset and device makers will need to implement four or more 802.11ac streams, both in terms of software and hardware.
We imagine Broadcom, Qualcomm, MediaTek, Marvell, and Intel are already well on their way to implementing four- and eight-stream 802.11ac solutions for integration in the latest routers, access points, and mobile devices — but until the 802.11ac spec is finalized, second-wave chipsets and devices are unlikely to emerge. Chipset and device manufacturers have plenty of work ahead to ensure advanced features, such as beamforming, comply with the standard and are inter-operable with other 802.11ac devices.
Tuesday, 23 August 2016
Windows keyboard shortcuts overview
Use shortcut keys as an alternative to the mouse when working in Windows. You can open, close, and navigate the Start menu, desktop, menus, dialog boxes, and Web pages using keyboard shortcuts. Keyboard shortcuts may also make it easier for you to interact with your computer.
Click a heading, or press TAB to highlight a heading, and then press ENTER.
General keyboard shortcuts
| Press | To |
CTRL+C
|
Copy.
|
CTRL+X
|
Cut.
|
CTRL+V
|
Paste.
|
CTRL+Z
|
Undo.
|
DELETE
|
Delete.
|
SHIFT+DELETE
|
Delete selected item permanently without placing the item in the Recycle Bin.
|
CTRL while dragging an item
|
Copy selected item.
|
CTRL+SHIFT while dragging an item
|
Create shortcut to selected item.
|
F2
|
Rename selected item.
|
CTRL+RIGHT ARROW
|
Move the insertion point to the beginning of the next word.
|
CTRL+LEFT ARROW
|
Move the insertion point to the beginning of the previous word.
|
CTRL+DOWN ARROW
|
Move the insertion point to the beginning of the next paragraph.
|
CTRL+UP ARROW
|
Move the insertion point to the beginning of the previous paragraph.
|
CTRL+SHIFT with any of the arrow keys
|
Highlight a block of text.
|
SHIFT with any of the arrow keys
|
Select more than one item in a window or on the desktop, or select text within a document.
|
CTRL+A
|
Select all.
|
F3
|
Search for a file or folder.
|
ALT+ENTER
|
View properties for the selected item.
|
ALT+F4
|
Close the active item, or quit the active program.
|
ALT+Enter
|
Displays the properties of the selected object.
|
ALT+SPACEBAR
|
Opens the shortcut menu for the active window.
|
CTRL+F4
|
Close the active document in programs that allow you to have multiple documents open simultaneously.
|
ALT+TAB
|
Switch between open items.
|
ALT+ESC
|
Cycle through items in the order they were opened.
|
F6
|
Cycle through screen elements in a window or on the desktop.
|
F4
|
Display the Address bar list in My Computer or Windows Explorer.
|
SHIFT+F10
|
Display the shortcut menu for the selected item.
|
ALT+SPACEBAR
|
Display the System menu for the active window.
|
CTRL+ESC
|
Display the Start menu.
|
ALT+Underlined letter in a menu name
|
Display the corresponding menu.
|
Underlined letter in a command name on an open menu
|
Carry out the corresponding command.
|
F10
|
Activate the menu bar in the active program.
|
RIGHT ARROW
|
Open the next menu to the right, or open a submenu.
|
LEFT ARROW
|
Open the next menu to the left, or close a submenu.
|
F5
|
Refresh the active window.
|
BACKSPACE
|
View the folder one level up in My Computer or Windows Explorer.
|
ESC
|
Cancel the current task.
|
SHIFT when you insert a CD into the CD-ROM drive
|
Prevent the CD from automatically playing.
|
Dialog box keyboard shortcuts
Press
|
To
|
CTRL+TAB
|
Move forward through tabs.
|
CTRL+SHIFT+TAB
|
Move backward through tabs.
|
TAB
|
Move forward through options.
|
SHIFT+TAB
|
Move backward through options.
|
ALT+Underlined letter
|
Carry out the corresponding command or select the corresponding option.
|
ENTER
|
Carry out the command for the active option or button.
|
SPACEBAR
|
Select or clear the check box if the active option is a check box.
|
Arrow keys
|
Select a button if the active option is a group of option buttons.
|
F1
|
Display Help.
|
F4
|
Display the items in the active list.
|
BACKSPACE
|
Open a folder one level up if a folder is selected in the Save As or Open dialog box.
|
Natural keyboard shortcuts
You can use the following keyboard shortcuts with a Microsoft Natural Keyboard or any other compatible keyboard that includes the Windows logo key () and the Application key (
).
) and the Application key ().
Press
|
To
|
|
Display or hide the Start menu.
|
| +BREAK |
Display the System Properties dialog box.
|
| +D |
Show the desktop.
|
| +M |
Minimize all windows.
|
| +Shift+M |
Restores minimized windows.
|
| +E |
Open My Computer.
|
| +F |
Search for a file or folder.
|
CTRL+
+F |
Search for computers.
|
| +F1 |
Display Windows Help.
|
| + L |
Lock your computer if you are connected to a network domain, or switch users if you are not connected to a network domain.
|
| +R |
Open the Run dialog box.
|
|
Display the shortcut menu for the selected item.
|
| +U |
Open Utility Manager.
|
Accessibility keyboard shortcuts
Press
|
To
|
Right SHIFT for eight seconds
|
Switch FilterKeys on and off.
|
Left ALT +left SHIFT +PRINT SCREEN
|
Switch High Contrast on and off.
|
Left ALT +left SHIFT +NUM LOCK
|
Switch MouseKeys on and off.
|
SHIFT five times
|
Switch StickyKeys on and off.
|
NUM LOCK for five seconds
|
Switch ToggleKeys on and off.
|
| +U |
Open Utility Manager.
|
Windows Explorer keyboard shortcuts
Press
|
To
|
END
|
Display the bottom of the active window.
|
HOME
|
Display the top of the active window.
|
NUM LOCK+ASTERISK on numeric keypad (*)
|
Display all subfolders under the selected folder.
|
NUM LOCK+PLUS SIGN on numeric keypad (+)
|
Display the contents of the selected folder.
|
NUM LOCK+MINUS SIGN on numeric keypad (-)
|
Collapse the selected folder.
|
LEFT ARROW
|
Collapse current selection if it's expanded, or select parent folder.
|
RIGHT ARROW
|
Display current selection if it's collapsed, or select first subfolder.
|
Note
| • |
You must associate a password with your user account to secure it from unauthorized access. If you do not have a password associated with your user account, pressing the
+L will not prevent other users from accessing your account information. |
| • |
Some keyboard shortcuts may not work if StickyKeys is turned on in Accessibility Options.
|
| • |
If you are connected to Windows through Microsoft Terminal Services Client, some shortcuts have changed. For more information, see the online documentation for Terminal Services Client.
|
You can add an Internet URL address bar to your Windows XP taskbar.
Doing so will let you type in URLs and launch Web pages without first launching
a browser. It will also let you launch some native Windows XP applications in
much the same way as you would via the Run menu (so you could type in calc to
launch the calculator or mspaint to launch Microsoft Paint. Here's how you add
the address bar:
1. Right-click on the taskbar, select Toolbars, and then click
Address.
2. The word Address will appear on your taskbar.
3. Double click it to access it.
4. If that doesn't work, your taskbar is locked. You can unlock it
by right-clicking on the taskbar again and uncheck Lock the Taskbar.
NOTE: You may also need to grab the vertical dotted lines beside
the word Address and drag it to the left to make the Address window appear.
BY:MISBAKH
AHMED
Go to the Windows Update web
site.
In the left pane, under Other Options, select “Personalize Windows
Update”.
Under “Set Options for Windows Update”, select the checkbox for
“Display the Link to Windows Update Catalog under ‘See Also’”, then click “Save
Settings”.
Go back to the Windows Update web site.
In the left pane, under “See Also”, select “Windows Update
Catalog”.
Select “Find Updates for Microsoft Operating Systems”.
Select the operating system and language of your choice.
Select “Critical Updates and Service Packs”.
Select all of
the patches you’d like to download, then click on “Go to download basket” to
download them.
BY:MISBAKH
AHMED
How To Make Your Own Radio Station
Must HAVE Winamp (Any Version)
First, things First your speed has to be at least 256/64 kbps
(which means Dial-up users, will have alot of latency, just dnt bother)
Second, your going to have to have a domain, an updated one with
the current i.p active. (Could be anything e.g. My sig)
Now, Your gonna have to download the Shoutcast Files.
Go to www.shoutcast.com to get the files.
Ok After downloading these, installing Both of them in any order i
dnt care. Go to START>PROGRAM FILES>SHOUTcast DNAS>EDIT SHOUTCAST DNS
CONFIG.
Ok your gonna have to Configure it:
Go Down and where it says password: change (that means your gonna
have to change it to whatever, make sure u remember)
The Portbase: change it to whatever port you want it
Maxusers: (lets be realistic here, dnt put in 10000, like NXS's
radio station) your bandwidth has to be extremely good, if your cable, 50 user
max is ok, ADSL should stay below 10 users, and T1 connections should do
whatever tickles there fantasy.
Open winamp, RIGHT CLICK>OPTIONS>PREFRENCES>DSP EFFECT>
and choose the NULLSOFT SHOUTCAST.
Go to OUTPUT, and then click on Connection, Through the ADDRESS,
type your address which you have done through www.no-ip.com, PORT NUMBER,
whatever u did in the EDIT.txt, and your password.
Then go to Encoder, and choose your quality of your music. Go back
to OUTPU>OUTPUT CONFIG> YELLOW PAGES. this is your advertisemant
information. dow hatever you like there.
Now Connect. to check that your Radio os on-line go to http://(your
address that you added in the prefrence)
BY:MISBAKH
AHMED
Tutorial : How to create a bootable Windows XP SP1 CD (Nero)
How to create a bootable Windows XP SP1 CD (Nero):
Step 1
Create 3 folders - C:\WINXPSP1, C:\SP1106 and C:\XPBOOT
Step 2
Copy the entire Windows XP CD into folder C:\WINXPSP1
Step 3
You will have to download the SP1 Update, which is 133MB.
Rename the Service Pack file to XP-SP1.EXE
Extract the Service Pack from the Run Dialog using the command:
C:\XP-SP1.EXE -U -X:C:\SP1106
Step 4
Open Start/Run... and type the command:
C:\SP1106\update\update.exe -s:C:\WINXPSP1
Click OK
Folder C:\WINXPSP1 contains: Windows XP SP1
How to Create a Windows XP SP1 CD Bootable
Step 1
Download xpboot.zip
http://thro.port5.com/xpboot.zip
( no download manager !! )
Extract xpboot.zip file (xpboot.bin) in to the folder C:\XPBOOT
Step 2
Start Nero - Burning Rom.
Select File > New... from the menu.
1.) Select CD-ROM (Boot)
2.) Select Image file from Source of boot image data
3.) Set Kind of emulation: to No Emulation
4.) Set Load segment of sectors (hex!): to 07C0
5.) Set Number of loaded sectors: to 4
6.) Press the Browse... button
Step 3
Select All Files (*.*) from File of type:
Locate boot.bin in the folder C:\XPBOOT
Step 4
Click ISO tab
Set File-/Directory length to ISO Level 1 (Max. of 11 = 8 + 3
chars)
Set Format to Mode 1
Set Character Set to ISO 9660
Check all Relax ISO Restrictions
Step 5
Click Label Tab
Select ISO9660 from the drop down box.
Enter the Volume Label as WB2PFRE_EN
Enter the System Identifier as WB2PFRE_EN
Enter the Volume Set as WB2PFRE_EN
Enter the Publisher as MICROSOFT CORPORATION
Enter the Data Preparer as MICROSOFT CORPORATION
Enter the Application as WB2PFRE_EN
* For Windows XP Professional OEM substitute WB2PFRE_EN with
WXPOEM_EN
* For Windows XP Home OEM substitute WB2PFRE_EN with WXHOEM_EN
Step 6
Click Burn tab
Check Write
Check Finalize CD (No further writing possible!)
Set Write Method to Disk-At-Once
Press New button
Step 7
Locate the folder C:\WINXPSP1
Select everything in the folder and drag it to the ISO compilation
panel.
Click the Write CD Dialog button.
Press Write
You're done.
BY:MISBAKH
AHMED