Page 75 - 2501_KVS_C-7

Aryan: Then how does it work?

Gowri: There are several types of firewall techniques that will prevent
potentially harmful information from getting through:

1. Packet Filter: It looks at each packet entering or leaving the network and
accepts or rejects it based on user-defined rules.

2. Application Gateway: It applies security mechanisms to specific applications, such as FTP and
Telnet servers. This is very effective, but can degrade performance.

3. Circuit-level Gateway: It Applies security mechanisms when a connection
is established (TCP or UDP). After the setup of connection, packets can flow
between the hosts without further checking.

4. Proxy Server: It intercepts all messages entering and leaving the network,
and the server effectively hides the true network addresses.

Aryan: Thank you friend for such an elaborate discussion about firewall. Now I want to know
something about Cybercrime.

7.5 CYBERCRIME AND COMPUTER ETHICS

Gowri: Okay, first I will tell you what Cybercrime actually is:

Cybercrime is defined as the crime that is facilitated by the use of electronic gadgets such as
computer, smartphone etc. involving communication or information systems through internet.

In simple terms, we can also say that Cybercrime is a criminal activity that either targets or uses
a computer, a computer network or a networked device.
Cybercrime is carried out by individual or organisation(s). These types of crimes are committed
daily on the internet.

Aryan: Oh…, What are different types of cybercrimes?

Gowri: Let us discuss some common cybercrimes:
1. Cyber Bullying: Cyberbullying includes sending, posting, or sharing negative,
harmful, false, or mean content about someone else through social media, email,
instant messaging, etc.

2. Identity theft: Criminals often steal other's identity information, such as credit card details,
addresses, email addresses, and more. Using this information, they can pretend to be someone else
and even create new bank accounts, etc.
3. Ransomware: Ransomware enters your computer network and encrypts files, meaning you no
longer have access to them. The attacker then sends a notification demanding a large sum of money
to restore your data.
4. Email Bombing: An email bomb is another form of internet abuse. Email bombing involves
overloading a single email address with a large volume of messages, which can cause the recipient’s
email server to slow down or even crash.

Computer Security 73