Each computer connected to the Internet has its own unique network address - IP. Two computers with the same ip cannot be on the network at the same time. Sometimes the user needs to determine the address of some Internet resource or find out his own.
If you know the domain name of the resource, you can determine its address using the ping command. For example, let's define the ip of a Google search service. Open Command Prompt: Start - All Programs - Accessories - Command Prompt. Type "ping www.google.com" (without quotes) and press Enter. The line "Exchange packages with www.google.com" will appear, then the ip of this resource will be indicated in brackets.
Sometimes the user suspects that someone has connected to his computer. In this case, you can find out the ip-address of the remote computer using the netstat –aon command. Open Command Prompt again, type "netstat - aon", press Enter. You will see a list of connections. In the column "External address" will be indicated the ip of remote computers.
Pay attention to the "Status" column. The "ESTABLISHED" value indicates that a connection is currently established with the ip-address specified in the "External address" column. The LISTENING state indicates that some program on your computer is waiting for a connection. You can see the port number opened by this program in the "Local address" column.
When you see an open port on your computer, check which program is opening it. It is possible that the server side of the Trojan horse is present on your computer, waiting for a connection. Some ports, such as 135 and 445, are opened by the operating system. It is recommended to close them using the wwdc.exe program.
Sometimes it becomes necessary to determine the ip of the sender of the letter. This can be done in two ways: the first is through mail programs, for example, Outlook Express or The Bat !. View the header of the letter by selecting the appropriate option in the program menu, the header will contain all the information, including the sender's address.
The second way to find out the sender's ip address is to use the corresponding services of the mail service you are using. For example, in Rambler to view the header, open the letter, then click the "More Actions" button and select "Letter Headers". There are similar services in other postal services.