What is Information Security?
Information security is a process of protecting information and information systems from unauthorized access.

What are Virus, Worm, Trojan horse and Spyware?
● A virus attaches itself to a file so it can spread from one system to another & leaving infections as it travels.
● A worm is most likely to a virus by its design. Worms spread from PC to PC, but unlike a virus, it has the capability to travel without any help from a person.
● A Trojan horse is similar to a worm but it has the ability to create a backdoor, through which a victim can be controlled by the attacker.
● A Spyware is more advanced than a Trojan horse. After entering to the victims system it try to takes the administrative power of victims system.

What is Ethical Hacking?
Ethical Hacking is authorized use of computer and network resources using hacking techniques.

Type of Ethical Hacking:
● White Box: When you have Full knowledge & information about the system, which makes it easy for anyone to learn about the various details and then fingerprint that very system.
● Vulnerability Assessment: Typically done by using some tool. The only negative is that your testing will be as good as your tool. Example: Nessus, GFI LANGuard.
● Penetration Testing: Complete review of vulnerabilities, how to use those vulnerabilities and considerate how networks respond to them. Example: Nessus.
● Black Box: When you have no knowledge about the system infrastructure. As an Ethical hacker, this should be the one that can help you see things from a hacker’s point of view as you like the hacker doesn't have any primary knowledge about the system.

Steps of Hacking:
● Footprinting:

Gathering information about a target system using publicly available sources. Tools: Fping, Nmap, Nslookup, Whois lookup.

● Scanning:

Gathering information about network services on a target system.
Tools: Telnet, Netcat, Strobe, Pscan, and SATAN.

● Enumeration:

Gathering information about user accounts and applications on a target system. Tools: Netcat, Rcpdump, Dumpsec, Getmac.

● Gaining access:

Compromising the security of a target system by cracking passwords, exploiting buffer overflows, or some other technique.

● Elevating privileges:

Gaining increased control of a target system by elevating the rights of a cracked account. Tools: Lsadump2, LC3, Pwdump2, and John the Ripper.

● Installing backdoors:

Creating hidden mechanisms to allow attackers to reenter a compromised system at will

● Covering tracks:

Erasing log files and other evidence of intrusion.

Types of Attacks:
● Access Attack:

The trespasser tries to gain entrance to resources on your network by exploiting flaws in software such as buffer overflows and information outflow and by uplifting the intruder’s rights to execute random code.

Type of Access Attack

• Cross Site Scripting
• Man In The Middle
• War Dialer

● DOS Attack:

A type of attack that tries to stop valid users from accessing network services. In a denial of service the attacker tries to stop access to a system or network by some possible resources, including the following:

1. Flooding the network with so much traffic that traffic from legal clients is snowed under.
2. Flooding the network with so many requests for a network service that the host given that the service cannot accept similar requests from rightful clients.
3. Disturbing connections between hosts and rightful clients by a range of means, including modification of system configuration information or even physical demolition of network servers and works.

Type of DoS Attack

1. Smurf Attack
2. SYN Flood
3. Ping of Death
4. Land Attack
5. Tear Drop Attack
6. DDoS Attack
7. Buffer Overflow

● Reconnaissance Attack:

• The trespasser tries to plot your network services in order to exploit vulnerabilities detected.
• Reconnaissance is a term at times used to illustrate behavior more commonly known as footprinting, the method of gathering as much information as possible about the network from openly existing sources, and enumeration, unlike methods used for gathering information that reveals weakly sheltered network resources that can be exploited for breach into net-works.

● Active Attack:

● Passive Attack: