The document provides an overview of operating systems, including: - An operating system manages hardware and provides services to computer programs through a cycle of hardware, OS, applications, and users. Real-time OS are for executing real-time applications with predictable responses to events. - Common operating systems include Unix, Linux, Mac, Windows, Android, AIX, HP-UX, and Solaris. Distributed OS appear as one computer across many, and embedded OS are for embedded computer systems. - Middleware provides services to software applications beyond the operating system to facilitate communication and data management between client and server. Development skills involve programming languages, software architecture, algorithms, and scripting.

1. Welcome
to

2. Operating System (OS)
• Set of software that manages the hardware and
provides services to computer programs.
• Cycle Hardware<OS<Application<User.
• Real-time OS are for executing real-time applications
• It is predictable response to Events. Has two aspects:
a) Event Driven b) Time Sharing
• Distributed OS: Many appear as 1 computer
• Embedded OS: For embedded computer System.

3. Different Operating Systems
• Unix: All Console
• Linux: GUI of Linux
• Mac: As known
• Windows: As known
• Android: Mobile OS, Linux wrapped in Java
• AIX: Customized Unix by IBM
• HP-UX: Customized Unix by HP
• Solaris: Customized Unix by Sun Microsystems

4. Architecture (Kernel OS)

6. OSI Model For Networking

7. OSI vs Internet

8. Middleware
• Computer Software that provides services to
software applications beyond Operating System.
• It makes it easier for developer to perform
communication (I/O) so that they focus on
purpose of application.
• Communication & Mgmt of data ‘Dash in client-
server’
• Software layer that lies between OS &
Application.

9. Development Skills
• Languages: Assembly, C, C++, Java, .Net
• Difference between C & C++.
• OOPS
• Module Prog. & S/W architecture.
• Algorithm & its Optimization.
• Scripting: Perl, Shell, Tcl, Python.

10. Software Testing
• Black-Box Testing: Internal System design not considered but based on
Requirement and functionality. (Not so strong).
• White-Box Testing: Internal Logic, mainly codes (Strong).
• Unit Testing: Components & modules.
• Integration Testing: Bottom Up approach.
• Functional Testing: Output as per Req.
• System Testing: Entire system is tested as per requirement.
• End to End Testing: Similar to System, but involves real world testing
(database,network,hardware).
• Sanity Testing: Testing of Software versions.
• Regression Testing: Testing whole application if any change in module or
functionality.
• Acceptance Testing: System meeting customer requirements.
• Load Testing: Testing system under load.
• Stress Testing: System is stressed beyond its application.(data,query,connections).
• Performance Testing: How system performing under different loads.
• Usability Testing: Is customer understanding the system.

11. • Install/Uninstall testing: Recovery from
crash and hardware failure.
• Security Testing: Penetrating via hacking.
• Compatibility Testing: Working on all
platforms.
• Manual Testing: Strong/Values.
• Automation Testing: Test
cases,Scripting,Automation.

12. Security Concepts
• IPSec: Internet Security Protocol is a
protocol suite for securing IP by:
a) Authentication
b) Encrypting each IPv4 & v6 packet
• Works on Internet Layer or Upper Layer.
• SSL: Secure Socket Layer
• TLS: Transport Layer Security
• SSH: Secure Shell

13. IPSec Uses Following Protocols
• Authentication Header
• Encapsulating Security Payloads (ESP).
• Security Associations.
• Common Terms:
• Algorithm, Intergrity, Authentication, Keys,
Encapsulation,Encryption,Protocols.

14. Thanks
Any Questions?