Broadly speaking, both Hacking and Ethical Hacking refers to break-in the network or check for the vulnerabilities of a website. Hacking is illegal and rewards you with sentences that ranges from months to lifetime, whereas Ethical Hacking is an entirely legal and professional work which showers you with recognition and promotions in the security domain.

Scanning may be referred to as a set of procedures for identifying hosts, ports and the services attached to a network. Scanning is a critical component for information gathering. It allows the hacker to create a profile on the site of the organization to be hacked. Types of scanning include:

• Port scanning
• Vulnerability scanning
• Network scanning

Footprinting refers to accumulating and uncovering information about the target network before attempting to gain access. Hacking techniques include: 

• Open source footprinting: This technique will search for administrator contact information, which can be later used for guessing the correct password in social engineering.
• Network enumeration: This is when the hacker attempts to identify the domain names and network blocks of the targeted
• Scanning: Once the network is known, the second step is to pry on the active IP addresses on the network.
• Stack fingerprinting: This techinique should be the final footprinting step that takes place once the port and host are mapped.

Network sniffing involves using sniffer tools that enable real-time monitoring and analysis of data packets flowing over computer networks. Sniffers can be used for different purposes, whether it’s to steal information or manage networks.

Network sniffing is used for ethical as well as unethical purposes. Network administrators use these as network monitoring and analysis tools to diagnose and prevent network-related problems such as traffic bottlenecks. Cybercriminals use these tools for dishonest purposes such as identity usurpation, email, sensitive data hijacking and more.

Cross-site scripting (XSS) attacks are a type of injection where malicious scripts are injected into otherwise benign and trusted websites. XSS takes place when an attacker inserts a malicious payload, usually in the form of JavaScript code in a web form. XSS vulnerabilities are categorized as follows:

• Reflected cross-site scripting
• Stored cross-site scripting
• DOM-based cross-site scripting

ARP poisoning is a form of network attack that can be mitigated through the following methods:

• Use packet filtering: Packet filters can filter out and block packets with conflicting source address information.
• Avoid trust relationship: Organizations should develop a protocol that relies on trust relationship as little as possible.
• Use ARP spoofing detection software: Some programs inspect and certify data before it is transmitted and blocks data that is spoofed.
• Use cryptographic network protocols: ARP spoofing attacks can be mitigated by the use of secure protocols such as SSH, TLS and HTTPS which send data encrypted before transmission and after reception.