Note: I am assuming that you have at least some knowledge about TCP\IP.
What is all the hype about socket programming? What exactly are sockets?
TCP\IP or Transmission Control Protocol\ Internet Protocol is the language or the protocol used by computers to communicate with each other over the Internet. Say a computer whose IP address is 99.99.99.99
wants to
communicate with
another machine whose IP address is 98.98.98.98 then would will happen?
The machine whose IP is 99.99.99.99 sends a packet addressed to another
machine
whose IP is
98.98.98.98. When 98.98.98.98 receives the packet then it verifies that it
got
the message by sending a
signal back to 99.99.99.99.
But say the person who is using 99.99.99.99 wants to have simunateously more
than one connections to
98.98.98.98.....then what will happen? Say 99.99.99.99 wants to connect to
the
FTP daemon and download
a file by FTP and at the same time it wants to conect to 98.98.98.98's
website
i.e. connect to HTTP daemon.
Then 98.98.98.98. will have 2 connects with 99.99.99.99 simountaneously.Now
how
can 98.98.98.98.
distinguish between the two connections...how does 98.98.98.98. know which
is
for the FTP daemon and
which for the HTTP daemon? If there was no way to distinguish between the
two
connections then they
would both get mixed up and there would be a lot of chaos with the message
meant
for the HTTP daemon
going to the FTP daemon. To avoid such confusion we have ports. At each
port a
particular service or
daemon is running by default. So now that the 99.99.99.99 computers knows
which
port to connect to, to
download a FTP file and which port to connect to, to download the web page,
it
will communicate with the
98.98.98.98 machine using what is known as the socket pair which is a
combination of an IP address and a
Port. So in the above case the message which is meant for the FTP daemon
will be
addressed to
98.98.98.98 : 21 (Notice the colon and the default FTP port suceeding it.).
So
that the receiving machine i.e.
98.98.98.98 will know for which service this message is meant for and to
which
port it should be directed to.
In TCP\IP or over the Internet all communication is done using the Socket
pair
i.e. the combination of the IP
address and the port.
DOS Hacking utilities shipping with Windows and Linux Utilities too
Most Hacker Friendly utilities that ship with Windoze are hidden and a
normal
user will not be able to find
them.All of them are either in the c:\windows directory or are in the
Windows
Installation CD.
PING
Now lets start with what exactly Ping is. Now Ping is a part of the ICMP
protocol i.e the Internet Control
Message Protocol. ICMP is a protocol used to troubleshoot TCP\IP networks.
Ping
is a command which
sends out a datagram to the specified host. This specified host if alive
i.e.
turned on sends out a reply or
echos off the same Datagram. If the datagram that reaches back to your
computer
has the same datagram
that was sent then it means that the host is alive. So Ping is basically a
command which allows you to check
if a host is alive or not. It can also be used to calculate the amount of
time
taken for a datagram to reach the
host. It is so deadly that it can be used to ping a hostname perpetually
which
may even cause the host to
crash. Now what happens is that when a host receives a Ping signal, it
allocates
some of it's resources to
attend to or to echo back the datagram. Now if you Ping a host perpetually,
then
a time will come when all
resources of the host are used and the host either hangs or restarts.
Due to Ping's deadly nature, most shell account ISP's hide the Ping utility.
To
find it issue the folowing
command:
whereis ping
It is usually hidden in /usr/etc
Ping has many parameters and a list of parameters can be found by reading
the
man pages or if you are
running Windows you can get help by simply typing ping at the DOS prompt.
The flood ping which pings a host perpetually is:
ping -f hostname
ping -a hostname can be used to resolve addresses to hostnames.
When I typed ping at the dos prompt I go the following help:
There are many new Internet Service Providers which give absolutely free Internet access, of course you do need to pay for the telephone bill. These free ISP's make money by the advertisements that they display in the form of a banner which covers a part of your screen each time you connect to the Internet.
Well, these banners are quite a nuisance as they clog bandwidth and slow down our Internet Connection. The advertisements displayed by them, share your modem to load. Wanna learn how to remove this bar and still access the net for free? Well read on.
The answer to this hack lies in some kewl files called Dynamic Link Libraries. First lets see what .dll files are used for. Dynamic Link Libraries is basically a collection of commands or data which control how a program looks. Take the example of Microsoft Office. Now whenever you launch it, the main .exe file reads the .dll file associated with it and accordingly displays the toolbars.[NOTE: Almost all Windows applications use the same .dll file to display say the Title Bar]. So basically we can conclude that .dll files are most commonly used to change the way applications look.
Now the good thing about Dynamic Libraries is that they can be loaded or unloaded when a particular program has stopped using it. This is done to save resources or memory. They can also be shared at the same time by various applications.
Now before we go on to the hack let's learn how these free ISP's work.
When you click on the Connect button, the Modem dials into the FREE ISP and tries to connect. Before the connection is fully established, the FREE ISP software checks to see if the .dll file associated with exists or not. If yes, then it connects and a banner pops up. On the other hand, if the .dll file does not exist then the FREE ISP Software refuses to connect. So what you need to do in order to surf for free without the irritating Banner ads, first connect to the FREE ISP's server, and once the connection has been established (screeching sound stops), delete the .dll file associated with it. It is that simple. The only thing you need to know is which .dll file to delete.
To find out the .dll files associated with your FREE ISP Software, install the software on a clean machine (where the same software has not been installed earlier). Then using the FIND tool (START >Find) locate all Dynamic Link Libraries (*.dll)which have been created or modifies during the last one day(Under the Date Modified Tab). This will be foolproof only if no other software has been installed during the last 24 hours.
Ankit Fadia
ankit@bol.net.in
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