DAT - Data Storage and Security (Lesson)

Data Storage and Security

The general definition of the word storage means to place something somewhere for later use. In technology storage means a place to contain digital information. Digital information includes all types of data. Data includes

Documents - endings .doc, .txt, .rtf, etc.
Print files - endings .pdf
Spreadsheet files - endings .csv, .xls, etc.
Computer programs - system and applications with various endings

System programs - called operating system programs for the programs
Application programs - specialized programs for particular problems or solutions.

Videos - endings with .mp3, .mp4, etc.
Images - endings with .jpg, .png, etc.
Much more - depending on the needs of the person storing the data.

Operating system programs are usually on the hard drive and load to memory (RAM - random access memory) to run the computer. The operating system programs then locate application programs when requested and load them into memory for execution.

A device that stores data is computer hardware that records information and allows it to be retrieved to read or to read and add to the information.

How Do We Create Data that is Stored?

Think of what you do each day? Create a list of items that you do on your cell phone, tablet, computer during the week that is stored as data. Then look at my items as a teacher that I create during a week. Note that this data is growing daily.

Teacher Created or Used Data

New contact phone number
Name, physical address, email address
Calendar items
Create an assignment
Assignment comments
Grades
News Blocks
Email - new and responses
Take pictures
Login to websites
Listen to videos
Listen to music
Text message
Phone calls
Bills owed and paid
Read blogs and occasionally add to the conversation
Learn online
Internet surfing
Find a recipe I saved online
Create a new image with application software

This is just a short list of items that would create data. All of this is stored for later access and analysis if needed.

Here is a list of items that you might create or use as a student.

Many of the same items above
Homework
Social media blogs
Music downloads
And more

What data is stored that is different for a business? Write your list and then look at mine. Remember that these are not absolute lists, the list is based on the type of business.

Budget for accounting
Invoices (bills for customers)
Bank statements
Accounting statements
Inventory
Pictures
Employee information in various forms
Vendor information and associated details
Customer information
Other information depending on the business

Storage requirements for this data depend on the user and the amount of data to be stored.

Storage Media Capacity

Storage Media size, capacity is measured in bytes. Earlier in the course we learned that a byte consisted of 8 bits in binary. Each bit is like an on/off switch. On is a one and off is a zero. So a byte consists of a combination of 0's and 1's. If the byte represents numeric data, all of the bits turned on would represent the number 257.

1111 1111 is + + + + + + +

Which is 128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 257.

The table below details the capacity, the amount of storage space available, on the storage medium. Media is the plural word for the storage item, medium is the singular. Storage is

Storage Capacity and Bytes
Storage Capacity Terms	Number of Bytes (approximate)	Calculated Exact Number of Bytes
Kilobyte (KB)	1 thousand	2¹⁰ = 1,024 bytes
Megabyte (MB)	1 million	2²⁰ = 1,048,576 bytes
Gigabyte (GB)	1 billion	2³⁰ = 1,073,741,824 bytes
Terabyte (TB)	1 trillion	2⁴⁰ = 1,099,511,627,776 bytes
Petabyte (PB)	1 quadrillion	2⁵⁰ = 1,125,899,906,842,624 bytes
Exabyte (EB)	1 quintillion	2⁶⁰ = 1,152,921,504606,846,976 bytes
Zettabyte (ZB)	1 sextillion	2⁷⁰ = 1,180,591,620,717,411,303,424 bytes
Yottabyte (YB)	1 septillion	2⁸⁰ = 1,208,925,819,614,629,174,706,176 bytes
And more to come ...		Capacity continues to grow

Two major words to learn for storage are the words Read and Write.

To Read from a storage medium means to transfer an item (data, information, etc.) from storage to memory usually Random Access Memory (RAM). The item is not removed from the storage medium or changed until it is saved (Write).

To Write to a storage medium means to save changes or new items from working memory back to storage.

Input - the act of reading from a storage medium

Output - the act of writing to a storage medium or physically to paper

Access time - the amount of time that is required to either retrieve an item from storage for processing or write an item to storage. Accessing an item already in memory is quicker than accessing an item in storage. Transfer rates help define the access times.

KBps or kilobytes per second
MBps or megabytes per second
GBps or gigabytes per second

What are the Types of Storage Media?

Media may be volatile or nonvolatile.

Volatile - data or information is gone when the power is off
Nonvolatile - data or information is retained when the power is off

Why do we call some as disk or disc? The "k" is used to magnetic or flash media and the "c" is used with optical media.

Are you wondering? An example of volatile storage is memory. Once the computer is turned off, anything in Random Access Memory (RAM) is gone.

Data Security

The protection measures taken to keep private information secure. Identification and authentication controls are used to secure online data. Information on the internet and networks can be secured by encrypting the data as well. Watch the video below to learn more.

Identification, Authentication, and Encryption

Learn the basics of these ideas in the activity below.

Public and Private Keys

Private and Public Keys are long random hex numbers. The Public key given to others allows them to encrypt information to be sent to you. Your private key is the only associated key that can unlink the information sent and display the data to you. Both keys must be associated to view the data. In the diagram below, Bob has a public key that Alice gives out for people she knows sending her information. Bob can use the public to send Alice information. When Alice gets the information, the public key is combined with the private key to unlock the information for her to read and process. No other pair of keys will work together to decrypt the information.

Data Security

Watch the video below for information concerning public and private encryption keys. A public key is one that you give someone to send you information. A private key is strictly for your computer to interpret the incoming public key information.

Secure Shells

Watch the video below to learn about the use of your computer for important information in a coffee shop or other public non-secured internet service. Learn what a Secure Shell is.

It is important to secure your data in order to keep your private information private and not be attacked by the man in the middle, the eavesdropper. Banking and other financial information should never be transacted in an unsecure location. Your bank number is important and using the unsecure location to transmit banking items is not advised. The key to using and transmitting private data is to make sure you use a secure location and a secure link. Remember to look for the https in the browser link. Others impersonating a bank may use a link that looks similar.

Just as in walking down crowded streets, be aware of your surroundings on the internet and think prior to using when in an unsecure location. Note that our phones are small computers and the same rules apply.

Data Mining

Companies are giving out store cards to their customers in growing numbers. Customers have a loyalty card that when used gives discounts, holds coupons, and assists with identifying the customer with each purchase. Each company then tracks what customers buy, return, possibly the times of day they shop, the days they shop.

With the data gathered the companies/stores can then target the customer with coupons to entice them to buy a new product in the store or maybe uses a coupon enticement for a customer's often bought items to get the customer in the store assuming that the customer will buy more.

Another option is that it has status award points to gain special discounts on gas or other items of interest to the customer to keep them coming back rather than trying other stores.

Data mining, the accumulation and analyzation of data happens in walk-in stores or online. This is currently very big business as long as the customer is enticed to keep buying and using the company's products. After all, no sales would mean no business. Since data is easily gathered and stored due to computer science efficiency, and computer software is available like spreadsheets to analyze big data, companies have found a new marketing method using enticement and the customer's own data.

Data Backup

Regardless of the security of data and the storage media used, data should be backed up in more than one place to ensure that data is not lost due to a storage media failure. Backup is the act of storing your data on another medium in case of loss or failure of the first one. Then you can recover and you have not lost a huge amount of information. No media is fool-proof or lasts forever.

Data Erasure

Prior to disposing of your computer, tablet, phone or other personal device, be sure to erase all personal data from your computer. Companies may be fined huge sums of money for leaving personal data of clients on their computers when old hardware is to be discarded.

To erase data from a computer, delete the data, overwrite the data with nonsense information, using a strong electronic magnetic field to destroy magnetic data, destroy the hardware as in a CD, DVD, or disk platter.

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