The presentation discusses network security, which consists of policies and practices to prevent unauthorized access to computer networks and resources. It highlights the increasing threat of cyberattacks, particularly in sectors like financial services and utilities, emphasizing the necessity for robust cybersecurity measures, including authentication and cryptography. The document also compares symmetric and asymmetric cryptography, detailing how each method secures data transmission.

1. Network
Security
Group Presentation By:
• Eshrak Ur Rahman
• Md Tuhin
• Nasib Muhammad Arif

2. ABOUT
Network Security
Network security consists of the policies and practices
adopted to prevent and monitor unauthorized access,
misuse, modification, or denial of a computer
network and network-accessible resources.
Only Network security can protect you from trojan horse
viruses. Network security involves the authorization of access
to data in a network, which is controlled by the network
administrator. Users choose or are assigned an ID and
password or other authenticating information that allows
them access to information and programs within their
authority. Network security covers a variety of computer
networks, both public and private, that are used in everyday
jobs; conducting transactions and communications among
businesses, government agencies and individuals. Networks
can be private, such as within a company, and others which
might be open to public access. Network security is involved
in organizations, enterprises, and other types of institutions
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3. Cyber Attack
A cyberattack is any type of offensive maneuver
that targets computer information systems,
infrastructures, computer networks, or personal
computer devices
Attacks Per
Day
BILLION
Cost of
Cybercrime
in 2017
Percentage
increase
in cost of
Cyber
security
in a year
Since the late 1980s cyber attacks have evolved several times to use
innovations in information technology as vectors for committing cybercrimes.
In recent years, the scale and robustness of cyber attacks has increased rapidly,
as observed by the World Economic Forum in its 2018 report: "Offensive cyber
capabilities are developing more rapidly than our ability to deal with hostile
incidents.
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4. Average cost of cyber
crime for five countries
Key Metrics
Average Cost($) Increase
USA 21.22m 22.2%
Germany 11.15m 42.4%
Japan 10.45m 24.6%
UK 8.74m 21.2%
France 7.90m 00.0%
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5. Financial services
The number of cyber attacks against
financial services companies reported to the
Financial Conduct Authority (FCA) has risen
by more than 80% in the last year
Utilities and energy
One of the most feared attack surfaces is
a nation’s power grid, and for good
reason. If cyber war erupts and a nation’s
power grid is hacked, everything that
keeps a society afloat could essentially
crumble
Aerospace and
defenseThe aerospace and defense sectors face
cyber threats from advanced persistent
threat (apt) groups
Technology and
softwareMany high-tech organizations have open
environments and corporate cultures that
are designed to stimulate creativity and
collaboration, but are more difficult to
defend. As a result, high-tech organizations
typically have a very large attack surface to
protect.
Most affected
Industry
• Financial services
• Utilities and energy
• Aerospace and
defense
• Technology and
software
5
Average annualized cost by industry sector US$
millions
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6. SOLUTION
o Protect vital information (data) while still allowing access to
those who need it Ex: Financial, Trade secrets, educational,
medical records, etc.
o Provide authentication and access control for resources
o Safe transmission of information
o Safe commercial files or data (Music Video, Album etc)
o Overall, network security measures are needed to protect data
during their transmission and to guarantee that data
transmission are authentic
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7. Computer Security
With the introduction of the computer, the need for automated tools for protecting files and
other information stored on the computer was required. The collection of tools designed to
protect data and to thwart (prevent) hackers is computer security.
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8. Cryptography!!!
Cryptography involves creating written or generated codes that allow information to be kept
secret. Cryptography converts data into a format that is unreadable for an unauthorized user,
allowing it to be transmitted without unauthorized entities decoding it back into a readable
format, thus compromising the data.
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9. Cryptography
components
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10. Plaintext and
Ciphertext
• The original message before being transformed through a network by a sender is called
Plaintext.
• After the message is transformed, it is called ciphertext. An encryption algorithm (step by
step data processing) transforms the plaintext intociphertext and decryption algorithm
transforms the ciphertext back into plaintext
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11. Category of Cryptography
Cryptography algorithms can be divided into two group
Symmetric Key Cryptography
In symmetric-key cryptography, the
same key is used by the sender (for
encryption) and the receiver (for
decryption). The key is shared. The
most widely used symmetric algorithm
is AES-128, AES-192, and AES-256.
Asymmetric Key Cryptography
In asymmetric or public key
cryptography, there are two keys, a
private key and a public key. The
private key is kept by the receiver. The
public key is announced to the public.
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12. Comparison between
Symmetric and Asymmetric
Symmetric Encryption
o Symmetric encryption uses a single key that needs to be
shared among the people who need to receive the message
o Symmetric encryption is an old technique
o symmetrical encryption model, eliminating the need to share
the key by using a pair of public-private keys.
Asymmetric encryption
o Asymmetrical encryption uses a pair of public key and a private key
to encrypt and decrypt messages when communicating.
o Asymmetric encryption is relatively new.
o Asymmetric encryption was introduced to complement the inherent
problem of the need to share the key
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13. THANK YOU!
• Eshrak Ur Rahman
• Md Tuhin
• Nasib Muhammad Arif