Passive Port Scanner

This app based port scanner will test whether common ports are open on a server. Useful in determining if a specific service (e.g. HTTP) is up or down on a specific server.

Ports scanned are: 21, 22, 23, 25, 80, 110, 139, 143, 445, 1433, 1521, 3306 and 3389

================================

Network ports are the communication endpoints for a machine that is connected to the Internet. When a service listens on a port it can receive data from a client application, process it and communicate a response.

Malicious client applications (ex. scripts, bots, malware) often exploit code found in the server software that let them get unauthorized access on the remote machine. This is one of the reasons why testing all ports is vital to achieving an in-depth security verification.

Port scanning is part of the first phase of a penetration test and allows you to find all network entry points available on a target system. The port scan techniques are different for TCP and UDP ports, that is why we have dedicated tools for each one.

port scanner is an application designed to probe a server or host for open ports. Such an application may be used by administrators to verify security policies of their networks and by attackers to identify network services running on a host and exploit vulnerabilities.

A port scan or portscan is a process that sends client requests to a range of server port addresses on a host, with the goal of finding an active port; this is not a nefarious process in and of itself.The majority of uses of a port scan are not attacks, but rather simple probes to determine services available on a remote machine.

To portsweep is to scan multiple hosts for a specific listening port. The latter is typically used to search for a specific service, for example, an SQL-based computer worm may portsweep looking for hosts listening on TCP port 1433.

Why should I use an Online Port Scanner?

The main advantage of using an online version/ of the Nmap port scanner versus using it on your local machine is that it gives you an external view of your systems as they are seen by any hacker from the Internet. If you do the same scan from your internal network you may obtain different results because of various firewalls and network restrictions.