Operating Systems - Process Scheduling Quick Revision Notes

• Process: 

1. It is a program in execution. 
2. It is a unit of work in the modern time sharing system
3. A process is of two types: 1. Operating System Process: It executes system code 2. User Process: It executes user code.

• A process includes: 

1. Program Code (text section)
2. Current Activity (Represented by value of program counters and content of registers of process
3. Process Stack (contains temporary data)
4. Data Section (Global variable)

• Difference between a process and a program: 

A program is a passive entity (Example: contents of file stored in a disk) whereas a process is an active entity (has a program counter specifying next activity to execute). 

• Process State: It is defined by the current activity part of process. Note: Only one process can be in running state.

• Process Control Block: Each project is represented in Operating System using PCB (Process control block or task control block).

To be Continued...

What is Cloud & Definition of Cloud?

Definition of Cloud

A cloud is basically a network of remote servers that is hosted on the internet.

• Cloud in Cloud Computing: Cloud is often used in the context of cloud computing. Cloud Computing: It is location independent technology concept in which a large number of computer systems are connected together using a real time communication network and thus allow those computers to share hardware and software resources. It provides a workload shift to the local computers for they don’t need to process the data. They are just used for accessing data. This allows faster and efficient data processing.
• Cloud in Telecommunications: In telecommunication, cloud refers to a public or smei public space that exists on transmission lines.
  Data that is transmitted through WAN enters the network through one end point using some standard protocol and then enters the network cloud where it shares the space with many other data transmission that happen in the same network

Cloud Characteristics

 There are three main characteristic in a cloud service:

1. Cloud service is sold on demand.
2. Cloud Service is elastic i.e. a user can have as much or as little service through cloud according to his own will and need.
3. Cloud service is fully managed by the service provider.

Types of Cloud

1. Public Cloud: It is the one that sells services to anyone on the internet. For example:  Amazon Web Services is one of the largest public cloud providers.
2. Private Cloud: The services are available to a limited number of people.
3. Virtual Private Cloud: when a service provider uses the resources of a public cloud to create a private cloud, the resulting cloud service is referred to as virtual private cloud.

Note: Check the masterguide to cloud computing notes to browse more topics

Master Guide to Cloud Computing Notes

The topic covered on this blog are linked below:

MODULE 1: OVERVIEW OF CLOUD COMPUTING

1. What is a cloud & Definition of cloud
2. Characteristics of Cloud
3. Why use cloud?
4. How clouds are changing?
5. Driving Factors towards cloud
6. Comparing grid with other computing systems
7. Workload patterns for cloud
8. Big Data
9. IT as a service

MODULE 2: CLOUD COMPUTING CONCEPTS

1. Concepts of cloud computing'
2. Cloud computing leverages the internet
3. Positioning cloud to a grid infrastructure
4. Elasticity and Scalability
5. Virtualization
6. Characteristics of Virtualization
7. Benefits of Virtualization
8. Virtualization in Cloud Computing
9. Hypervisors
10. Multi Tenancy
11. Types of Tenancy
12. Application Programming Interfaces (API)
13. Billing and metering of services
14. Economies of scale
15. Management in CC
16. Tooling in CC
17. Automation in CC
18. Desktops in cloud security

MODULE 3: CLOUD SERVICE DELIVERY

1. Cloud Service
2. Cloud Service Model Architecture
3. Infrastructure as a Service (IaaS)
4. IaaS details
5. Platform as a Service (PaaS)
6. PaaS details
7. Software as a Service (SaaS)
8. SaaS details
9. Examples of SaaS applications
10. Tradeoff in cost to install
11. Common cloud management platform reference architecture 
12. Architecture overview diagram

MODULE 4: CLOUD DEPLOYMENT SCENARIOS

1. Cloud deployment models
2. Public Cloud
3. Hybrid Cloud
4. Community Virtual Private clouds
5. Vertical & Special Purpose
6. Migration paths for clouds
7. Selection Criteria for Cloud deployment

MODULE 5: SECURITY IN CLOUD COMPUTING

1. Cloud security Reference Model
2. How security gets integrated
3. Cloud Security
4. Understanding Security Risks
5. Principal security dangers to cloud computing
6. Virtualization and multi -tenancy
7. Internal Security breaches
8. Data corruption or loss
9. User account and service hijacking
10. Steps to reduce cloud security breaches
11. Reducing cloud security
12. Identity management: detection and forensics
13. Benefits of identity
14. Encryption Techniques
15. Encryption & Encrypting Data
16. Symmetric Key Encryption
17. Asymmetric Key Encryption
18. Digital Signature
19. What is SSL?

MODULE 6: CASE STUDIES

1. IBM Smart Cloud
2. Amazon Web services
3. google Cloud Platform
4. Windows Azure Platform
5. Comparison of different platforms
6. Common building blocks

Note: To request for more topics, send an email to manpreetkaur.aiesec@gmail.com with subject: REQUEST FOR NOTES

What to expect from Information Technology Notes?

I know this post would seem to be really useless for people who are looking for some specific kinds of content like notes on a particular IT subject or so on; but still I had to do one introduction post over here before beginning with what I have planned for this space over the web.

WHO AM I?

I am a blogger and a youtuber. But before that, I studied Information Technology - a bachelor degree (B.Tech.) in Information Technology from a reputed college in India.  

WHY AM I HERE?

When I was doing engineering, I faced a really tough time. My teachers expected me to keep my 80%+ percentile and that was so difficult when I had to manage so many things like blogging, other things and work I liked to do and above all, making notes. It was impossible to learn one topic from one source. You needed to refer to tons of different sources before preparing notes of one single topic and believe me, there were hundreds of topics and it was a pain to go through so many topics at one time.

And I realized that the same would have been happening to so many people out there. Like me, many others would be struggling to get the right and enough material to write long exam papers. 

And that's why I felt I can help you out. If my life wasn't easy, that doesnt mean yours has to be difficult too. You deserve to live  tension free life and this is what I aim for over here.

To provide you detailed notes on various subjects that I studied during my Engineering Degree.

I hope you I would be able to make your life easier. :)