IP Addressing

IP address is the way by which a system is identified on a network. System may include your desktops, laptops, mobile phones, and even household items such as refrigerator and cars which connects to a network. A network can be a local LAN, WAN or even public networks such as the internet.

Most of the IP addresses assigned today are version 4 or IPv4. However there is a move towards shifting into version 6 or IPv6. The major cause of this is the depletion of IPv4 addresses and the need for a larger set of addresses to accommodate the increasing size of the internet. Here I’ll discuss IPv4 addresses in detail and how they are used today

What is an IP address?

IP address is a 32 bit string which can uniquely identify any device on a network. When represented in binary it would look something like.

11000000101010000000000100000001

Since there are 32 binary bits, the total number of address combinations possible is 2^32 (with a few exceptions) which is indeed a very large number.

From the binary representation it can be seen that this format is not too human friendly, though machines find it most effective to use the binary format. Hence the representation above is modified a little, by grouping together 8 bits or 1 byte at a time. This group of 8 bits is commonly referred to as an octet. The decimal form of each octet is calculated to generate a human readable form.

11000000 = 192
10101000 = 168
00000001 = 1
00000001 = 1

Thus the above address becomes

19216811

Well that’s easier to read. However we need a way of distinguishing between each octet while reading it. Hence a dot (.) is introduced between each octet to represent the address as shown below

192.168.1.1

This representation is called the dotted decimal format since it represents the addresses as decimal numbers with dots in between each octet. This is the most popular way of representing IPv4 addresses.

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Multiple instances of gtalk

Have you ever tried logging into yahoo messenger from two clients on the same machine? Forget different ids... It does not even let you have two login instances with the same id.

Have you ever tried logging into gtalk from two clients on the same machine? Have you been able to at least start two instances of gtalk on your PC?

Look no further. For gtalk can be tweaked not only to run more than one instance of it , but you can actually login into them using different gmail ids.

Now why on the earth would someone want to do that? Well if for any chance that you maintain different ids for different purposes. Like one for your work, other for your family or girlfriend etc.

The tweak is simple. The first step is to create a shortcut to gtalk on your desktop. If you already have this, forget this step.

Next, right click on this shortcut, select properties, and choose the tab called Shortcut. You can see a field called ‘Target’ which is where our tweak will be inserted. At the end of this field, to the already existing text add the text as shown below.

/nomutex

Make sure that it is added right after the

……\googletalk.exe"

If any other text is present here, then delete it. So the final text in the target field will read

…………………… Google Talk\googletalk.exe" /nomutex

Click OK to save the propertied.

Done!!!!!!!!!!

Now every time you click this icon on your desktop, a new instance of gtalk will pop up. You can sign in with your different ids into each instance.

Enjoy!!!!!!!!!!!!!

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