Port scanning

PORT  SCANNING

Concept:

In a computer system there are 65535 ports which are used for data packets,information receiving and sending throught the network and internaly in our system.Basically,some ports are hardwired such as electric ports.But some ports are part of network and each port has it`s own functioning.A port get opens when data go through that port or port is being used.

A process called network port scanning detects test messages at each port number individually to identify which ports are open. Network professionals use port scanning as a tool to measure their exposure to attackers and often lock down their networks by closing non-essential ports. Hackers, in turn, use port scanners to probe networks for open ports that may be exploitable.         

There are many software and applications which are used for port scaning to find how many ports are open and port is related to which model such as tcp or udp.

Demonstration:

There are some tools which scans a particular ip address or domain name and find the open ports, vulnerbilities.

                    Here i will give demonstration on Nmap which is a best tool for port scaning.

Steps:

1. Open Nmap tool

2. Enter your target Ip address or domain name is target box.

3. slect the type of scan from profile box such as intense scan, tcp scan or udp scan etc.

4. click on scan button.

it will take some time according to your scan type and it will show the result of scan about ports,version of os,host detail etc.

Tools:

·       Nmap

·       Angry IP Scanner

·       Superscan

·       Autoscan-network

·       Unicornscan for linux

·       Netstat command in windows

Resources:

·       https://nmap.org/ nmap official website

·      https://www.lifewire.com/port-numbers-on-computer-networks-817939  definition of port scanning

·       https://www.youtube.com/watch?v=uNTsURvslvc nmap tutorial

·       https://www.youtube.com/watch?v=6Axj2PSMx34                    netstat command for port scaning

·       https://www.youtube.com/watch?v=w5mif1JdGTA unicornscan in kali linux tutorial