Cryptography is a cornerstone of modern Information and Communication Technology (ICT), serving as a robust mechanism to secure information and communications. By transforming data into unreadable formats, it ensures confidentiality, integrity, and authenticity. This digital safeguard is indispensable for protecting sensitive information in various applications, from secure communications to identity management.
An Overview Of Cryptography
About: It plays a vital role in securing information and communication within the vast realm of Information and Communication Technology (ICT).
- It’s like a digital shield, protecting sensitive data from prying eyes and ensuring its integrity during transmission or storage.
Here’s How cryptography permeates the ICT landscape
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- Encryption: Messages are transformed into unreadable code using mathematical algorithms and secret keys.
- Only authorized recipients with the corresponding key can decipher the message.
- This safeguards confidential information exchanged over email, online banking, and even video conferencing.
- Digital Signatures: Cryptography allows to create a unique digital fingerprint of the data, ensuring its authenticity and preventing tampering.
- This is crucial for contracts, financial transactions, and software updates.
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- Data at Rest: When storing sensitive data on hard drives or in cloud servers, encryption scrambles it into an unreadable format.
- Even if hackers gain access to the storage, they’ll face a formidable wall of complex code.
- Data in Transit: As data travels across networks, it’s vulnerable to interception.
- Encryption secures data transmission, protecting credit card information during online purchases or medical records during transfer between hospitals.
- Identity and Access Management
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- Authentication: Cryptography verifies the identity of users trying to access systems or information.
- This can involve password encryption, digital certificates, or even biometric authentication like fingerprints or facial recognition.
- Authorization: Once authenticated, users are granted specific access levels to data and systems.
- Cryptography plays a role in defining and enforcing these access controls, ensuring only authorized individuals can perform certain actions.

Digital Signature
About: It is a secure way to electronically sign documents and other digital files.
- It’s like a traditional handwritten signature, but it’s created using cryptography, a branch of mathematics that deals with secure communication in the presence of adversaries.[UPSC 2019]

How does it works?
- Creating the Signature: The signer uses a private key to create a unique code that is mathematically linked to the document.
- This code is like a digital fingerprint of the document and the signer’s identity.
- Verifying the Signature: The recipient uses a public key, which is mathematically paired with the private key, to verify the signature.
- The public key is like a lock that only the private key can open.
- If the signature is valid, it means that the document has not been tampered with and that it was signed by the person who claims to have signed it.
- Digital signatures are used in a wide variety of applications such as:
- E-commerce: Digital signatures are used to secure online transactions;
- Software distribution: Digital signatures are used to verify the authenticity of software downloads;
- Contract signing: Digital signatures are used to sign contracts electronically;
- Healthcare: Digital signatures are used to secure patient records.
Digital Signature Certificates (DSCs) and their Legality in India
In India, digital signature certificates (DSCs) are legally valid and recognized as equivalent to handwritten signatures under the Information Technology Act, 2000 (IT Act, 2000). |
Conclusion
Cryptography is integral to maintaining security and trust in the digital world. By protecting data in transit and at rest, and enabling secure authentication and authorization, it fortifies the ICT infrastructure. As digital interactions continue to expand, the role of cryptography in ensuring secure and reliable communication becomes increasingly crucial.