To the exchange of data occurred successfully, it is necessary that the appropriate ports at the nodes are open, i.e. can receive and transmit data. The process of finding open ports is called a scan. Do it and hackers, and system administrators: the first one to introduce malware on another computer, the second is to prevent the first to do it. Check the ports you can on your computer by installing a special program – scan the ports or by using online scanners. Go to the website
If your computer has a firewall with attack detection and auto-blocking an attacking host, disable this option or add a in the exception list, otherwise the scanner is blocked. In the section "scan Settings" enter the numbers of the first and final port of the range you want to check. It can be so-called reserved rooms from 1 to 1023, or all ports on your computer.
It is important to set the time during which the scanner will wait for a response from the port. If a "Timeout connection" (this option) to make too small, the port may not respond and will be incorrectly detected as closed. On the other hand, too much waiting time will significantly slow down the test. It is better to adopt the recommended value is 0.3 sec.
"Host address" and "host Name" is your IP address, which service determines automatically. If the address is not specified, scanning will not start. Click "OK" to start scanning. This will open a new window that displays the progress.
After searching, the result will be displayed:- date and time of the inspection;
- address of the host;
numbers checked ports;
- the number of open and closed ports;
- duration of the scanning.In addition, the service will give recommendations on how to identify the process which uses the open ports.
You can run a scan from your computer. Download the program "port Scanner v2.1"
In the section "Scan ports" enter in the boxes the start and end port numbers from the range that will be checked. If the computer is not in network, enter its IP address is not necessary. Ask in the appropriate section of the scan rate. It is determined by the response time of the port. It is better to choose the average speed, so, on the one hand, to avoid errors in the determination of the status of the port, and with another – not too tighten the verification process. Check the box "Output port information" to see the search result. The scanner finds open ports and determines the processes that use them.