The Internet began to use in 1960. In the beginning time, it was not an issue to deal with cyber crimes as it is not accessible to the public. Only the defense systems of a country and the top officials of a country uses the privilege of the internet and the scenario was smooth and good.
In the late 1990s, the internet was more developed and it was the beginning that the public was given access to the internet and the internet started to spread its wings in the public. In every good, there will be a hidden bad thing inside it. The Internet was not different from that as the criminals started using the internet to steal others' personal and sensitive data and even destroy a system in a network. It varies from simple adware to complex viruses that are able to destroy a system and steal all its data.
At the beginning of the 2000’s the cybercrime rate increased and every country‘s law enforcement started to deal with cybercriminals. Packet tracing and packet tampering and stealing data using middle man attacks and much more complex threats come into the picture. The focus of cybercrime definition changes from destroying a computer to destroying or manipulating or stealing data in a computer or from a network.
Now cyber crimes are increasing and it is expected that millions of people are getting impacted by cybercrimes every day around the globe. So we classify the cybercriminals as inside or outside criminals for an organization.
An insider attack can be defined as an attack that is performed by an authorized person in that organization. Mostly this happens from an employee who has a criminal mind or is highly dissatisfied in the organization who has all the authorization to access all the networks of that organization.
The inside attack is an easy process for the attacker and it can make a high impact on the network or the system as the attacker knows about the network and its security and its easy to make a huge impact from the attacker to make the network crash. Installing intrusion detection internally is the only way to reduce the internal attack.
It can be defined as an attack from an outsider with or without the help of an insider of the organization. This attack can be fatal as it not only causes financial loss and loss of sensitive information, also the loss of the organization's reputation and trust.
An external attacker will be monitoring the network for some days before the attack to get much information so the only chance to block him is to make a strong firewall and gateway and also hire a network professional and if needed ask the help of an ethical hacker to respond to the attack.
Another classification in cyber crimes as structured and unstructured attacks that is classified according to the level of knowledge of the hacker or the level of impact of the attack. It can be simple to fatal depending on the attacker's skill and experience.
These types of attacks are done by amateurs who don’t have any skill or experience in the field of networks. it has only a negligible impact on the network. the major reasons behind such attacks may be fun or trying a new hack tool or trying to get some money or to impress someone.
These types of attacks can be fatal and make much loss for the organization because it is done by professional hackers who have much skills and experience in network security and its layers. They have a well-defined aim and have perfect skills and tools to open the firewall and network security. They can able to mask intrusion detection and such criminals are dangerous mostly by some rival country or from terrorist groups, etc.
Now in this modern world cyber crimes are becoming a low-cost investment and secret method to make a high income. So Understand about cyber security and making precautions for cyber crimes are almost all country's responsibility, even every individual must know about basic cyber security to protect themselves.