IP Addressing and Subnetting for New Users

Introduction

This document gives you basic information needed in order to configure your router for routing IP, such as how addresses are broken down and how subnetting works. You learn how to assign each interface on the router an IP address with a unique subnet. There are many examples to help tie everything together.
Prerequisites
Requirements

Cisco recommends that you have knowledge of these topics:


Basic understanding of binary and decimal numbers.
Components Used

This document is not restricted to specific software and hardware versions.
Additional Information

If definitions are helpful to you, use these vocabulary terms to get you started:


Address—The unique number ID assigned to one host or interface in a network.


Subnet—A portion of a network sharing a particular subnet address.


Subnet mask—A 32-bit combination used to describe which portion of an address refers to the subnet and which part refers to the host.


Interface—A network connection.

If you have already received your legitimate address(es) from the Internet Network Information Center (InterNIC), you are ready to begin. If you do not plan to connect to the Internet, Cisco strongly suggests that you use reserved addresses from RFC 1918 .
Conventions

Refer to Cisco Technical Tips Conventions for more information on document conventions.
Understanding IP Addresses

An IP address is an address used in order to uniquely identify a device on an IP network. The address is made up of 32 binary bits, which can be divisible into a network portion and host portion with the help of a subnet mask. The 32 binary bits are broken into four octets (1 octet = 8 bits). Each octet is converted to decimal and separated by a period (dot). For this reason, an IP address is said to be expressed in dotted decimal format (for example, 172.16.81.100). The value in each octet ranges from 0 to 255 decimal, or 00000000 - 11111111 binary.

Here is how binary octets convert to decimal: The right most bit, or least significant bit, of an octet holds a value of 20. The bit just to the left of that holds a value of 21. This continues until the left-most bit, or most significant bit, which holds a value of 27. So if all binary bits are a one, the decimal equivalent would be 255 as shown here:
1 1 1 1 1 1 1 1
128 64 32 16 8 4 2 1 (128+64+32+16+8+4+2+1=255)

Here is a sample octet conversion when not all of the bits are set to 1.
0 1 0 0 0 0 0 1
0 64 0 0 0 0 0 1 (0+64+0+0+0+0+0+1=65)

And this is sample shows an IP address represented in both binary and decimal.
10. 1. 23. 19 (decimal)
00001010.00000001.00010111.00010011 (binary)

These octets are broken down to provide an addressing scheme that can accommodate large and small networks. There are five different classes of networks, A to E. This document focuses on addressing classes A to C, since classes D and E are reserved and discussion of them is beyond the scope of this document.

Note: Also note that the terms "Class A, Class B" and so on are used in this document to help facilitate the understanding of IP addressing and subnetting. These terms are rarely used in the industry anymore because of the introduction of classless interdomain routing (CIDR).

Given an IP address, its class can be determined from the three high-order bits. Figure 1 shows the significance in the three high order bits and the range of addresses that fall into each class. For informational purposes, Class D and Class E addresses are also shown.
Figure 1




In a Class A address, the first octet is the network portion, so the Class A example in Figure 1 has a major network address of 1.0.0.0 - 127.255.255.255. Octets 2, 3, and 4 (the next 24 bits) are for the network manager to divide into subnets and hosts as he/she sees fit. Class A addresses are used for networks that have more than 65,536 hosts (actually, up to 16777214 hosts!).

In a Class B address, the first two octets are the network portion, so the Class B example in Figure 1 has a major network address of 128.0.0.0 - 191.255.255.255. Octets 3 and 4 (16 bits) are for local subnets and hosts. Class B addresses are used for networks that have between 256 and 65534 hosts.

In a Class C address, the first three octets are the network portion. The Class C example in Figure 1 has a major network address of 192.0.0.0 - 233.255.255.255. Octet 4 (8 bits) is for local subnets and hosts - perfect for networks with less than 254 hosts.
Network Masks

A network mask helps you know which portion of the address identifies the network and which portion of the address identifies the node. Class A, B, and C networks have default masks, also known as natural masks, as shown here:
Class A: 255.0.0.0
Class B: 255.255.0.0
Class C: 255.255.255.0

An IP address on a Class A network that has not been subnetted would have an address/mask pair similar to: 8.20.15.1 255.0.0.0. To see how the mask helps you identify the network and node parts of the address, convert the address and mask to binary numbers.
8.20.15.1 = 00001000.00010100.00001111.00000001
255.0.0.0 = 11111111.00000000.00000000.00000000

Once you have the address and the mask represented in binary, then identifying the network and host ID is easier. Any address bits which have corresponding mask bits set to 1 represent the network ID. Any address bits that have corresponding mask bits set to 0 represent the node ID.
8.20.15.1 = 00001000.00010100.00001111.00000001
255.0.0.0 = 11111111.00000000.00000000.00000000
-----------------------------------
net id | host id

netid = 00001000 = 8
hostid = 00010100.00001111.00000001 = 20.15.1
Understanding Subnetting

Subnetting allows you to create multiple logical networks that exist within a single Class A, B, or C network. If you do not subnet, you are only able to use one network from your Class A, B, or C network, which is unrealistic.

Each data link on a network must have a unique network ID, with every node on that link being a member of the same network. If you break a major network (Class A, B, or C) into smaller subnetworks, it allows you to create a network of interconnecting subnetworks. Each data link on this network would then have a unique network/subnetwork ID. Any device, or gateway, connecting n networks/subnetworks has n distinct IP addresses, one for each network / subnetwork that it interconnects.

In order to subnet a network, extend the natural mask using some of the bits from the host ID portion of the address to create a subnetwork ID. For example, given a Class C network of 204.17.5.0 which has a natural mask of 255.255.255.0, you can create subnets in this manner:
204.17.5.0 - 11001100.00010001.00000101.00000000
255.255.255.224 - 11111111.11111111.11111111.11100000
--------------------------|sub|----

By extending the mask to be 255.255.255.224, you have taken three bits (indicated by "sub") from the original host portion of the address and used them to make subnets. With these three bits, it is possible to create eight subnets. With the remaining five host ID bits, each subnet can have up to 32 host addresses, 30 of which can actually be assigned to a device since host ids of all zeros or all ones are not allowed (it is very important to remember this). So, with this in mind, these subnets have been created.
204.17.5.0 255.255.255.224 host address range 1 to 30
204.17.5.32 255.255.255.224 host address range 33 to 62
204.17.5.64 255.255.255.224 host address range 65 to 94
204.17.5.96 255.255.255.224 host address range 97 to 126
204.17.5.128 255.255.255.224 host address range 129 to 158
204.17.5.160 255.255.255.224 host address range 161 to 190
204.17.5.192 255.255.255.224 host address range 193 to 222
204.17.5.224 255.255.255.224 host address range 225 to 254

Note: There are two ways to denote these masks. First, since you are using three bits more than the "natural" Class C mask, you can denote these addresses as having a 3-bit subnet mask. Or, secondly, the mask of 255.255.255.224 can also be denoted as /27 as there are 27 bits that are set in the mask. This second method is used with CIDR. With this method, one of these networks can be described with the notation prefix/length. For example, 204.17.5.32/27 denotes the network 204.17.5.32 255.255.255.224. When appropriate the prefix/length notation is used to denote the mask throughout the rest of this document.

The network subnetting scheme in this section allows for eight subnets, and the network might appear as:
Figure 2




Notice that each of the routers in Figure 2 is attached to four subnetworks, one subnetwork is common to both routers. Also, each router has an IP address for each subnetwork to which it is attached. Each subnetwork could potentially support up to 30 host addresses.

This brings up an interesting point. The more host bits you use for a subnet mask, the more subnets you have available. However, the more subnets available, the less host addresses available per subnet. For example, a Class C network of 204.17.5.0 and a mask of 255.255.255.224 (/27) allows you to have eight subnets, each with 32 host addresses (30 of which could be assigned to devices). If you use a mask of 255.255.255.240 (/28), the break down is:
204.17.5.0 - 11001100.00010001.00000101.00000000
255.255.255.240 - 11111111.11111111.11111111.11110000
--------------------------|sub |---

Since you now have four bits to make subnets with, you only have four bits left for host addresses. So in this case you can have up to 16 subnets, each of which can have up to 16 host addresses (14 of which can be assigned to devices).

Take a look at how a Class B network might be subnetted. If you have network 172.16.0.0 ,then you know that its natural mask is 255.255.0.0 or 172.16.0.0/16. Extending the mask to anything beyond 255.255.0.0 means you are subnetting. You can quickly see that you have the ability to create a lot more subnets than with the Class C network. If you use a mask of 255.255.248.0 (/21), how many subnets and hosts per subnet does this allow for?
172.16.0.0 - 10101100.00010000.00000000.00000000
255.255.248.0 - 11111111.11111111.11111000.00000000
-----------------| sub |-----------

You are using five bits from the original host bits for subnets. This allows you to have 32 subnets (25). After using the five bits for subnetting, you are left with 11 bits for host addresses. This allows each subnet so have 2048 host addresses (211), 2046 of which could be assigned to devices.

Note: In the past, there were limitations to the use of a subnet 0 (all subnet bits are set to zero) and all ones subnet (all subnet bits set to one). Some devices would not allow the use of these subnets. Cisco Systems devices allow the use of these subnets when theip subnet zero command is configured.
Examples
Sample Exercise 1

Now that you have an understanding of subnetting, put this knowledge to use. In this example, you are given two address / mask combinations, written with the prefix/length notation, which have been assigned to two devices. Your task is to determine if these devices are on the same subnet or different subnets. You can do this by using the address and mask of each device to determine to which subnet each address belongs.
DeviceA: 172.16.17.30/20
DeviceB: 172.16.28.15/20

Determining the Subnet for DeviceA:
172.16.17.30 - 10101100.00010000.00010001.00011110
255.255.240.0 - 11111111.11111111.11110000.00000000
-----------------| sub|------------
subnet = 10101100.00010000.00010000.00000000 = 172.16.16.0

Looking at the address bits that have a corresponding mask bit set to one, and setting all the other address bits to zero (this is equivalent to performing a logical "AND" between the mask and address), shows you to which subnet this address belongs. In this case, DeviceA belongs to subnet 172.16.16.0.

Determining the Subnet for DeviceB:
172.16.28.15 - 10101100.00010000.00011100.00001111
255.255.240.0 - 11111111.11111111.11110000.00000000
-----------------| sub|------------
subnet = 10101100.00010000.00010000.00000000 = 172.16.16.0

From these determinations, DeviceA and DeviceB have addresses that are part of the same subnet.
Sample Exercise 2

Given the Class C network of 204.15.5.0/24, subnet the network in order to create the network in Figure 3 with the host requirements shown.
Figure 3




Looking at the network shown in Figure 3, you can see that you are required to create five subnets. The largest subnet must support 28 host addresses. Is this possible with a Class C network? and if so, then how?

You can start by looking at the subnet requirement. In order to create the five needed subnets you would need to use three bits from the Class C host bits. Two bits would only allow you four subnets (22).

Since you need three subnet bits, that leaves you with five bits for the host portion of the address. How many hosts does this support? 25 = 32 (30 usable). This meets the requirement.

Therefore you have determined that it is possible to create this network with a Class C network. An example of how you might assign the subnetworks is:
netA: 204.15.5.0/27 host address range 1 to 30
netB: 204.15.5.32/27 host address range 33 to 62
netC: 204.15.5.64/27 host address range 65 to 94
netD: 204.15.5.96/27 host address range 97 to 126
netE: 204.15.5.128/27 host address range 129 to 158
VLSM Example

In all of the previous examples of subnetting, notice that the same subnet mask was applied for all the subnets. This means that each subnet has the same number of available host addresses. You can need this in some cases, but, in most cases, having the same subnet mask for all subnets ends up wasting address space. For example, in the Sample Exercise 2 section, a class C network was split into eight equal-size subnets; however, each subnet did not utilize all available host addresses, which results in wasted address space. Figure 4 illustrates this wasted address space.
Figure 4




Figure 4 illustrates that of the subnets that are being used, NetA, NetC, and NetD have a lot of unused host address space. It is possible that this was a deliberate design accounting for future growth, but in many cases this is just wasted address space due to the fact that the same subnet mask is being used for all the subnets.

Variable Length Subnet Masks (VLSM) allows you to use different masks for each subnet, thereby using address space efficiently.
VLSM Example

Given the same network and requirements as in Sample Exercise 2 develop a subnetting scheme with the use of VLSM, given:
netA: must support 14 hosts
netB: must support 28 hosts
netC: must support 2 hosts
netD: must support 7 hosts
netE: must support 28 host

Determine what mask allows the required number of hosts.
netA: requires a /28 (255.255.255.240) mask to support 14 hosts
netB: requires a /27 (255.255.255.224) mask to support 28 hosts
netC: requires a /30 (255.255.255.252) mask to support 2 hosts
netD*: requires a /28 (255.255.255.240) mask to support 7 hosts
netE: requires a /27 (255.255.255.224) mask to support 28 hosts

* a /29 (255.255.255.248) would only allow 6 usable host addresses
therefore netD requires a /28 mask.

The easiest way to assign the subnets is to assign the largest first. For example, you can assign in this manner:
netB: 204.15.5.0/27 host address range 1 to 30
netE: 204.15.5.32/27 host address range 33 to 62
netA: 204.15.5.64/28 host address range 65 to 78
netD: 204.15.5.80/28 host address range 81 to 94
netC: 204.15.5.96/30 host address range 97 to 98

This can be graphically represented as shown in Figure 5:
Figure 5




Figure 5 illustrates how using VLSM helped save more than half of the address space.
CIDR

Classless Interdomain Routing (CIDR) was introduced to improve both address space utilization and routing scalability in the Internet. It was needed because of the rapid growth of the Internet and growth of the IP routing tables held in the Internet routers.

CIDR moves way from the traditional IP classes (Class A, Class B, Class C, and so on). In CIDR , an IP network is represented by a prefix, which is an IP address and some indication of the length of the mask. Length means the number of left-most contiguous mask bits that are set to one. So network 172.16.0.0 255.255.0.0 can be represented as 172.16.0.0/16. CIDR also depicts a more hierarchical Internet architecture, where each domain takes its IP addresses from a higher level. This allows for the summarization of the domains to be done at the higher level. For example, if an ISP owns network 172.16.0.0/16, then the ISP can offer 172.16.1.0/24, 172.16.2.0/24, and so on to customers. Yet, when advertising to other providers, the ISP only needs to advertise 172.16.0.0/16.

For more information on CIDR, see RFC 1518 and RFC 1519 .
Appendix
Sample Config

Routers A and B are connected via serial interface.
Router A
hostname routera
!
ip routing
!
int e 0
ip address 172.16.50.1 255.255.255.0
!(subnet 50)
int e 1 ip address 172.16.55.1 255.255.255.0
!(subnet 55)
int t 0 ip address 172.16.60.1 255.255.255.0
!(subnet 60) int s 0
ip address 172.16.65.1 255.255.255.0 (subnet 65)
!S 0 connects to router B
router rip
network 172.16.0.0
Router B
hostname routerb
!
ip routing
!
int e 0
ip address 192.1.10.200 255.255.255.240
!(subnet 192)
int e 1
ip address 192.1.10.66 255.255.255.240
!(subnet 64)
int s 0
ip address 172.16.65.2 (same subnet as router A's s 0)
!Int s 0 connects to router A
router rip
network 192.1.10.0
network 172.16.0.0
Host/Subnet Quantities Table
Class B Effective Effective
# bits Mask Subnets Hosts
------- --------------- --------- ---------
1 255.255.128.0 2 32766
2 255.255.192.0 4 16382
3 255.255.224.0 8 8190
4 255.255.240.0 16 4094
5 255.255.248.0 32 2046
6 255.255.252.0 64 1022
7 255.255.254.0 128 510
8 255.255.255.0 256 254
9 255.255.255.128 512 126
10 255.255.255.192 1024 62
11 255.255.255.224 2048 30
12 255.255.255.240 4096 14
13 255.255.255.248 8192 6
14 255.255.255.252 16384 2

Class C Effective Effective
# bits Mask Subnets Hosts
------- --------------- --------- ---------
1 255.255.255.128 2 126
2 255.255.255.192 4 62
3 255.255.255.224 8 30
4 255.255.255.240 16 14
5 255.255.255.248 32 6
6 255.255.255.252 64 2


*Subnet all zeroes and all ones included. These
might not be supported on some legacy systems.
*Host all zeroes and all ones excluded.

vlsm exercises,vlsm examples,vlsm calculator,vlsm vs cidr,vlsm tutorial,vlsm addressing

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How to Root Samsung Galaxy Mini GT-S5570? Tutorial

 

Rooting Samsung Galaxy POP/Mini GT-S5570 is very simple you just have to follow this simple steps. And your phone will be rooted in 5 minutes.

Once you have rooted your device, you can install the Best Rom For Mini/Pop by reading this post  Which is the Best Rom for Galaxy POP/Mini GT-S5570?

Warning: Rooting your phone voids its warranty. And, this post will not work for phone with Baseband version is DDKC1 (see in Settings -> About Phone).

Before starting the root please make sure you have enough battery, about 60%

Step 1:

First download this file> ‘pop 2.3.6.zip‘

Step 2:

Copy the downloaded file to the root of your SD card. [You can copy it anywhere in the SD card but, it is easy to find it there]

Step 3:

Switch off your Phone.

Step 4: 

Press ‘Home + Power On‘ button at the same time until the phone starts in the Recovery Mode. (In recovery mode, the touch does not works, use Volume keys for up/down, Home key to select options & Power key for going back)

Step 5: 

In Recovery mode select ‘apply update from sdcard‘ from the Menu.

Step 6: 

Now select ‘pop 2.3.6.zip‘ from the SD card.

Step 7: 

Let the process complete.

Step 8: 

Select ‘reboot system now‘ option after the completion of setup

Step 9: 

After Reboot, check that ‘Superuser‘ application is installed or not. If yes, you successfully rooted your phone.
Congratulations!!! You have successfully rooted your Samsung Galaxy Pop/Mini gt-s5570

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android kit kat 4,4

Android KitKat 4.4

Smart, simple, and truly yours

Beautiful & Immersive

A more polished design, improved performance, and new features.

Just say “Ok Google”

You don’t need to touch the screen to get things done. When on your home screen* or in Google Now, just say “Ok Google” to launch voice search, send a text, get directions or even play a song.

A work of art

While listening to music on your device, or while projecting movies to Chromecast, you’ll see beautiful full-screen album and movie art when your device is locked. You can play, pause, or seek to a specific moment.

Immerse yourself

The book you're reading, the game you're playing, or the movie you're watching — now all of these take center stage with the new immersive mode, which automatically hides everything except what you really want to see. Just swipe the edge of the screen to bring back your status bar and navigation buttons.

Faster multitasking

Android 4.4 takes system performance to an all-time high by optimizing memory and improving your touchscreen so that it responds faster and more accurately than ever before. This means that you can listen to music while browsing the web, or race down the highway with the latest hit game, all without a hitch.

Smart & Simple

Google smarts improve every corner of the Android experience.

The future is calling

The new phone app automatically prioritizes your contacts based on the people you talk to the most. You can also search for nearby places and businesses, your contacts, or people in your Google Apps domain.

A smarter caller ID

Whenever you get a call from a phone number not in your contacts, your phone will look for matches from businesses with a local listing on Google Maps.

All your messages in the same place

Never miss a message, no matter how your friend sends it. With the new Hangouts app, all of your SMS and MMS messages are together in the same app, alongside your other conversations and video calls. And with the new Hangouts, you can even share your location and send animated GIFs.

Emoji everywhere

Sometimes words can’t express how you feel. For that, there’s Emoji, the colorful Japanese characters, now available on Google Keyboard.

Grab & Go

New features help you get things done while you’re on the move.

Print wherever, whenever

Now you can print photos, documents, and web pages from your phone or tablet. You can print to any printer connected to Google Cloud Print, to HP ePrint printers, and to other printers that have apps in the Google Play Store.

Pick a file, any file

From apps like Quickoffice, you can open and save files on Google Drive, other cloud storage services, or your device. And with quick access to recently used files, it's easier than ever to send the file you were just working on.

Your office, anywhere

Create and edit documents, spreadsheets and presentations from your phone or tablet with the newly redesigned Quickoffice

source ; http://www.android.com/versions/kit-kat-4-4/

Deal Finder

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How to Install Android on Your PC

It used to be the case that PC users had the choice of installing Windows or, if they were feeling adventurous, a version of Linux. This is still true, but it is now also possible to install OS X without owning a Mac and virtualization means that you can do all of this alongside your main operating system in a virtual computer.
This being Android.AppStorm, you may well wonder what virtualization has to do with your phone or tablet. Well, how would you feel about the chance of installing and running Android on your PC? Using a free copy of VirtualBox and the information in this guide, you can run a fully functioning – and legal – version of Jelly Bean on your computer.

It’s a Simple Process

First, you’ll need to grab yourself a copy of VirtualBox. This powerful virtualization utility can be used to install a second operating system alongside your primary one, and while this usually means running a second copy of Windows or trying out Ubuntu, there’s no reason why you shouldn’t be able install a mobile operating system as well.

Android may have been designed for your phone and tablet , but that doesn’t mean it needs to stay there.

Once you have the virtualization software up and running, you’ll need to get hold of a copy of Jelly Bean to install. This does not mean that you need to obtain an illicit copy of the operating system from an untrustworthy website, or rip a copy of your phone’s ROM – it is actually freely available.

Step 1: Grab an Android ROM

There are various versions of Android available for download, but it makes sense to work with the most recent version – Jelly Bean. Head over to the Android-x86 website scroll down to the Android-x86-4.2-devel section and click the View link for the most up to date version (at time of writing this is 4.2 20130228).

There are several Android ROMs available to download including the latest version of Jelly Bean.

Weighing in at just under 200MB, the download will take a moment to transfer. Once you have the ISO file on your hard drive, you’re ready to set about the task of installing it in VirtualBox.

Step 2: Going Virtual

Pay a visit to the VirtualBox download page and click the link to download the software. Here, I’m working with Windows 8, but VirtualBox is compatible with older versions of Microsoft’s operating system, and there are also versions available for OS X and Linux.

VirtualBox can be used to install a second operating system on your computer, including Android.

Once downloaded, run through the installation of the program  – just accept all of the default options. Don’t be concerned when you’re asked to install a new network adaptor as this is part if the usual installation process.

A virtual network adaptor will be installed by VirtualBox to allow virtual machines to get online.

Once installation is complete, launch VirtualBox and you’re ready to move to the next stage.

Step 3: Create a Virtual Machine

You’ll need to start by creating a new virtual machine onto which you will install Android. Click the New button. Name the virtual machine whatever you like, and (as Android is based on Linux) select  Linux from the first drop down menu. From the Version menu select Other Linux and then click Next.

Android is a Linux-based operating system and it needs to be correctly identified in VirtualBox.

Move the memory slider to the right so that 512MB or more of RAM is set aside for VirtualBox and click Next. Make sure that the Create a virtual hard drive now option is selected and click Create. Select VDI, click Next and then select the Fixed size option before clicking Next.
You can then use the slider to choose how large a disk should be assigned to the virtual machine, and you can use the folder button to choose where it should be stored. Click Create when you’ve configured your settings — it might take a few minutes for the virtual disk to be created.

Your virtual Android device can be assigned a drive capacity of your choice — go wild!

Step 4: Install Android

Make sure that you have your newly created virtual machine selected and then click the Settings button in the toolbar. Click the Storage link to the left hand side of the dialog and then towards the center click the Empty entry in the Storage Tree section.
To the right of this, click the small disc button and select Choose a virtual CD/DVD disk file from the menu that appears. Navigate to the ISO file you have downloaded, select it and click Open followed by OK.

The ISO files you’ve downloaded can be used as a virtual CD to install Android.

Power up your virtual machine by clicking the Start button in the VirtualBox toolbar.

If this is the first time you’ve used the program you may see a message letting you know about mouse capturing. When you move the mouse cursor inside the virtual machine window you’ll find that you cannot move it back out to control Windows as you normally would – just remember to press the right hand Ctrl key to free up the mouse when you need to.

Use the arrow keys on your keyboard to scroll down to the Installation option and press Enter.

Android can be run without installation, but opting to install provides a better, faster experience.

Now you will need to configure the virtual hard drive so that there is somewhere to install Android to. Select the Create/Modify Partition option and press Enter.
Select New at the bottom of the screen and press Enter, and then select the Primary option before pressing Enter again. Press Enter to create a partition that occupies your entire virtual drive.

Configuring hard drives for Android may seem complex, but it takes just a few moments.

Now select the Bootable option and press Enter, select Write and press Enter, and then type the word yes before pressing Enter once again. Select Quit, choose the partition you’ve just created and press Enter.
When prompted, select the option to use the ext3 file system and select Yes to confirm your choice. The GRUB bootloader takes care of launching Android, so select Yes to install it and then select Yes again to make the /system directory writeable.

The correct drive format must be selected for Android to work properly, so take care during configuration.

It won’t be long before Android boots, and at this point you should remove the virtual CD from the drive. Click the Devices menu and select CD/DVD Devices followed by Remove disk from virtual drive.

It’s a slightly time-consuming process, but getting Android on your PC is very rewarding.

Step 5: Almost There!

You might find that Android takes a little while to boot up — at least the first time around — and you’ll then have to run through the initial configuration just like you did the first time you switched on your phone or tablet.
Should you find that your mouse does not work and you are unable to click within Android, click the Machine menu in Virtual Box and then click Disable Mouse Integration. You may also find it useful to click View followed by Switch to Scale Mode if you find the mouse acts erratically — you can switch back to regular mode by pressing the right Ctrl key and C at the same time.

The first time you run Android you’ll have to set it up just like you did on your phone or tablet.

You can ignore any steps related to connecting to a wireless network as VirtualBox will just make use of your computer connection without the need for additional configuration.

Running Android within Windows can feel strange to start with, but it’s also great fun!

Now it’s time to pay a visit to Google Play and start downloading apps! Let us know how you get on, particularly if you think up any interesting uses for a virtualized copy of Android.

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installer Android 4 sur un ordinateur

 

How to install Ubuntu on MacBook using USB Stic

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Password Recovery Tips for Windows XP Users

Although Windows XP has been released for 10 years, many users out there have no idea about what to do when they forgot Windows XP password. The following is a list of Windows XP password recovery tips presented for those who still stick to the ten-year-old operating system.

Tip 1. Use Built-in administrator account

Premise: the built-in administrator account is not password protected.

1. Press Ctrl + Alt + Del twice on Windows XP logon screen.

2. Type "administrator" in the user name box and then click OK on the coming "Log On to Windows"
window.

3. Click Start, click Run box, and then enter "control userpasswords2", click OK.

4. On the classic user account window, select target user account and click "Reset Password" button.

Tip 2. Use Safe Mode

Premise: you can safe mode as administrator.

1. Turn on computer, press F8 to enter the Advanced Boot Options.

2. Select Safe Mode and then log in as administrator.

3. In Safe Mode, click Start and then select Run box.

4. Type "control userpasswords2", click OK.

5. On the Users interface, pick the user account, and then click Reset Password.

Tip 3. Use Command prompt

Premise: you can safe mode as administrator.

1. Repeatedly tap F8 key as the computer is booting.

2. Select "Safe Mode with Command Prompt" on Windows Advanced Options Menu and press Enter.
3. Enter password for your administrator account to get in safe mode. You'll see Windows command prompt
after entering safe mode.

4. Enter "net user" on the command prompt, and press Enter.

5. Enter "net user Jack 123456" on command prompt and press Enter. "Jack" refers to your target user
account name while "123456" refers to the new password to your target user account.


Tip 4: Use Password Reset Disk

Premise: You've created a password reset disk before your password is forgotten.

1. Insert your password reset disk into the computer.

2. Type a wrong password and press Enter.

3. A hint "use your password reset disk" will appear, click it.

4. Follow the steps in the Password Reset Wizard to reset the password.

Tip 5: Use system recovery options

Premise: A system repair disc or a Windows setup CD is required.

1. Start the computer from the system repair disc.

2. Choose your language settings, and then click Next.

3. Click Next to repair your computer.

4. After computer repair completes, select a recovery option and click Next to reset forgotten Windows password.

Tip 6: Use Rekeysoft Windows Password Recovery

Premise: Whenever you forgot Windows XP password, you can resort it to bypass the lost password.
With Rekeysoft Windows Password Recovery, you can easily crack Windows 7 password by creating a bootable CD/DVD or USB flash drive in 4 simple steps without data loss.

1. Download and install Rekeysoft Windows Password Recovery.

2. Create a bootable password reset disk with CD/DVD or USB flash drive.

3. Boot the computer from the CD/DVD or USB flash drive.

4. Crack Windows XP password by following the instructions.

If you forgot Windows XP password, you could do Windows XP password recovery with these tips.

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All About CCNA Certification

CCNA is a popular and well recognized networking certification in the industry. The CCNA is the composite exam associated with the Cisco Certified Network Associate certification. This exam tests a candidate's knowledge and skills required to install, operate, and troubleshoot a small to medium size enterprise branch network.

How to Attain the CCNA Certification? 

Which Path to Follow This is a very common question among candidates who are pretty new to this area and would like to attain the CCNA certification. It's to be remembered that there are two ways to attain the CCNA certification which is presented below:

A. One Exam Path

Take the 640-802 CCNA composite exam associated with the Cisco Certified Network Associate
 certification

B. Two Exam Path

Take the 640-822 Interconnecting Cisco Networking Devices Part 1 (ICND1) v1.0 exam Take the 640-816 Interconnecting Cisco Networking Devices Part 2 (ICND2) v1.0 exam

Advantages and disadvantages of following any one path

If you follow the Two Exam Path - You become a CCENT by passing the ICND1 Exam and then a CCNA by passing the ICND2 exam. If you follow the One Exam Path - You become a CCNA by passing the CCNA composite exam. You do not earn the CCENT certification.

If you are new to the field of networking you should go for two exam path as this gets you started from basics and plus you get to ear the CCENT as well. If you already have some experience in the field of networking you can go for the One exam path as this will help you earn your CCNA certification in one go. Hence, based on your personal circumstances it's up to you to decide which path to opt for.

How to Prepare for CCNA Exam? 

Preparing for the CCNA exam is not an easy task and just like anything else in this world requires time, effort, patience and hardwork. It's best to familiarize yourself with the CCNA Syllabus before preparing for your CCNA exam as this gives you a fair idea of what you're getting into... to get you mentally prepared. In my opinion, the starting point of being successful in any area of your life is first accept mentally that you are going to find things difficult when you do them for the first time and if you do it over and over again, you will find better ways of doing it and eventually improve. Hence, derive the right kind of motivation and attitude before beginning your preparation for the CCNA exam.

What are the kind of questions in a CCNA Exam? 

The following are the kind of questions that appear in a CCNA exam:
Multiple-choice single answer
Multiple-choice multiple answer
Drag-and-drop
Fill-in-the-blank
Testlet
Simlet
Simulations
CCNA Bootcamp or CCNA Online Training?
CCNA Online Training?

You should opt for CCNA online training if you're super busy and like to take things at your own pace. However, one area which needs to be concerned is motivation. Since, you're studying and practicing all alone - you should make sure to have the right kind of attitude before opting for a CCNA online training.
An online training course is completely online allowing you to study when you want- 24 hours a day, 7 days a week, 365 days a year from home, the office, or an Internet cafe - the only prerequisite being access to an internet connection

CCNA Bootcamp? 

A CCNA bootcamp is typically a week long classroom training which are taken by experts in the field of networking. The biggest advantage that this format of training has is that, the experts condense the entire CCNA syllabus with the right kind of environment. You're given hands on experience on routers, switches and other networking devices to help you get industry ready.

Hopefully the above guide will help you clear the CCNA exam successfully! All the Best!

Chris Ryan is a certification enthusiast and loves to write on various IT certifications. You should check him out the blog where you can learn about the CCNA Salary [http://itcertificationsyllabus.com/ccna-salary.html].

Article Source: http://EzineArticles.com/?expert=Chris_M_Ryan


 

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Basic Router Configuration - Cisco

http://hulkload.com/wa9kky6rbtpd

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The Best Messaging Apps for Your Android

The advent of smartphones and tablets has revolutionized the way we keep in touch with our social circles. The days are long gone when messaging meant web chats through specific IM applications on personal computers or costly SMS over the cell phone network. The new generation messaging apps use the Internet connectivity to transmit messages from the mobile devices, which virtually makes it a free-service with the added benefit of being accessible even on the go. Here are some of the most popular apps on the Android platform for messaging:

a. Whatsapp: Founded in 2009, this Android app has more than 400 million users in the world. The premise of this application's operation is simple: it uses the phone number associated with your Android device to uniquely identify you on its network. Then, it scans your contact list and provides a list of all users who are signed up with Whatsapp. Apart from text messages, users can also send images, videos and audio messages through the Internet. The latest statistics indicate that this messaging service handles over ten billion messages through its system every day. The best thing about Whatsapp is that it is still a free service in the Android ecosystem and do not host any advertisements as well.

b. Google Hangouts: Hangouts was first introduced as a video-conferencing tool with a tight integration with its Google's social network, Google+. However, over the last couple of years, Google Talk and Voice applications have been merged with Hangouts, which now serve as its unified messaging app. The Android app is designed to work efficiently with both smartphones and tablets, and can seamlessly switch between the simple text-mode to high-resolution video-chatting.

c. WeChat: It is one of the many Asian organizations that have revolutionized the messaging industry. Its USP lies in the fact that it supports a wide range of languages, thereby making it popular among several non-English speaking Android users. Apart from text-based messaging, WeChat also supports voice messages, group conferences, social network plugins and many more.

d. Facebook Messenger: Facebook had a simple messaging tool for its users to send private messages to specific people on their network. However, with the rising popularity of the messaging tool, Facebook decided to launch it as a separate app on Android, which laid the foundation for Facebook Messenger. This app can be used to chat with your Facebook friends, and integrates extremely well with the web and mobile app versions of the original social networking site.

Messaging apps work extremely well on smartphones like GT-I9300 and GT-I9500 S4. These smartphones can be purchased online from trusted web stores.

Article Source: http://EzineArticles.com/?expert=Shelia_Z_Smithson

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