A USB drive, or “flash drive” as they’re sometimes known, is a small device with flash memory that acts as an external storage unit for data such as documents and pictures. If you’re using Windows, the steps to reformat a drive for use with a different file system or for different purposes are listed below.
Connect the USB drive to your computer after the machine has been turned on.
Allow the device to connect and wait for either a “ding” sound that confirms the device’s connection, or wait for a popup window on the bottom right of the taskbar to confirm that the driver for the device has successfully installed.
With the device connected, navigate to “My Computer” either in the Start menu or from your desktop.
With My Computer open, you should see a subsection of drives in addition to your main hard drive called “Devices with Removable Storage.”
Right click on the USB device you have connected and choose the “Format” option.
Choose your options from the drop down menus (or leave everything as default), and click “Start.”
Now, before we continue, it’s important to understand what all of the options for your drive formatting actually mean.
NTFS: An NTFS file system is designed for drives that generally handle file sizes bigger than 2 to 4GB. The NTFS file system is larger than the other options available and will take up extra space on the drive that you may not have. However, it is generally better at space management and can help organize larger files on a small device such as an external hard drive. NTFS is not recommended for small USB devices that are below 32GB, as it’s a bit slower than the other options.
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FAT/FAT32: FAT file systems take up much less space on USB devices but cannot handle files bigger than 4GB in size. If you’re planning on transferring movies that are bigger than 4GB or other files that are large in nature, FAT is not for you. However, if you only wish to transfer documents and small files, FAT is generally quicker than other options and uses less memory.
exFAT: Lastly, exFAT combines the organization and large file size capabilities of NTFS and combines it with the speed of FAT32. If you have the option to format as exFAT, do so.
Wednesday, January 4, 2012
Difference Between Cloud Computing and Grid Computing
Cloud Computing and Grid Computing are both forms of distributed computing. What do these approaches share in common and what are the differences?
Traditionally, computers use a local server or the hard disk in a personal computer to manage and process data. Cloud Computing is a radically new concept that leverage the power of internet to process and store data from a network of remote servers located anywhere in the world.
Grid computing, in contrast refers to combining or pooling computer resources from multiple domains to manage and process data. It is an extension of the conventional cluster computing concept.
Common Features between Grid and Cloud Computing
There is apparently only a thin line of difference separating cloud computing and grid computing, and these terms find use interchangeably in common parlance. Both methods are ways of distributed computing, or computing using remote resources over a network aimed at optimizing use of resources.
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Features common to both cloud and grid computing include:
Heavy use of abstraction, or masking the actual complex process taking place inside the system, and instead providing users with a simpler and easy to use interface
Scalability, or varying computing loads according to load demands. Both clouds and grids tend to draw more resources from the pool when the processes need so, and surrender the capacity or resources not needed to the common pool, for other users
Multi-tenancy and multitask, or the the ability to perform many different tasks simultaneously.
Differences between Grid and Cloud Computing
Although cloud computing and grid computing have much in common, they remain two different concepts. The major differences follow:
The major difference is in the architecture or modus-operandi. Cloud computing divides large tasks into chunks or small portions, disburse these portions across many machines for simultaneous processing, and then gather all of it. Grid computing on the other hand uses the best resource available from the pool without breaking up tasks. Local resources undertake the processing at the grid site, and wait in queue for access to the resource.
In clouds, the location of the processing center remain hidden, whereas in grids this is transparent, and users even have the option of selecting the location based on the list of available resources.
Grids operate in a project-oriented model, to address large-scale computing problems. Clouds, on the other hand address internet-scale computing problems.
Cloud computing and grid computing are not mutually exclusive, and many organizations use both together to speed up tasks. For instance, organizations use grid computing to select the best available resource to perform a task, and then apply cloud computing to execute the task faster using the different devices available within such resource.
Traditionally, computers use a local server or the hard disk in a personal computer to manage and process data. Cloud Computing is a radically new concept that leverage the power of internet to process and store data from a network of remote servers located anywhere in the world.
Grid computing, in contrast refers to combining or pooling computer resources from multiple domains to manage and process data. It is an extension of the conventional cluster computing concept.
Common Features between Grid and Cloud Computing
There is apparently only a thin line of difference separating cloud computing and grid computing, and these terms find use interchangeably in common parlance. Both methods are ways of distributed computing, or computing using remote resources over a network aimed at optimizing use of resources.
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Features common to both cloud and grid computing include:
Heavy use of abstraction, or masking the actual complex process taking place inside the system, and instead providing users with a simpler and easy to use interface
Scalability, or varying computing loads according to load demands. Both clouds and grids tend to draw more resources from the pool when the processes need so, and surrender the capacity or resources not needed to the common pool, for other users
Multi-tenancy and multitask, or the the ability to perform many different tasks simultaneously.
Differences between Grid and Cloud Computing
Although cloud computing and grid computing have much in common, they remain two different concepts. The major differences follow:
The major difference is in the architecture or modus-operandi. Cloud computing divides large tasks into chunks or small portions, disburse these portions across many machines for simultaneous processing, and then gather all of it. Grid computing on the other hand uses the best resource available from the pool without breaking up tasks. Local resources undertake the processing at the grid site, and wait in queue for access to the resource.
In clouds, the location of the processing center remain hidden, whereas in grids this is transparent, and users even have the option of selecting the location based on the list of available resources.
Grids operate in a project-oriented model, to address large-scale computing problems. Clouds, on the other hand address internet-scale computing problems.
Cloud computing and grid computing are not mutually exclusive, and many organizations use both together to speed up tasks. For instance, organizations use grid computing to select the best available resource to perform a task, and then apply cloud computing to execute the task faster using the different devices available within such resource.
Classless Inter-Domain Routing (CIDR) Subnetting
“Slash notation” is the standard way to express an IP Address and Subnet Mask together outside traditional A, B, and C classes. Network professionals will refer to a Subnet Mask of “255.255.255.0” as “slash 24”, but how does one number translate to the other? Instead of writing out a full IP Address and Subnet Mask such as “192.168.100.2 255.255.255.0” it will be written as “192.168.100.2/24” which is much shorter and easier to communicate.
The number after the “/” is the number of binary ones in the Subnet Mask. A “/24” subnet mask is simply 24 binary ones in a row, adding up to “255.255.255.0”.
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Example of Slash Notation
H = Host Bit, N = Network Bit
# of new subnets = 2^N bits borrowed
# of usable addresses = (2^H bits)-2 subtract two for unusable Network ID and Broadcast ID
11111111 . 11111111 . 11111111 . 00000000 = /24 = 255.255.255.0
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NNNNNNNN . NNNNNNNN . NNNNNNNN . HHHHHHH (no H bits borrowed)
2^N bits borrowed = 1 or 2^0 = 1 subnet
(2^H bits)-2 = 254 or (2^8)-2 = 254 hosts / subnet
11111111 . 11111111 . 11111111 . 10000000 = /25 = 255.255.255.128
NNNNNNNN . NNNNNNNN . NNNNNNNN . NHHHHHH (one H bit borrowed)
2^N bits borrowed = 2 or 2^1 = 2 subnets
(2^H bits)-2 = 126 or (2^7)-2 = 126 hosts / subnet
11111111 . 11111111 . 11111111 . 11000000 = /26 = 255.255.255.192
NNNNNNNN . NNNNNNNN . NNNNNNNN . NNHHHHH (two H bits borrowed)
2^N bits borrowed = 4 or 2^2 = 4 subnets
(2^H bits)-2 = 62 or (2^6)-2 = 62 hosts / subnet
...continuing…
11111111 . 11111111 . 11111111 . 11111100 = /30 = 255.255.255.252
NNNNNNNN . NNNNNNNN . NNNNNNNN . NNNNNNHH (six H bits borrowed)
2^N bits borrowed = 64 or 2^6 = 64 subnets
(2^H bits)-2 = 2 or (2^2)-2 = 2 hosts / subnet
A “/30” subnet is the last usable subnet mask, allowing for only two usable hosts. This is commonly used in point-to-point links between sites and routers to preserve IP addresses. “/31” and “/32” subnet masks are unusable because they allow for less than two usable host addresses.
Basic Subnetting Exercise
For example, given the “192.168.100.0/24” subnet but needing two smaller subnets instead, one could cut the “/24” subnet into two separate “/25” subnets by “borrowing” one bit from the available host bits for networks.
-------------------------------------------------------------
Subnet A (126 Usable IPs, 2 unusable IPs)
192.168.100.0/25 Network ID
192.168.100.1/25 First Usable Host IP
…Usable Host IPs…
192.168.100.126/25 Last Usable Host IP
192.168.100.127/25 Broadcast ID
-------------------------------------------------------------
Subnet B (126 Usable IPs, 2 unusable IPs)
192.168.100.128/25 Network ID
192.168.100.129/25 First Usable Host IP
…Usable Host IPs…
192.168.100.254/25 Last Usable Host IP
192.168.100.255/25 Broadcast ID
-------------------------------------------------------------
Instead of having one large “/24” subnet and procuring another to create the second subnet, the “/24” with 1 network, 254 usable and 2 unusable IP addresses was cut up into a “/25” with 2 networks each having 126 usable and 2 unusable IP addresses.
Unequal CIDR Subnetting Exercise
CIDR is a balancing act between the number of subnets needed and the number of usable IP addresses in those subnets. Let’s do an exercise with unequal CIDR subnets. Given the same “192.168.100.0/24” subnet create two subnets. One subnet must support 60 usable hosts, the other must support 7 usable hosts, saving as many IP addresses for future use as possible.
Standard practice is to configure the larger block of addresses first – the 60 host block. Borrowing 1 host bit will create a subnet having 126 usable addresses (too much waste). Borrowing 2 host bits will create a subnet having 62 usable address – just right. Borrowing 3 host bits will create a subnet having 30 usable addresses – not enough, so this first block will be a “/26” subnet.
-------------------------------------------------------------
Subnet A (62 Usable IPs, 2 unusable IPs)
192.168.100.0/26 Network ID
192.168.100.1/26 First Usable Host IP
…Usable Host IPs…
192.168.100.62/26 Last Usable Host IP
192.168.100.63/26 Broadcast ID
-------------------------------------------------------------
Untouched IPs still available
192.168.100.64 to 192.168.100.255
-------------------------------------------------------------
Now subnet the second block – only 7 hosts. Borrowing 3 host bits will create a subnet having 30 usable addresses – too much. Borrowing 4 host bits will create a subnet having 14 usable address – a little more than needed. Borrowing 5 host bits will create a subnet having 6 usable address – not enough, so we’ll have to borrow 4 bits and have a little left over (no big deal). Here’s how the subnet table looks now…
-------------------------------------------------------------
Subnet A (62 Usable IPs, 2 unusable IPs)
192.168.100.0/26 Network ID
192.168.100.1/26 First Usable Host IP
…Usable Host IPs…
192.168.100.62/26 Last Usable Host IP
192.168.100.63/26 Broadcast ID
-------------------------------------------------------------
Subnet B (14 Usable IPs, 2 unusable IPs)
192.168.100.64/28 Network ID
192.168.100.65/28 First Usable Host IP
…Usable Host IPs…
192.168.100.78/28 Last Usable Host IP
192.168.100.79/28 Broadcast ID
-------------------------------------------------------------
Untouched addresses still available for further subnetting
192.168.100.80 to 192.168.100.255
The number after the “/” is the number of binary ones in the Subnet Mask. A “/24” subnet mask is simply 24 binary ones in a row, adding up to “255.255.255.0”.
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Example of Slash Notation
H = Host Bit, N = Network Bit
# of new subnets = 2^N bits borrowed
# of usable addresses = (2^H bits)-2 subtract two for unusable Network ID and Broadcast ID
11111111 . 11111111 . 11111111 . 00000000 = /24 = 255.255.255.0
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NNNNNNNN . NNNNNNNN . NNNNNNNN . HHHHHHH (no H bits borrowed)
2^N bits borrowed = 1 or 2^0 = 1 subnet
(2^H bits)-2 = 254 or (2^8)-2 = 254 hosts / subnet
11111111 . 11111111 . 11111111 . 10000000 = /25 = 255.255.255.128
NNNNNNNN . NNNNNNNN . NNNNNNNN . NHHHHHH (one H bit borrowed)
2^N bits borrowed = 2 or 2^1 = 2 subnets
(2^H bits)-2 = 126 or (2^7)-2 = 126 hosts / subnet
11111111 . 11111111 . 11111111 . 11000000 = /26 = 255.255.255.192
NNNNNNNN . NNNNNNNN . NNNNNNNN . NNHHHHH (two H bits borrowed)
2^N bits borrowed = 4 or 2^2 = 4 subnets
(2^H bits)-2 = 62 or (2^6)-2 = 62 hosts / subnet
...continuing…
11111111 . 11111111 . 11111111 . 11111100 = /30 = 255.255.255.252
NNNNNNNN . NNNNNNNN . NNNNNNNN . NNNNNNHH (six H bits borrowed)
2^N bits borrowed = 64 or 2^6 = 64 subnets
(2^H bits)-2 = 2 or (2^2)-2 = 2 hosts / subnet
A “/30” subnet is the last usable subnet mask, allowing for only two usable hosts. This is commonly used in point-to-point links between sites and routers to preserve IP addresses. “/31” and “/32” subnet masks are unusable because they allow for less than two usable host addresses.
Basic Subnetting Exercise
For example, given the “192.168.100.0/24” subnet but needing two smaller subnets instead, one could cut the “/24” subnet into two separate “/25” subnets by “borrowing” one bit from the available host bits for networks.
-------------------------------------------------------------
Subnet A (126 Usable IPs, 2 unusable IPs)
192.168.100.0/25 Network ID
192.168.100.1/25 First Usable Host IP
…Usable Host IPs…
192.168.100.126/25 Last Usable Host IP
192.168.100.127/25 Broadcast ID
-------------------------------------------------------------
Subnet B (126 Usable IPs, 2 unusable IPs)
192.168.100.128/25 Network ID
192.168.100.129/25 First Usable Host IP
…Usable Host IPs…
192.168.100.254/25 Last Usable Host IP
192.168.100.255/25 Broadcast ID
-------------------------------------------------------------
Instead of having one large “/24” subnet and procuring another to create the second subnet, the “/24” with 1 network, 254 usable and 2 unusable IP addresses was cut up into a “/25” with 2 networks each having 126 usable and 2 unusable IP addresses.
Unequal CIDR Subnetting Exercise
CIDR is a balancing act between the number of subnets needed and the number of usable IP addresses in those subnets. Let’s do an exercise with unequal CIDR subnets. Given the same “192.168.100.0/24” subnet create two subnets. One subnet must support 60 usable hosts, the other must support 7 usable hosts, saving as many IP addresses for future use as possible.
Standard practice is to configure the larger block of addresses first – the 60 host block. Borrowing 1 host bit will create a subnet having 126 usable addresses (too much waste). Borrowing 2 host bits will create a subnet having 62 usable address – just right. Borrowing 3 host bits will create a subnet having 30 usable addresses – not enough, so this first block will be a “/26” subnet.
-------------------------------------------------------------
Subnet A (62 Usable IPs, 2 unusable IPs)
192.168.100.0/26 Network ID
192.168.100.1/26 First Usable Host IP
…Usable Host IPs…
192.168.100.62/26 Last Usable Host IP
192.168.100.63/26 Broadcast ID
-------------------------------------------------------------
Untouched IPs still available
192.168.100.64 to 192.168.100.255
-------------------------------------------------------------
Now subnet the second block – only 7 hosts. Borrowing 3 host bits will create a subnet having 30 usable addresses – too much. Borrowing 4 host bits will create a subnet having 14 usable address – a little more than needed. Borrowing 5 host bits will create a subnet having 6 usable address – not enough, so we’ll have to borrow 4 bits and have a little left over (no big deal). Here’s how the subnet table looks now…
-------------------------------------------------------------
Subnet A (62 Usable IPs, 2 unusable IPs)
192.168.100.0/26 Network ID
192.168.100.1/26 First Usable Host IP
…Usable Host IPs…
192.168.100.62/26 Last Usable Host IP
192.168.100.63/26 Broadcast ID
-------------------------------------------------------------
Subnet B (14 Usable IPs, 2 unusable IPs)
192.168.100.64/28 Network ID
192.168.100.65/28 First Usable Host IP
…Usable Host IPs…
192.168.100.78/28 Last Usable Host IP
192.168.100.79/28 Broadcast ID
-------------------------------------------------------------
Untouched addresses still available for further subnetting
192.168.100.80 to 192.168.100.255
Monday, January 2, 2012
NetBIOS
Definition: NetBIOS is a software protocol for providing computer communication services on local networks. Microsoft Windows uses NetBIOS on Ethernet or Token Ring networks.
Software applications on a NetBIOS network locate each other via their NetBIOS names. A NetBIOS name is up to 16 characters long and in Windows, separate from the computer name. Applications on other computers access NetBIOS names over UDP port 137. The Windows Internet Naming Service (WINS) provides name resolution services for NetBIOS.
Two applications start a NetBIOS session when one (the client) sends a command to "Call" another (the server) over TCP port 139 on a remote computer. Both sides issue "Send" and "Receive" commands to deliver messages in both directions. The "Hang-Up" command terminates a NetBIOS session.
NetBIOS also supports connectionless communications via UDP datagrams. Applications listen on UDP port 138 to receive NetBIOS datagrams.
NetBIOS and NetBEUI are separate but related technologies. NetBEUI extends NetBIOS with additional networking capabilities.
Software applications on a NetBIOS network locate each other via their NetBIOS names. A NetBIOS name is up to 16 characters long and in Windows, separate from the computer name. Applications on other computers access NetBIOS names over UDP port 137. The Windows Internet Naming Service (WINS) provides name resolution services for NetBIOS.
Two applications start a NetBIOS session when one (the client) sends a command to "Call" another (the server) over TCP port 139 on a remote computer. Both sides issue "Send" and "Receive" commands to deliver messages in both directions. The "Hang-Up" command terminates a NetBIOS session.
NetBIOS also supports connectionless communications via UDP datagrams. Applications listen on UDP port 138 to receive NetBIOS datagrams.
NetBIOS and NetBEUI are separate but related technologies. NetBEUI extends NetBIOS with additional networking capabilities.
satellite Internet
Satellite Internet service covers areas where DSL and cable access is unavailable. Satellite offers less network bandwidth compared to DSL or cable, however. In addition, the long delays required to transmit data between the satellite and the ground stations tend to create high network latency, causing a sluggish performance experience in some cases. Network applications like VPN and online gaming may not function properly over satellite Internet connections due to these latency issues.
Older residential satellite Internet services supported only "one-way" downloads over the satellite link, requiring a telephone modem for uploading. All newer satellite services support full "two-way" satellite links.
Satellite Internet service does not necessary utilitize WiMax. WiMax technology supplies one method to deliver high-speed Internet service over wireless links, but satellite providers may implement their systems differently.
Older residential satellite Internet services supported only "one-way" downloads over the satellite link, requiring a telephone modem for uploading. All newer satellite services support full "two-way" satellite links.
Satellite Internet service does not necessary utilitize WiMax. WiMax technology supplies one method to deliver high-speed Internet service over wireless links, but satellite providers may implement their systems differently.
CIDR - Classless Inter-Domain Routing
CIDR stands for Classless Inter-Domain Routing. CIDR was developed in the 1990s as a standard scheme for routing network traffic across the Internet.
Why Use CIDR?
Before CIDR technology was developed, Internet routers managed network traffic based on the class of IP addresses. In this system, the value of an IP address determines its subnetwork for the purposes of routing.
CIDR is an alternative to traditional IP subnetting that organizes IP addresses into subnetworks independent of the value of the addresses themselves. CIDR is also known as supernetting as it effectively allows multiple subnets to be grouped together for network routing.
CIDR Notation
CIDR specifies an IP address range using a combination of an IP address and its associated network mask. CIDR notation uses the following format - xxx.xxx.xxx.xxx/n
xxx.xxx.xxx.xxx/n
where n is the number of (leftmost) '1' bits in the mask. For example, 192.168.12.0/23
192.168.12.0/23
applies the network mask 255.255.254.0 to the 192.168 network, starting at 192.168.12.0. This notation represents the address range 192.168.12.0 - 192.168.13.255. Compared to traditional class-based networking, 192.168.12.0/23 represents an aggregation of the two Class C subnets 192.168.12.0 and 192.168.13.0 each having a subnet mask of 255.255.255.0. In other words, 192.168.12.0/23 = 192.168.12.0/24 + 192.168.13.0/24
Additionally, CIDR supports Internet address allocation and message routing independent of the traditional class of a given IP address range. For example,
10.4.12.0/22
represents the address range 10.4.12.0 - 10.4.15.255 (network mask 255.255.252.0). This allocates the equivalent of four Class C networks within the much larger Class A space.
You will sometimes see CIDR notation used even for non-CIDR networks. In non-CIDR IP subnetting, however, the value of n is restricted to either 8 (Class A), 16 (Class B) or 24 (Class C). Examples:
10.0.0.0/8
172.16.0.0/16
192.168.3.0/24
How CIDR Works
CIDR implementations require certain support be embedded within the network routing protocols. When first implemented on the Internet, the core routing protocols like BGP (Border Gateway Protocol) and OSPF (Open Shortest Path First) were updated to support CIDR. Obsolete or less popular routing protocols may not support CIDR.
CIDR aggregation requires the network segments involved to be contiguous (numerically adjacent) in the address space. CIDR cannot, for example, aggregate 192.168.12.0 and 192.168.15.0 into a single route unless the intermediate .13 and .14 address ranges are included (i.e., the 192.168.12/22 network).
Internet WAN or backbone routers (those that manage traffic between Internet Service Providers) all generally support CIDR to achieve the goal of conserving IP address space. Mainstream consumer routers often do not support CIDR, therefore private networks (including home networks) and even small public networks (LANs) often do not employ it.
Why Use CIDR?
Before CIDR technology was developed, Internet routers managed network traffic based on the class of IP addresses. In this system, the value of an IP address determines its subnetwork for the purposes of routing.
CIDR is an alternative to traditional IP subnetting that organizes IP addresses into subnetworks independent of the value of the addresses themselves. CIDR is also known as supernetting as it effectively allows multiple subnets to be grouped together for network routing.
CIDR Notation
CIDR specifies an IP address range using a combination of an IP address and its associated network mask. CIDR notation uses the following format - xxx.xxx.xxx.xxx/n
xxx.xxx.xxx.xxx/n
where n is the number of (leftmost) '1' bits in the mask. For example, 192.168.12.0/23
192.168.12.0/23
applies the network mask 255.255.254.0 to the 192.168 network, starting at 192.168.12.0. This notation represents the address range 192.168.12.0 - 192.168.13.255. Compared to traditional class-based networking, 192.168.12.0/23 represents an aggregation of the two Class C subnets 192.168.12.0 and 192.168.13.0 each having a subnet mask of 255.255.255.0. In other words, 192.168.12.0/23 = 192.168.12.0/24 + 192.168.13.0/24
Additionally, CIDR supports Internet address allocation and message routing independent of the traditional class of a given IP address range. For example,
10.4.12.0/22
represents the address range 10.4.12.0 - 10.4.15.255 (network mask 255.255.252.0). This allocates the equivalent of four Class C networks within the much larger Class A space.
You will sometimes see CIDR notation used even for non-CIDR networks. In non-CIDR IP subnetting, however, the value of n is restricted to either 8 (Class A), 16 (Class B) or 24 (Class C). Examples:
10.0.0.0/8
172.16.0.0/16
192.168.3.0/24
How CIDR Works
CIDR implementations require certain support be embedded within the network routing protocols. When first implemented on the Internet, the core routing protocols like BGP (Border Gateway Protocol) and OSPF (Open Shortest Path First) were updated to support CIDR. Obsolete or less popular routing protocols may not support CIDR.
CIDR aggregation requires the network segments involved to be contiguous (numerically adjacent) in the address space. CIDR cannot, for example, aggregate 192.168.12.0 and 192.168.15.0 into a single route unless the intermediate .13 and .14 address ranges are included (i.e., the 192.168.12/22 network).
Internet WAN or backbone routers (those that manage traffic between Internet Service Providers) all generally support CIDR to achieve the goal of conserving IP address space. Mainstream consumer routers often do not support CIDR, therefore private networks (including home networks) and even small public networks (LANs) often do not employ it.
Wi-Fi Hotspots
A Wi-Fi hotspot is a wireless access point that provides Internet access to network devices in public locations such as downtown centers, cafes, airports and hotels. Businesses and schools are increasingly using Wi-Fi hotspots for their internal (intranet) networks. Home wireless networks also use similar Wi-Fi technology.
Requirements to Use Wi-Fi Hotspots
Computers (and other devices) connect to hotspots using a Wi-Fi network adapter. Newer laptop computers contain built-in adapters, but most other computers do not. Wi-Fi network adapters can be purchased and installed separately. Depending on the type of computer and personal preferences, USB, PC Card, ExpressCard, or even PCI card adapters can be used.
Public Wi-Fi hotspots normally require a paid subscription. The sign-up process involves providing credit card information online or by phone and choosing a service plan. Some service providers offer plans that work at thousands of hotspots throughout the country.
A few pieces of technical information are also required to access Wi-Fi hotspots. The network name (also called SSID) distinguishes hotspot networks from each other. Encryption keys (a long series of letters and numbers) scramble the network traffic to and from a hotspot; most businesses require these as well. Service providers supply this profile information for their hotspots.
Finding Wi-Fi Hotspots
Computers can automatically scan for hotspots within range of their wireless signal. These scans identify the network name (SSID) of the hotspot allowing the computer to initiate a connection.
Instead of using a computer to find hotspots, some people prefer to use a separate gadget called a Wi-Fi finder. These small devices scan for hotspot signals similarly to computers, and many provide some indication of signal strength to help pinpoint their exact location.
Before traveling to a far-away place, the location of Wi-Fi hotspots can be found using online wireless hotspot finder services.
Connect To Wi-Fi Hotspots
The process for connecting to a Wi-Fi hotspot works similarly on home, business and public wireless networks. With the profile (network name and encryption settings) applied on the wireless network adapter, you initiate the connection from your computer operating system (or software that was supplied with the network adapter). Paid or restricted hotspot services will require you to log in with a user name and password the first time you access the Internet.
Dangers of Wi-Fi Hotspots
Although few incidents of hotspot security issues are reported in the press, many people remain skeptical of their safety. Some caution is justified as a hacker with good technical skills can break into your computer through a hotspot and potentially access your personal data.
Taking a few basic precautions will ensure reasonable safety when using Wi-Fi hotspots. First, research the public hotspot service providers and choose only reputable ones who use strong security settings on their networks. Next, ensure you do not accidentally connect to non-preferred hotspots by checking your computer's settings. Finally, be aware of your surroundings and watch for suspicious individuals in the vicinity who may be reading your screen or even plotting to steal your computer.
Requirements to Use Wi-Fi Hotspots
Computers (and other devices) connect to hotspots using a Wi-Fi network adapter. Newer laptop computers contain built-in adapters, but most other computers do not. Wi-Fi network adapters can be purchased and installed separately. Depending on the type of computer and personal preferences, USB, PC Card, ExpressCard, or even PCI card adapters can be used.
Public Wi-Fi hotspots normally require a paid subscription. The sign-up process involves providing credit card information online or by phone and choosing a service plan. Some service providers offer plans that work at thousands of hotspots throughout the country.
A few pieces of technical information are also required to access Wi-Fi hotspots. The network name (also called SSID) distinguishes hotspot networks from each other. Encryption keys (a long series of letters and numbers) scramble the network traffic to and from a hotspot; most businesses require these as well. Service providers supply this profile information for their hotspots.
Finding Wi-Fi Hotspots
Computers can automatically scan for hotspots within range of their wireless signal. These scans identify the network name (SSID) of the hotspot allowing the computer to initiate a connection.
Instead of using a computer to find hotspots, some people prefer to use a separate gadget called a Wi-Fi finder. These small devices scan for hotspot signals similarly to computers, and many provide some indication of signal strength to help pinpoint their exact location.
Before traveling to a far-away place, the location of Wi-Fi hotspots can be found using online wireless hotspot finder services.
Connect To Wi-Fi Hotspots
The process for connecting to a Wi-Fi hotspot works similarly on home, business and public wireless networks. With the profile (network name and encryption settings) applied on the wireless network adapter, you initiate the connection from your computer operating system (or software that was supplied with the network adapter). Paid or restricted hotspot services will require you to log in with a user name and password the first time you access the Internet.
Dangers of Wi-Fi Hotspots
Although few incidents of hotspot security issues are reported in the press, many people remain skeptical of their safety. Some caution is justified as a hacker with good technical skills can break into your computer through a hotspot and potentially access your personal data.
Taking a few basic precautions will ensure reasonable safety when using Wi-Fi hotspots. First, research the public hotspot service providers and choose only reputable ones who use strong security settings on their networks. Next, ensure you do not accidentally connect to non-preferred hotspots by checking your computer's settings. Finally, be aware of your surroundings and watch for suspicious individuals in the vicinity who may be reading your screen or even plotting to steal your computer.
Home Network Backup
A home network backup system maintains copies of your personal electronic data files in case of computer failures, theft or disasters. You can manage your own home network backups or choose to use an online service. Considering the impact of possibly losing irreplaceable family photos and documents, the time and money you spend on network backups is almost certainly a worthwhile investment.
Types of Home Network Backup
Several different methods exist for setting up and organizing backups using your home computer network: backups to CD-ROM or DVD-ROM discs
network backups to a local server
online backups to a remote hosting service
backups to CD-ROM or DVD-ROM discs
network backups to a local server
online backups to a remote hosting service
Backup to Discs
One simple way to back up your data is to "burn" copies onto optical (CD-ROM or DVD-ROM) discs. Using this method, you can manually choose the individual files and folders you want to back up from each computer, then use the computer's CD / DVD writing program to make file copies. If all of your computers have a CD-ROM / DVD-ROM writer, you do not even need to access the network as part of the backup procedure.
Most homes have at least one computer on the network without its own disc writer, however. For these, you can set up file sharing and remotely transfer data onto the optical disc over the home network.
More - How to Share Files in Windows
Network Backup to a Local Server
Instead of burning multiple disks on possibly several different computers, consider setting up a backup server on your home network. A backup server contains a large hard disk drive (sometimes more than one for increased reliability) and has network access to receive files from the other home computers.
Several companies manufacture Network Attached Storage (NAS) devices that function as simple backup servers. Alternatively, more technically inclined homeowners may opt to set up their own backup server using an ordinary computer and home network backup software.
More - Top NAS Drives for Home Networks
Network Backup to a Remote Hosting Service
Several Internet sites offer remote data backup services. Instead of making copies of data within the home as with the above methods, these online services copy files from the home network to their servers over the Internet and store subscribers' data in their protected facilities.
Types of Home Network Backup
Several different methods exist for setting up and organizing backups using your home computer network: backups to CD-ROM or DVD-ROM discs
network backups to a local server
online backups to a remote hosting service
backups to CD-ROM or DVD-ROM discs
network backups to a local server
online backups to a remote hosting service
Backup to Discs
One simple way to back up your data is to "burn" copies onto optical (CD-ROM or DVD-ROM) discs. Using this method, you can manually choose the individual files and folders you want to back up from each computer, then use the computer's CD / DVD writing program to make file copies. If all of your computers have a CD-ROM / DVD-ROM writer, you do not even need to access the network as part of the backup procedure.
Most homes have at least one computer on the network without its own disc writer, however. For these, you can set up file sharing and remotely transfer data onto the optical disc over the home network.
More - How to Share Files in Windows
Network Backup to a Local Server
Instead of burning multiple disks on possibly several different computers, consider setting up a backup server on your home network. A backup server contains a large hard disk drive (sometimes more than one for increased reliability) and has network access to receive files from the other home computers.
Several companies manufacture Network Attached Storage (NAS) devices that function as simple backup servers. Alternatively, more technically inclined homeowners may opt to set up their own backup server using an ordinary computer and home network backup software.
More - Top NAS Drives for Home Networks
Network Backup to a Remote Hosting Service
Several Internet sites offer remote data backup services. Instead of making copies of data within the home as with the above methods, these online services copy files from the home network to their servers over the Internet and store subscribers' data in their protected facilities.
Connect Two Home Computers for File Sharing
The simplest kind of home network contains exactly two computers. You can use this kind of network to share files, a printer or another peripheral device, and even an Internet connection. To connect two computers for sharing these and other network resources, consider the options described below.
Connecting Two Computers Directly With Cable
The traditional method to network two computers involves making a dedicated link by plugging one cable into the two systems. Several alternatives exist for networking two computers in this manner: Ethernet crossover cable
Null modem serial cable or parallel peripheral cable
Special-purpose USB cables
Ethernet crossover cable
Null modem serial cable or parallel peripheral cable
Special-purpose USB cables
Ethernet - Of the above choices, the Ethernet method is preferred as it supports a reliable, high-speed connection with minimal configuration required. Additionally, Ethernet technology offers the most general-purpose solution, allowing networks with more than two computers to be built fairly easily later. If one of your computers possesses an Ethernet adapter but the other has USB, an Ethernet crossover cable can still be used by first plugging a USB-to-Ethernet converter unit into the computer's USB port.
See also: Ethernet crossover cables
Serial and parallel - This type of cabling, called Direct Cable Connection (DCC) when using Microsoft Windows, offers lower performance but offers the same basic functionality as Ethernet cables. You may prefer this option if you have such cables readily available and network speed is not a concern. Serial and parallel cables are never used to network more than two computers.
USB - Ordinary USB cables must not be used to connect two computers directly to each other. Attempting to do so can electrically damage the computers! However, special USB cables designed for direct connection exist that can be used safely. You may prefer this option over others if your computers lack functional Ethernet network adapters.
To make dedicated connections with Ethernet, USB, serial or parallel cables requires
each computer have a functioning network interface with an external jack for the cable, and
the network settings on each computer appropriately configured
One phone line or power cord cannot be used to directly connect two computers to each other for networking.
Connecting Two Computers Directly With Cable
The traditional method to network two computers involves making a dedicated link by plugging one cable into the two systems. Several alternatives exist for networking two computers in this manner: Ethernet crossover cable
Null modem serial cable or parallel peripheral cable
Special-purpose USB cables
Ethernet crossover cable
Null modem serial cable or parallel peripheral cable
Special-purpose USB cables
Ethernet - Of the above choices, the Ethernet method is preferred as it supports a reliable, high-speed connection with minimal configuration required. Additionally, Ethernet technology offers the most general-purpose solution, allowing networks with more than two computers to be built fairly easily later. If one of your computers possesses an Ethernet adapter but the other has USB, an Ethernet crossover cable can still be used by first plugging a USB-to-Ethernet converter unit into the computer's USB port.
See also: Ethernet crossover cables
Serial and parallel - This type of cabling, called Direct Cable Connection (DCC) when using Microsoft Windows, offers lower performance but offers the same basic functionality as Ethernet cables. You may prefer this option if you have such cables readily available and network speed is not a concern. Serial and parallel cables are never used to network more than two computers.
USB - Ordinary USB cables must not be used to connect two computers directly to each other. Attempting to do so can electrically damage the computers! However, special USB cables designed for direct connection exist that can be used safely. You may prefer this option over others if your computers lack functional Ethernet network adapters.
To make dedicated connections with Ethernet, USB, serial or parallel cables requires
each computer have a functioning network interface with an external jack for the cable, and
the network settings on each computer appropriately configured
One phone line or power cord cannot be used to directly connect two computers to each other for networking.
A New Wireless Sensor Network from GreenGoose
A start-up company with an egg theme is looking to break into (crack?) wireless sensor networks and have made their first product available for the new year. GreenGoose wireless sensors for dogs connect to (well, the dog of course, but then also) a wireless radio frequency (RF, not Wi-Fi) goose-egg-shaped base station (pictured at right) that plugs into the home broadband router via Ethernet cable. The company is also hatching (!) future plans to expand their network with additional types of personal information sensors and technology.
Some in the industry are expecting new kinds of networked wearable computing devices like this to be popular in 2012. Traditional home automation sensors are good for monitoring things like lighting, rain, doors and movement but are installed at fixed locations rather than being attached to animate objects. Wearable gadgets to complement home automation systems were hyped about a decade ago but failed to gain popular acceptance. This time around, with the technology improved, the situation could be different... as long as companies focus on practical rather than frivolous applications.
Some in the industry are expecting new kinds of networked wearable computing devices like this to be popular in 2012. Traditional home automation sensors are good for monitoring things like lighting, rain, doors and movement but are installed at fixed locations rather than being attached to animate objects. Wearable gadgets to complement home automation systems were hyped about a decade ago but failed to gain popular acceptance. This time around, with the technology improved, the situation could be different... as long as companies focus on practical rather than frivolous applications.
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