ECS - Week 4 Flashcards
What is cryptography ?
Cryptography is the study of secure communications techniques that allow only the sender and intended recipient of a message to view its contents.
Cryptography is the art of keeping information secret and safe by transforming it into form that unintended recipients cannot understand.
What are the 3 stages of data ?
- Data in rest - Data is stored in hard disk
- Data-in-motion - Data transferring on network
- Data in use - Data is use by applications, data in Ram,registers etc
What is the special case of data at rest , securing data in motion ?
Data-at-rest can be thought of data flowing 10th temporally, data travel through time temporary .
Data at rest means data is in pendrive or hard disk, somebody stole your pen drive, then this should be considered as data at rest is in motion
You have a gmail password saved in textfile in pendrive, who stole pendrive can accesses gmail , two simultaneous logins at thr same time
What is secure communication model ?
Confidentiality : Secure Channel,Encryption over Public Network
Integrity - Unchanged Data Data
Authenticity - User Exists on Server
What is confidentiality ?
Protecting data from unauthorised users
How we can confidentiality achieved ?
Securing communication channel medium ?
What is encryption ?
Encryption is the method of encoding plain text into cypher text
What is ciphertext ?
Encoded string of plain text
Encrypting the plain text with the shared key
Who is Auguste Kerckhoff?
Dutch Linguistic and cryptographer during 19th century
What is Kerckhoffs’s principle
Kerckhoff’s principle is the concept that a Cryptographic system should be designed to be secure, even if all its details, except for the key, are publicly known. Only the key is kept secret
It means everything is known to public accept the key.
Keeping small keys secure is much easier than keeping the whole system secure
Changing the whole algorithm is a very hard task, but we can change the key on every time frame
How many principles of wrote by Auguste Kerckhoff
Wrote six principles for practical cypher for design
Which Kerckhoff principle is used in today cyber security
Second principle
What are symmetric key algorithm
Symmetric key algorithm based on a simple principle,
The same key is used for encryption and decryption
What is the what is the drawback of symmetric key algorithm ?
Shared key should be pre-shared to get algorithms to work
What is data authentication
When communication is happening between A and B,
B want to verify that data is coming from actual source A.
This is called data authentication
Verifying the Actual Source of Data is coming from.
