Saturday, 17 May 2014

How to check if a computer that you are using has the 5 GHz network capability.

On the Command Prompt window, enter “netsh wlan show drivers” then press [Enter].
Step 3:
Look for the Radio types supported section.  If it says that the network adapter supports both  802.11a and  802.11n network modes, it means that the computer that you are using has the 5 GHz network capability.
In this example, the wireless adapter supports 802.11b, 802.11a, 802.11g, and 802.11n network modes.  This means that the computer has the 5 GHz network band capability.

On the Medion PC with a Linksys WUSB6300 Adaptor

C:\Users\Terry>netsh wlan show drivers

Interface name: Wireless Network Connection 3

    Driver                    : Linksys WUSB6300
    Vendor                    : Linksys LLC
    Provider                  : Linksys LLC
    Date                      : 14/06/2013
    Version                   : 1023.8.524.2013
    INF file                  : C:\Windows\INF\oem14.inf
    Files                     : 2 total
    Type                      : Native Wi-Fi Driver
    Radio types supported     : 802.11n 802.11n 802.11b 802.11g 802.11a
This supports 5GHz if the VirginMedia router is set to 5GHz


Interface name: Wireless Network Connection 2 This is the Edimax USB Wireless 802.11n Adapter

    Driver                    : 802.11n USB Wireless LAN Card
    Vendor                    : Ralink Technology, Corp.
    Provider                  : Ralink
    Date                      : 05/08/2009
    Version                   :
    INF file                  : C:\Windows\INF\oem13.inf
    Files                     : 4 total
    Type                      : Native Wi-Fi Driver
    Radio types supported     : 802.11b 802.11g 802.11n
This adaptor does not work on the VirginMedia router unless set to 2.4GHz setting

Question: What is Dual Band Wireless Networking?
Answer: In Wi-Fi wireless networking, dual band is the capability to transmit on the 5 GHz band of 802.11a and also the 2.4 GHz band used by 802.11b, 802.11g, and 802.11n. Unlike ordinary Wi-Fi equipment that only supports one signal band, dual-band gear contain two different types of wireless radios that can support connections on both 2.4 GHz and 5 GHz links.

Friday, 16 May 2014

Wireless Standards 802.11

There are several specifications in the 802.11 family:
  • 802.11 — applies to wireless LANs and provides 1 or 2 Mbps transmission in the 2.4 GHz band using either frequency hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS).
  • 802.11a — an extension to 802.11 that applies to wireless LANs and provides up to 54-Mbps in the 5GHz band. 802.11a uses an orthogonal frequency division multiplexing encoding scheme rather than FHSS or DSSS.
  • 802.11b (also referred to as 802.11 High Rate or Wi-Fi) — an extension to 802.11 that applies to wireless LANS and provides 11 Mbps transmission (with a fallback to 5.5, 2 and 1-Mbps) in the 2.4 GHz band. 802.11b uses only DSSS. 802.11b was a 1999 ratification to the original 802.11 standard, allowing wireless functionality comparable to Ethernet.
  • 802.11e — a wireless draft standard that defines the Quality of Service (QoS) support for LANs, and is an enhancement to the 802.11a and 802.11b wireless LAN (WLAN) specifications. 802.11e adds QoS features and multimedia support to the existing IEEE 802.11b and IEEE 802.11a wireless standards, while maintaining full backward compatibility with these standards.
  • 802.11g — applies to wireless LANs and is used for transmission over short distances at up to 54-Mbps in the 2.4 GHz bands.
  • 802.11n — 802.11n builds upon previous 802.11 standards by adding multiple-input multiple-output (MIMO). The additional transmitter and receiver antennas allow for increased data throughput through spatial multiplexing and increased range by exploiting the spatial diversity through coding schemes like Alamouti coding. The real speed would be 100 Mbit/s (even 250 Mbit/s in PHY level), and so up to 4-5 times faster than 802.11g.
  • 802.11ac — 802.11ac builds upon previous 802.11 standards, particularly the 802.11n standard, to deliver data rates of 433Mbps per spatial stream, or 1.3Gbps in a three-antenna (three stream) design. The 802.11ac specification operates only in the 5 GHz frequency range and features support for wider channels (80MHz and 160MHz) and beamforming capabilities by default to help achieve its higher wireless speeds.
  • 802.11ac Wave 2 — 802.11ac Wave 2 is an update for the original 802.11ac spec that uses MU-MIMO technology and other advancements to help increase theoretical maximum wireless speeds for the spec to 6.93 Gbps.
  • 802.11ad — 802.11ad is a wireless specification under development that will operate in the 60GHz frequency band and offer much higher transfer rates than previous 802.11 specs, with a theoretical maximum transfer rate of up to 7Gbps (Gigabits per second).
  • 802.11r -  802.11r, also called Fast Basic Service Set (BSS) Transition, supports VoWi-Fi handoff between access points to enable VoIP roaming on a Wi-Fi network with 802.1X authentication.
  • 802.1X — Not to be confused with 802.11x (which is the term used to describe the family of 802.11 standards) 802.1X is an IEEE standard for port-based Network Access Control that allows network administrators to restricted use of IEEE 802 LAN service access points to secure communication between authenticated and authorized devices. 

Is 5 GHz Wi-Fi Network Hardware Better than 2.4 GHz ?

Question: Is 5 GHz Wi-Fi Network Hardware Better than 2.4 GHz?

Wireless computer network equipment typically uses radio signals in either a 2.4 GHz range or a 5 GHz range. These numbers are advertised prominently on product packaging, but their meaning is often misunderstood. Is 5 GHz network hardware better than 2.4 GHz hardware just because it carries a bigger number?
Answer: No. 5 GHz hardware offers a few advantages over 2.4 GHz hardware, but in practice, 2.4 GHz is usually the better choice for home and other wireless local networks.

GHz and Network Speed

The GHz range of a wireless radio only partially relates to the speed of a wireless network. For example, 802.11a Wi-Fi hardware runs at 5 GHz but supports the same maximum data rate of 54 Mbps as standard 802.11g network that run at 2.4 GHz. A 5 GHz network can carry more data than a 2.4 GHz network assuming the electric power to the higher frequency radios is maintained at a higher level. However, some 802.11g network products match and even exceed this potential speed advantage of 5 GHz 802.11a by utilizing a pair of radios instead of one, increasing capacity up to 108 Mbps under the right conditions.
Advantage: Both

GHz and Network Range

The higher the frequency of a wireless signal, the shorter its range. Thus, 2.4 GHz networks cover a substantially larger range than 5 GHz wireless networks. In particular, the higher frequency wireless signals of 5 GHz networks do not penetrate solid objects nearly as well as do 2.4 GHz signals, limiting their reach inside homes. Advantage: 2.4 GHz.

GHz and Network Interference

You may notice your cordless phone, automatic garage door opener, or other home appliance also advertises 2.4 GHz signals on its packaging. Because this frequency range is commonly used in consumer products, it's more likely a 2.4 GHz home network will pick up interference from appliances than will a 5 GHz home network. Advantage: 5 GHz

GHz and Cost

Some people mistakenly believe 5 GHz network technology is newer or somehow more innovative than 2.4 GHz. In fact, both types of signaling have existed for many years and are both proven technologies. 802.11g Wi-Fi products that run at 2.4 GHz tend to cost less than 802.11a Wi-Fi products not because 802.11g is obsolete or less capable, but because 802.11g is much more popular and thus economical for manufacturers to support.
Advantage: 2.4 GHz

5 GHz vs 2.4 GHz - The Bottom Line

5 GHz and 2.4 GHz are different wireless signaling frequencies that each have advantages for computer networking. Higher frequency networks are not necessarily superior to lower frequency ones, however. So-called dual band hardware combines the best of both types of hardware by integrating both types of radios into the product.

Tuesday, 13 May 2014

How To Write a New Partition Boot Sector To a Windows 7/8/Vista System Partition

If the partition boot sector becomes corrupted or misconfigured in some way, Windows will not be able to start properly, prompting an error like BOOTMGR is Missing very early in the boot process.
The solution to a damaged partition boot sector is to overwrite it with a new, properly configured one using the bootrec command.
Important: The following instructions apply to Windows 8, Windows 7, and Windows Vista. Boot sector issues also occur in Windows XP but the solution involves a different process. See How To Write a New Partition Boot Sector To a Windows XP System Partition for help.
Difficulty: Easy
Time Required: It'll take around 15 minutes to write a new partition boot sector to your Windows system partition.
Here's How:
  1. Start Advanced Startup Options (Windows 8) or System Recovery Options (Windows 7 & Vista).
  2. Open Command Prompt.

    Note: The Command Prompt available from the Advanced Startup Options and System Recovery Options menus is similar to the one available from within Windows and works very similarly between operating systems.
  3. At the prompt, type the bootrec command as shown below and then press Enter:
    bootrec /fixboot
    The bootrec command will write a new partition boot sector to the current system partition. Any configuration or corruption issues with the partition boot sector that might have existed are now corrected.
  4. You should see the following message at the command line:
    The operation completed successfully.
    and then a blinking cursor at the prompt.
  5. Restart your computer.
    Assuming that a partition boot sector issue was the only problem, Windows should start normally now. If not, continue to troubleshoot whatever specific issue you're seeing that's preventing Windows from booting normally.
    Important: Depending on how you started Advanced Startup Options or System Recovery Options, you may need to remove a disc or flash drive before restarting.

More About Partition Boot Sectors