1.3 Exchanging Data
No description yet. This curated deck is ready for daily study.
Card preview (24)
What name is given to public and private keys used in asymmetric encryption?
• Key pair
Name the two categories of compression
• Lossy - Lossless
In which type of compression is the quality of a file not degraded?
• Lossless
What is the purpose of encryption?
• To keep data secure during transmission
Name one type lossless compression
• Run length encoding - Dictionary encoding
In which form of encryption do the sender and receiver share the same private key?
• Symmetric encryption
How many keys are used in asymmetric encryption?
• Two (one public and one private)
If person A wants to send a message to person B using asymmetric encryption, which key should they use to encrypt the message? 1) A’s public key 2) A’s private key 3) B’s public key 4) B’s private key
3) B’s public key A message encrypted with B’s public key can only be decrypted with B’s private key, which only B has access to.
What is said to have occured when two keys map to the same hash?
A collision
In which kind of lossless compression are repeated characters replaced by one occurrence and the number of times to repeat the character?
• Run length encoding
What name is given to the process of turning an input into a fixed size value?
• Hashing
Which data structure uses hashing to store information with constant lookup time?
• Hash table
What is meant by compression?
• The process of reducing the space required to store a file
Name two properties that a hashing algorithm should have.
• Low chance of collision • Quick to calculate • Output smaller than input
What is a relational database?
• A database which recognises the difference between entities and uses different tables for each entity.
What is an entity?
• An item of interest about which information is stored.
What is a flat file?
• A database that consists of a single file, usually about one entity.
What is a primary key?
• A unique identifier for each record in a table.
What is a foreign key?
• The attribute which links two tables together
What is a secondary key?
• An index other than the primary key used to search and sort through the database with more convenience and speed.
What does capturing data mean?
• The process of getting the information that will be stored in the database.
What method do banks use to capture data from cheques?
• Magnetic Ink Character Recognition (MICR) is used for all of the details apart from the amount which must be entered manually.
What does selecting data mean?
• Selecting data is the process of removing excess information to extract only the data you require
What does managing the data mean?
• To manipulate the information collected in any type of way such as through sorting through it or selecting certain parts using SQL.