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BSNL LDCE EXAM 2015 LDR Information Technology
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BSNL LDCE EXAM 2015
Last Day Revision [LDR] Guide
Information Technology
Created By ExamKart
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Index
Sr No Chapters 1 Chapter 1 :IT Security 2 Chapter 2: Cyber Security 3 Chapter 3:ERP 4 Chapter 4:Cloud Computing 5 Chapter 5:WWW 6 Chapter 6:OSI Model 7 Chapter 7:Ethernet 8 Chapter 8:Computer Networking /LAN/WAN 9 Chapter 9: Oracle Database
10 Chapter 10:Multimedia Services 11 Chapter 11:E-Governance/E-Commerce/E-Medicine 12 Abbrievations
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Chapter 1 - Information Security
Information security, sometimes shortened to InfoSec, is the practice of defending
information from unauthorized access, use, disclosure, disruption, modification,
perusal, inspection, recording or destruction
Information Security [AIC Model or AIC Triad] ensures
Availability: guarantee of reliable access to the information by authorized people. Integrity : assurance that the information is trustworthy and accurate Confidentially of information : set of rules that limits access to information
Access control is of three steps 1.Identification: Assertion of who someone is or what something is 2.Authentication: Act of verifying a claim of identity. 3. Authorization: permission of access and what actions they will be allowed to perform (run, view, create, delete, or change).
Reasons for Security Incidents Lapse or negligence Malicious Code Attacks Known Vulnerabilities Configuration Errors
Symtoms of a system infected with malicious codes Poor System Performance Abnormal System Behavior Unknown Services are running Crashing of Applications Change in file extension or contents Hard Disk is Busy
Reasons for Vulnerability of the systems Default Accounts Default Passwords Un-necessary Services Remote Access Logging and Audit Disabled Access Controls on Files
Security has to implemented at mainly 4 levels
Network NOS [Network Operating System] Application RDBMS [Relational Database Management System]
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Security of Network: Firewalls are used for Perimeter Defence of Networks. Using Firewall, Access Control Policy is implemented i.e controlling all internal and external traffic.
Security of OS/NOS Keep up-to-date Security Patches and update releases for OS Install up-to-date Antivirus Software Harden OS by turning off unnecessary clients, Services and features
Security of Application Keep up-to-date Security Patches and update releases for Application Package Preventing usage of unauthorized and unsafe software Precautions with Emails Protection from Phishing attacks Securing Web Browsers
Security of RDBMS User Access Control Password Policy Management Managing Allocation of Resources to Users Backup and Recovery Auditing
BSNL has formulated its Information Security Policy known has BISP and circulated
for its implementation during December 2008.
BISP consists of Two sections 1. Section A: Directives and policies that would be followed in ICT facilities within
BSNL to provide secure computing environment for BSNL employees and business.
The policies are formulated around 11 domains of security
1. Information Classification and Control : Information Classification, Information
Labelling & Handling
2. Physical and Environmental Security : Security of the Information System
Equipment, Clear Desk and Clear Screen Policy
3. Personnel Security: User Responsibilities / Accountability, Security during Hiring,
Transfer and Termination
4. Logical Access Control :User Access Management
5. Computing Environment Management: Identification of Hardware
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6. Network Security: Remote Access, Network Diagnostic Tools
7. Internet Security: E-mail Security, Firewall Security
8. System Development and Maintenance: Testing, Source Code Management
9. Business Continuity Planning: Backup and Recovery Procedures, Contingency
Planning
10. Compliance: Use of unauthorised software, Purchasing and regulation of Software
Use
11. Third Party and Outsourcing Services: Risk Assessment, Access Control, Service
Level Agreements
Section B provides the technical solution support to the policies mentioned within the policy document.
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Chapter 2 Cyber Security
Cybersecurity is the process of applying security measures to ensure confidentiality, integrity, and availability of data.
Vulnerabilitiy:A vulnerability is a weakness which allows an attacker to reduce a
system's information assurance. A security risk may be classified as a vulnerability
Vulnerability is the intersection of three elements: 1. a system susceptibility or flaw 2. attacker access to the flaw, 3. attacker capability to exploit the flaw.
Different Types of Vulnerabilities
Backdoors :A backdoor in a computer system is a method of bypassing normal
authentication, securing remote access to a computer, obtaining access to plaintext, and so on, while attempting to remain undetected
Rootkit: A specific form of backdoor is a rootkit, which replaces system binaries
and/or hooks into the function calls of an operating system to hide the presence of
other programs, users, services and open ports. It may also fake information about
disk and memory usage.
Denial-of-service attack [DOS] : is a type of DOS attack where multiple
compromised systems -- which are usually infected with a Trojan -- are used to
target a single system causing a Denial of Service (DoS) attack.
Eavesdropping :Eavesdropping is the act of surreptitiously listening to a private conversation, typically between hosts on a network.
Spoofing:Spoofing of user identity describes a situation in which one person or
program successfully masquerades as another by falsifying data. Tampering:Tampering describes an intentional modification of products in a way
that would make them harmful to the consumer. Repudiation:Repudiation describes a situation where the authenticity of a
signature is being challenged. Exploits:An exploit is a software tool designed to take advantage of a flaw in a
computer system.
Zombie : A zombie is a computer connected to the Internet that has been compromised by a hacker, computer virus or trojan horse and can be used to perform malicious tasks of one sort or another under remote direction. Botnets of zombie computers are often used to spread e-mail spam and launch denial-of-
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service attacks. Most owners of zombie computers are unaware that their system is being used in this way. Because the owner tends to be unaware, these computers are metaphorically compared to zombies.
Logic Bombs:Logic bombs are small programs or sections of a program triggered by some event such as a certain date or time, a certain percentage of disk space filled, the removal of a file, and so on. For example, a programmer could establish a logic bomb to delete critical sections of code if she is terminated from the company. Logic bombs are most commonly installed by insiders with access to the system.
Trap doors: Trap doors, also referred to as backdoors, are bits of code embedded
in programs by the programmer(s) to quickly gain access at a later time, often during the testing or debugging phase. If an unscrupulous programmer purposely leaves this code in or simply forgets to remove it, a potential security hole is introduced. Hackers often plant a backdoor on previously compromised systems to gain later access. Trap doors can be almost impossible to remove in a reliable manner. Often, reformatting the system is the only sure way.
Phishing is the attempt to acquire sensitive information such as usernames, passwords, and credit card details (and sometimes, indirectly, money) by masquerading as a trustworthy entity in an electronic communication.
Computer Virus: A computer virus is a malware program that, when executed, replicates
by inserting copies of itself (possibly modified) into other computer programs, data files,
or the boot sector of the hard drive; when this replication succeeds, the affected areas are
then said to be "infected".
Life Cycle of Virus
A typical virus cycles through 4 phases in its lifecycle
1.Dormant phase
2.Propagation phase
3.Triggering phase
4.Execution phase
1. Dormant phase: The virus is idle. The virus will eventually be activated by some event.Eg:A date,The presence of another program or file,The capacity of the disk exceeding some limit. 2.Propagation phase: The virus places an identical copy of itself into other programs or into certain system areas on the disk. Each infected program will now contain a clone of the virus, which will itself enter a propagation phase. 3.Triggering phase: The virus is activated to perform the function for which it was intended. Can be caused by a variety of system events 4.Execution phase:: The goal of the virus software is performed. e.g. deletion of program or data filling
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Types of Viruses & Malware
1.Worms :A worm is malware that uses computer networks and security holes to
replicate, or affect other programs. A copy of the worm passes through the network to
another machine that has a specific security hole. It then copies itself to the new machine,
and then starts replicating from there.
2.Trojan Horses or Trojans :Trojan Horses are programs that claim to perform a particular function but which in fact do something different. They provide entry point to other viruses & malware.For example, they could infect your computer with a virus and erase your files. 3.Macro Viruses : Macro viruses use commands called macros embedded in other software to infect and spread to other files viewed by that software. For example, Microsoft Word and Excel have macros, and macro viruses can spread by exploiting these commands. 4. Boot Sector Viruses :infect computers startup programs, so that the virus would become active as soon as the computer started up.
5.Backdoor Trojans: Backdoor Trojans are programs that allow other computer users to remotely control your computer via a Local Area Network or the Internet.
6.Resident Viruses :This type of virus hides permanently in the RAM memory. Corrupts files and programs that are opened, closed, copied etc. 7.Direct Action Viruses:When a specific condition is met (such as the execution of the virus), these viruses will go into action and infects files in the directory or folder 8.Overwrite Viruses: Deletes the information contained in the files that it infects, rendering them partially or totally useless once they have been infected.
System Behaviour affected by Virus The computer runs more slowly than normal The machine stops responding or locks up often The system frequently restarts automatically Although the computer restarts on its own, it fails to run normally
Cryptography :Cryptography is used in information security to protect information from
unauthorized or accidental disclosure while the information is in transit (either
electronically or physically) and while information is in storage.
Information security uses cryptography to transform usable information into a form
that renders it unusable by anyone other than an authorized user; this process is called
Encryption.
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Information that has been encrypted (rendered unusable) can be transformed back into its
original usable form by an authorized user, who possesses the cryptographic key,
through the process of Decryption.
Cryptography Algorithms: AES (Advanced Encryption Standard),DES etc
Cookie :A cookie, also known as an HTTP cookie, web cookie, Internet cookie, or
browser cookie, is a small piece of data sent from a website and stored in a user's web
browser while the user is browsing that website. Every time the user loads the website,
the browser sends the cookie back to the server to notify the website of the user's previous
activity.
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Chapter 3 - Enterprise Resource Planning
ERP: is a system used to integrate the data and processes of an organization into one single
system
ERP Features Improvement in the information flow
Better and Timely Inputs of better decision making
Improvements in productivity, cycle time, financial performance and information transparency
Accurate and real-time information availability
Visibility on product and service costs
Unified platform for one integrated organization view
Overall improvement in the performance of the organization
Enable BSNLs vision To become the largest telecom Service Provider in Asia
Important BSNL partners for ERP project are
1. M/s HCL Infosystem as System Integrator [SI]
2. M/s SAP as ERP Solution Provider
3. M/s E&Y as Business Process Re-engineering [BPR] consultant
Modules in ERP system
Finance And Management Accounting (FICO)
Materials And Inventory Management including e-procurement (MM)
Plant/Equipment Maintenance (PM)
Human Resources Management & Administration (HRM)
Sales And Distribution(S&D)
Project Systems (PS)
Real Estate And Telecom Infrastructure Management (REM)
Production Planning (PP)
Supply Chain Management (SCM)
Business Information System (BIS)
Business Intelligence & Analytics (BIA)
Strategy Enterprise Management (SEM)
Quality Control (QC)
Enterprise Portal (EP)
CDR Project data Centers in BSNL : Two 1. Primary ERP site: Hyderabad 2. Disaster Recovery [DR] site: Kolkata
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User Access Network for ERP 1. Use of CDR Network The computer, on which ERP access is required, has to be connected to the CDR network. Intranet being rolled out in CDR Project is the default network for ERP as well.
95 % of the users will get covered in this. Security systems, Access control system, identity management etc. UPS, Storage etc of CDR system shall be used.
2. VPNoBB Network
The locations where the reach of CDR network is not possible, mainly if the numbers of users in a building is less than 5, then VPNoBB can be used. Each PC shall be given a VPNoBB connection
Development Centre for ERP is being setup at ALTTC Ghaziabad.
POC Phase of ERP implementation shall cover Corporate office, Karnataka Telecom Circle,
MH telecom circle, STR, WTP, ALTTC and Telecom Factory Mumbai
3 categories of ERP servers
1.Development server :in which the application will be first developed.
2.Quality server: in which the developed application will be tested. This server is also
used for training of users.
3.Production server: in which the application will finally come to end user. The users will
be interacting with the production server only.
BSNL ERP Project Execution Steps AS-IS: The existing processes of BSNL are captured and documented.
BPR [Business Process Re-engineering]: The consultant evaluates the existing
practices and compares with the best industry practices. Finally the consultant submits it recommendations. These recommendations are discussed in details with the BSNL Sr. Management for acceptance.
BBP [Business Blue Print]: A final document is prepared covering the re-engineered process which is accepted and approved by BSNL for solution design in ERP.
Solution development: As per the final BBP, the solution in the SAP is developed.
Testing :The solution developed is tested. First the individual modules are tested. After that the integrated modules are tested.
Collection of Data: Data is the most important element. The better is the data the
better results are obtained.
Training:Trainings are given to the end users on how to work on the solution developed.
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Go-live: A typical terminology used in ERP project indicating the start of usage of the system by the end-users
ERP Users: BSNL is a service organization. Hence about 50-60% of the executive staff
shall be working on CORE ERP system. The staff working at customer service centers and
involved in selling of Mobile inventory (RC, Top up) and the staff dealing with franchise /
DSA will also use CORE ERP system. Core ERP users shall consume the Licenses of ERP.
Power Users: There will be at least one Power user of each module. The Power user will be responsible to solve day to day issues and to escalate to the appropriate level.
1. SSA/Unit Level Power Users: L1 2. Circle Level Power Users:L2 3. Central Level Power Users (Core team at ERP centre):L3
Interfaces ERP Sanchar Soft: The franchise sale will continue in Sanchar Soft ERP STR Package. CDR ERP. Punjab POI Package This will be completely taken over by ERP HR Package - This will be completely taken over by ERP.
ESS [Employee Self Service] Portal
All Employees i.e Executives as well as Non executives have been given Employee Self
Service (ESS) Licenses of ERP.
Facilities provided in ESS portal
1. Leave Request,Leave History,Leave Quota
2. Claims and Reimbursement [Medical,Telephone Bills,Newspaper,LTC etc]
3. Career History
4. Salary Statement
5. Universal Worklist
ERP Helpdesk Portal [Mantis] :The ERP issues or problems faced by end users are
entered in ERP helpdesk portal and forwarded to L1 user of respective module for
resolution. If L1 user cannot resolve the issue ,he/she will forward it to L2 user ,and if L2
cannot resolve than issue gets forwarded to L3 [core team] for resolution. The issues can
be marked with normal, high ,urgent priority etc.
Important ERP Modules
1. Human Capital Management (HCM) Module:This module helps HR team for efficient
management of human resources. HR module helps to manage employee information,
track employee records like performance reviews, designations, job descriptions, skill
matrix, time & attendance tracking. One of the important sub module in HR module is
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Payroll System which helps to manage salaries, payment repots etc. It can also includes
Travel Expenses & Reimbursement tracking. Employee Training tracking can also managed
by ERP.
2. Financial Accounting & Controlling [FICO] module:Whole inflow & outflow of
money/capital is managed by finance module. This module keeps track of all account
related transactions like expenditures, Balance sheet, account ledgers, budgeting, bank
statements ,payment receipts, tax management etc.
3. Material Management [MM] Module:MM modules take care of all the processes that are
part of procurement of items or raw materials that are required for organization. MM
module consist of functionalities like supplier/vendor listing, supplier & item linking,
sending quotation request to vendors, receiving & recording quotations, analysis of
quotations, preparing purchase orders, tracking the purchase items, preparing GRNs(Good
Receipt Notes) & updating stocks & various reports . MM module is integrated with
Inventory module & Engineering/production module for updating of stocks.
4. Plant Maintenance [PM] Module :Plant Maintenance module deals with repair and
maintenance of Equipments. For eg: Repair and Maintainance of IT assets like computer
& accessories ,Field Equipments like OTDR , Vehicles etc can be done under this
module.This module can also be used to track the stock of items or assets. Asset can be
identified by unique serial numbers. Using that unique numbers inventory system can keep
track of item and trace its current location in organization.
5. Sales & Distribution [S&D] Module :Typical sales process includes processes like Sales
queries & enquiry analysis & handling, quotation drafting, accepting sales orders, drafting
sales invoices with proper taxation, dispatch/Shipment of material or service, tracking
pending sales order . CRM module can take help of Sales module for future opportunity
creation & lead generation.
6. Project System [PS] Module: PS Module mainly deals with the management and
implementation of the project .For Eg: Project Estimate ,Detailed Estimate of the project
can be prepared under this module .
7. Real Estate & Management [REM] Module: REM Module deals with management of real
estate assets. For eg: Management of Land,Building ,Rental Buildings/Land can be done
under this module.
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IMP ERP T-Codes
1. Material Management (MM ) Module
Sl No TX Code Description 1 Me51n Creation of PR 2 Me52n Changing PR 3 Me53n Display PR 4 Me54n PR release 5 Me41 Entering quotation (blank) RFQ 6 Me90 Print quotation 7 Me47 Entering quotation details 8 Me49 Price comparison of quotation 9 Me45 Release purchasing document 10 ZMMR_REL Status of release report 11 ML81N SES entry 12 Me21N Creation of PO 13 ZMMP_INI_AMEND Amending PO 14 Me29n Release of PO 15 MIGO Goods receipt
2. Real Estate Management (REM) Module
Sl No TX Code Description 1 REISBE Information on Buisness Entity 2 REISBU Information on Building 3 REISPR Information on Land 4 REISRO Information on Rental Object 5 REBDPR Process Land 6 REDBDBU Process Building 7 REBDRO Process Rental Object
3. Financial Accounting & Controlling (FICO) Module
Sl No TX Code Description 1 FB50 GL Document Posting 2 FB02 To Change Document 3 F-04 Post With Clearing 4 FB08 Reversal of Doc
4.Plant Maintenance (PM) Module
Sl No TX Code Description 1 IE01 Create Equipment 2 IH01 Display list of Equipment 3 IW31 Create Order 4 IW21 Create Notification
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5.Human Capital Management (HCM ) Module
Sl No TX Code Description 1 PA10 Display personal file of employee 2 PA20 Display Master Data 3 PA30 Maintain Master Data 4 PQ10 Create Circle 5 PQ01 Create Work Center
6.Project Systems (PS) Module
Sl No TX Code Description 1 CJ01 Create Project Definition 2 CJ02 Create WBS Structure 3 CN21 Create Network element 4 IM52 Budget Allocation 5 CJ30 Budget Distribution
7.Sales & Distribution (S&D) Module
Sl No TX Code Description 1 ZCMSALES Franchisee sales (Sales
order,Payment,Delivery,invoice)
8.Basis Module
Sl No TX Code Description 1 SU01 Password Reset
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Chapter 4 Cloud Computing
Cloud computing is a model for enabling convenient, on-demand network access to a
shared pool of configurable computing resources (e.g., networks, servers, storage,
applications, and services) that can be rapidly provisioned and released with minimal
management effort or service provider interaction.
In simple terms , Cloud computing is a subscription-based service where you can obtain networked storage space and computer resources.
Features of Cloud Computing 1. On-demand self-service: This means provisioning or de-provisioning computing
resources as needed in an automated fashion without human intervention. An analogy to this is electricity as a utility where a consumer can turn on or off a switch on-demand to use as much electricity as required.
2. Ubiquitous network access. This means that computing facilities can be accessed from anywhere over the network using any sort of thin or thick clients (for example smartphones, tablets, laptops, personal computers and so on).
3. Resource pooling: This means that computing resources are pooled to meet the demand of the consumers so that resources (physical or virtual) can be dynamically assigned, reassigned or de-allocated as per the requirement. Generally the consumers are not aware of the exact location of computing resources. However, they may be able to specify location (country, city, region and the like) for their need. For example, I as a consumer might want to host my services with a cloud provider that has cloud data centers within the boundaries of India
4. Rapid elasticity: Cloud computing provides an illusion of infinite computing resources to the users. In cloud models, resources can be elastically provisioned or released according to demand. For example, my cloud-based online services should be able to handle a sudden peak in traffic demand by expanding the resources elastically. When the peak subsides, unnecessary resources can be released automatically.
5. Measured service: This means that consumers only pay for the computing resources they have used. This concept is similar to utilities like prepaid mobile ,pay as much you talk.
Types of clouds There are different types of clouds that you can subscribe to depending on your needs. 1. Public Cloud - A public cloud can be accessed by any subscriber with an internet
connection and access to the cloud space. As a home user or small business owner, you will most likely use public cloud services.
2. Private Cloud - A private cloud is established for a specific group or organization and
limits access to just that group.
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3. Community Cloud - A community cloud is shared among two or more organizations that have similar cloud requirements.
4. Hybrid Cloud - A hybrid cloud is essentially a combination of at least two clouds, where the clouds included are a mixture of public, private, or community.
Three Main types of Cloud Services These three types differ in the amount of control that you have over your information, and conversely, how much you can expect your provider to do for you.
1. Software as a Service [SaaS] - A SaaS provider gives subscribers access to both resources and applications. SaaS makes it unnecessary for you to have a physical copy of software to install on your devices. SaaS also makes it easier to have the same software on all of your devices at once by accessing it on the cloud. In a SaaS agreement, one has the least control over the cloud.
Examples of SaaS : Google Docs, IBM SmartCloud Docs, IBM SmartCloud Meetings,Saleforce.coms CRM application
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2. Platform as a Service[PaaS] - A PaaS system goes a level above the Software as a Service setup. A PaaS provider gives subscribers access to the components that they require to develop and operate applications over the internet.
Example of PaaS :IBM SmartCloud Application Services and Google App Engine
3. Infrastructure as a Service[IaaS] - An IaaS agreement, as the name states, deals primarily with computational infrastructure. In an IaaS agreement, the subscriber completely outsources the storage and resources, such as hardware and software, that they need. In a IaaS agreement, you have the highest control over the cloud.
Example of IaaS : IBM SmartCloud Enterprise,SoftLayer cloud and Amazon EC2
Cloud Computing in BSNL
BSNL Internet Data Center has six data centres in India. These fully secured data centres
in India are built to Uptime Tier-III and TIA 942 standards.
Six Internet data centers in BSNL are
1. Jaipur Data Centre 2. Mumbai Data Centre
3. Ahmedabad Data Centre 4. Ludhiana Data Centre 5. Ghaziabad Data Centre 6. Faridabad Data Centre
BSNL Public Compute-as-a-Service :enables automated provisioning of virtual servers running Windows or Linux operating systems (OS) in less than 5 minutes. BSNL public cloud service includes customizable virtual servers, secure cloud networking and up to 2.5 TB of block-based storage per server. It support both hourly and monthly pricing plans.
Pay-Per-Use (Usage based): Clients can further utilize our Usage based option (pay-
per-use model) for the different Compute offerings. With this sign-up clients would be
able to use the following resources on truly pay per use model, paying only for the actual
Resources Hours consumed.
BSNL Cloud Services Features Hourly pricing and on-demand provisioning of virtual machines running Windows or
Linux Flexibility to increase or decrease CPU, RAM and Storage on each Cloud Server on the fly 99.99% availability guarantee Hardware-based networking, including VLAN segmentation, customisable firewalls, load
balancing, NAT and multicast Pay-as-you-go or prepaid pricing plans Role-based permissions for multiple users on a single account
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BSNL Cloud Services Pre-packaged Offer Plans
PARTICULARS EXPRESS STANDARD GROWTH POWER SUPREME
No of Virtual CPUs 1 2 4 6 8
RAM (in GB) 1 2 4 6 8
Storage (in GB) 40 60 120 180 240
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Chapter 5 WWW [World Wide Web]
Internet a computer network consisting of a worldwide network of computer networks that use the TCP/IP network protocols to facilitate data transmission and exchange.
What do we need to get connected to internet? Getting on the Internet requires: Computer Modem Telephone Line Internet Service Provider (ISP) Communication Software
Modem: Communication device that allows us to communicate with another computer
through telephone lines. Modulator/Demodulator
Internet Service Provider (ISP) :is a company that allow you to use their internet connection for a price.
When you register with an ISP the followings are given: 1.Username: A unique name that identifies you. 2.Password: A secret code that prevents other people from using your account. Examples of ISP:AT&T WorldNet ,MTNL ,BSNL,Airtel,Vodafone
Tim Berners-Lee invented the World Wide Web (WWW) in 1989
World Wide Web: The World Wide Web, abbreviated as WWW and commonly known as The Web, is a system of interlinked hypertext documents contained on the Internet.
Web Browser : is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. With a web browser, one can view web pages that may contain text, images, videos, and other multimedia and navigate between them by using hyperlinks.
Example of Web Browser: Internet Explorer , Mozilla Firefox, Google Chrome
Universal Resource Locator :Each web page has a unique address called Universal Resource Locator (URL) which contains unique information about the server and the path on the server to find and retrieve the information. Url is also known as web address. Example of URL is http://www.bsnl.co.in
Hyper text transfer Protocol [HTTP] : HTTP is a relatively simple client-server
protocol; a client sends a request message to a server and waits for a response message. HTTP works as a request-response protocol between a client and server. An important property of HTTP is that it is stateless i.e it does not have any concept of open connection and does not require a server to maintain information on its clients
Types of HTTP Requests: Two commonly used methods for a request-response between
a client and server are: GET and POST.
GET - Requests data from a specified resource
POST - Submits data to be processed to a specified resource
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Other Types of HTTP Request
HyperText Markup Language [HTML]: Most Web documents are expressed by means of a special language called being a markup language called HTML which provides keywords to structure a document into different sections. For example, each HTML document is divided into a heading section and a main body.
Document Object Model :When a document is parsed, it is internally stored as a rooted
tree, called a parse tree, in which each node represents an element of that document. Similarly, each node is required to implement a standard interface containing methods for accessing its content, returning references to parent and child nodes, and so on. This standard representation is also known as the Document Object Model or DOM .It is also often referred to as dynamic HTML.
XML: Although most Web documents are still expressed in HTML, an alternative language that also matches the DOM is XML, which stands for the Extensible Markup Language Unlike HTML, XML is used only to structure a document; it contains no keywords to format a document such as centering a paragraph or presenting text in italics.
Web Proxy : In computer networks, a proxy server is a server (a computer system or an application) that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server and the proxy server evaluates the request whether to provide the service or not.
Client: A client is one which sends request to server for fetching information .For eg: A Web Browser like Internet Explorer or Mozilla Firefox can be said to be client on which one can view web pages
Server:A Web server is a program that handles incoming HTTP requests by fetching the requested document and returning it to the client. Eg: Apache server
Search Engine A web search engine is designed to search for information on the World Wide Web. The search results are usually presented in a list of results and are commonly called hits. Example: http://www.bsnl.co.in/GSM/tariff.html 1. http:// protocol rules through which transmission takes place over the internet. 2.www world wide web
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3. bsnl.co.in - server name - domain name 4. GSM/ - pathname to the directory you are requesting 5. tariff.html - filename you are requesting
Hyperlink: A document can contain references to other documents. Such references are known as hyperlinks
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Chapter 6 OSI Model
Open Systems Interconnection (OSI) model is developed by ISO (International
organization for standardization) in 1984.
This model is called Open System Interconnection (OSI) because this model allows any two different systems to communicate regardless of their underlying architecture. Therefore OSI reference model allows open communication between different systems without requiring changes to the logic of the underlying hardware and software.
OSI Model 7 Layers.
The seven layers can be grouped into Three groups 1.Network: Layer 1, 2 and 3 i.e. physical, data link, and network 2.Transport : Layer 4 provides end to end reliable data transmission 3.Application: Layer 5, 6 and 7 i.e. Session, Presentation, and Application layer
OSI model is just a model. It is not a protocol that can be installed or run on any system.
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Layer 7 Application Layer
The application layer makes the interface between the program that is sending or is
receiving data and the protocol stack. When you download or send emails, your e-mail
program contacts this layer. This layer provides network services to the end-users like
Mail, ftp, telnet, DNS.
Protocols used in Application Layer
Function of Application Layer
Resource sharing and device redirection. Remote file access. Remote printer access. Inter-process communication. Network management. Directory services. Electronic messaging (such as mail)
Network Virtual Terminal: A network virtual terminal is a software version of a physical
terminal and allows a user to log on to a remote host. For this, application layer creates a software emulation of a terminal at the remote host. Eg: Emulation Software like Team viewer
Layer 6 Presentation Layer or Translation layer
The presentation layer formats the data to be presented to the application layer. It can be viewed as the translator for the network.
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Functions of Presentation Layer
Character code translation: for example, ASCII to EBCDIC. Data conversion: bit order, CR-CR/LF, integer-floating point, and so on. Data compression: reduces the number of bits that need to be transmitted on the
network. Data encryption: encrypt data for security purposes. For example, password
encryption.
Layer 5 - Session Layer Session layer has the primary responsibility of beginning, maintaining and ending the communication between two devices, which is called Session. The examples of session layers are the interactive logins and file transfer sessions.
Functions of Session Layer
Session establishment, maintenance and termination: allows two application processes on different machines to establish, use and terminate a connection, called a session. Session support: performs the functions that allow these processes to communicate over the network, performing security, name recognition, logging Dialog control: Dialog control is the function of session layer that determines which device will communicate first and the amount of data that will be sent.
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Dialog separation or Synchronization: The session layer is also responsible for adding checkpoint or markers within the message. This process of inserting markers to the stream of data is known as dialog separation.
Protocols: The protocols that work on the session layer are NetBIOS, Mail Slots, Names
Pipes, and RPC.
Layer 4 Transport Layer Transport layer manages end to end (source to destination) (process to process) message delivery in a network and also provides the error checking and hence guarantees that no duplication or errors are occurring in the data transfers across the network.
Transport layer provides two types of services 1. Connection oriented 2. Connectionless 1. Connection Oriented Transmission In this type of transmission the receiving device sends an acknowledgment, back to the
source after a packet or group of packet is received. This type of transmission is also known as reliable transport method. Because connection oriented transmission requires more packets be sent across network,
it is considered a slower transmission method. 2. Connectionless Transmission In this type of transmission the receiver does not acknowledge receipt of a packet. Sending device assumes that packet arrive just fine. This approach allows for much faster communication between devices. The trade-off is that connectionless transmission is less reliable than connection oriented.
Functions of Transport Layer:
Segmentation of message into packet and reassembly of packets into message:
accepts a message from the (session) layer above it, splits the message into smaller units
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(if not already small enough), and passes the smaller units down to the network layer. The transport layer at the destination station reassembles the message.
Message acknowledgment: provides reliable end-to-end message delivery with acknowledgments.
Flow control: Like Data link layer, transport layer also performs flow control. Transport layer makes sure that the sender and receiver communicate at a rate they both can handle. Therefore flow control prevents the source from sending data packets faster than the destination can handle. Here, flow control is performed end-to-end rather than across a link.
Error control: Like Data link layer, Transport layer also performs error control. Here
error control is performed end-to-end rather than across a single link. The sending transport layer ensures that the entire message arrives at the receiving transport layer without error (damage, loss or duplication). Error correction is achieved through retransmission.
Protocols: These protocols work on the transport layer TCP, SPX, NETBIOS, ATP and NWLINK.
Layer 3 Network Layer
This layer is incharge of packet addressing, converting logical addresses into physical addresses. The network layer determines that how data transmits between the network devices.
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Functions of Network Layer Logical-Physical Address Mapping: translates logical addresses, or names, into
physical addresses.
Routing :When independent networks or links are combined together to create internet works, multiple routes are possible from source machine to destination machine. The network layer protocols determine which route or path is best from source to destination. This function of network layer is known as routing.
Packetizing: The network layer receives the data from the upper layers and creates its
own packets by encapsulating these packets. The process is known as packetizing. This packetizing in done by Internet Protocol (IP) that defines its own packet format.
Fragmentation:Fragmentation means dividing the larger packets into small fragments. For this, network layer divides the large packets into fragments so that they can be easily sent on the physical medium.
Protocols: These protocols work on the network layer IP, ICMP, ARP, RIP, OSI, IPX and
OSPF.
Layer 2 - Data Link layer It is responsible for reliable node-to-node delivery of data. It receives the data from network layer and creates frames, add physical address to these frames and pass them to physical layer
Data Link layer consists of two sub-layers
1. Logical Link Control (LLC) sublayer 2. Medium Access Control (MAC) sublayer
1.Logical Link Control (LLC) sublayer :LLC sublayer provides interface between the media access methods and network layer protocols such as Internet protocol which is a part of TCP/IP protocol suite. LLC sublayer determines whether the communication is going to be connectionless or connection-oriented at the data link layer.
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2.MAC sublayer :is responsible for connection to physical media. At the MAC sublayer of Data link layer, the actual physical address of the device, called the MAC address is added to the packet. Such a packet is called a Frame that contains all the addressing information necessary to travel from source device to destination device.
MAC address is the 12 digit hexadecimal number unique to every computer in this
world. A device's MAC address is located on its Network Interface Card (NIC). In these 12 digits of MAC address, the first six digits indicate the NIC manufacturer and the last six digits are unique. For example, 32-14-a6-42-71-0c is the 12 digit hexadecimal MAC address. Thus MAC address represents the physical address of a device in the network.
Functions of Data Link Layer
Link Establishment and Termination: Establishes and terminates the logical link between two nodes.
Physical addressing: After creating frames, Data link layer adds physical addresses (MAC address) of sender and/or receiver in the header of each frame.
Frame Sequencing: Transmits/receives frames sequentially.
Frame Error Checking: Checks received frames for integrity.
Flow control: It is the traffic regulatory mechanism implemented by Data Link layer that prevents the fast sender from drowning the slow receiver. If the rate at which data is absorbed by receiver is less that the rate produced in the sender, the data link layer imposes this flow control mechanism.
Error control: Data link layer provides the mechanism of error control in which it
detects and retransmits damaged or lost frames. It also deals with the problem of duplicate frame, thus providing reliability to physical layer.
Access control: When a single communication channel is shared by multiple devices,
MAC sub-layer of data link layer helps to determine which device has control over the channel at a given time.
Layer 1 Physical Layer
The physical layer, the lowest layer of the OSI model, is concerned with the transmission and reception of the unstructured raw bit stream over a physical medium. It describes the electrical/optical, mechanical, and functional interfaces to the physical medium, and carries the signals for all of the higher layers. Physical layer defines the cables, network cards and physical aspects.
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Functions of Physical layer
Data Encoding: Modifies the simple digital signal pattern (1s and 0s) used by the PC
to better accommodate the characteristics of the physical medium, and to aid in bit and frame synchronization.
Transmission Technique: determines whether the encoded bits will be transmitted
by baseband (digital) or broadband (analog) signaling. Physical Medium Transmission: transmits bits as electrical or optical signals
appropriate for the physical medium Bit synchronization: The physical layer provides the synchronization of the bits
by providing a clock. This clock controls both transmitter as well as receiver thus providing synchronization at bit level.
Bit rate control: Physical layer defines the transmission rate i.e. the number of bits
sent in one second. Therefore it defines the duration of a bit. Line configuration: Physical layer also defines the way in which the devices are
connected to the medium. Two different line configurations are used point to point configuration and multipoint configuration.
Transmission mode: Physical layer also defines the way in which the data flows
between the two connected devices. The various transmission modes possible are: Simplex, half-duplex and full-duplex.
Physical topologies: Physical layer specifies the way in which the different,
devices/nodes are arranged in a network i.e. bus, star or mesh. Multiplexing: Physical layer can use different techniques of multiplexing, in order to
improve the channel efficiency. Circuit switching: Physical layer also provides the circuit switching to interconnect
different networks.
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Chapter 7 - Ethernet
Ethernet is a family of computer networking technologies for local area networks (LANs) and metropolitan area networks (MANs).
Ethernet standardIEEE 802.3: Defines the MAC layer for bus networks that use CSMA/CD
Basic Ethernet Cable Types
Cable Name Makeup Frequency Support
Data Rate Network Compatibility
Cat-5 4 twisted pairs of copper wire -- terminated by RJ45 connectors
100 MHz Up to 1000Mbps
ATM, Token Ring,1000Base-T, 100Base-TX, 10Base-T
Cat-5e 4 twisted pairs of copper wire -- terminated by RJ45 connectors
100 MHz Up to 1000Mbps
10Base-T, 100Base-TX, 1000Base-T
Cat-6 4 twisted pairs of copper wire -- terminated by RJ45 connectors
250 MHz 1000Mbps 10Base-T, 100Base-TX, 1000Base-T
Types of Ethernet
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Standard Ethernet Code
For example: 10 BASE-TX indicates a Fast Ethernet connection (10 Mbps) that uses a twisted pair cable capable of full-duplex transmissions.
10 at the beginning means the network operates at 10Mbps.
BASE means the type of signaling used is baseband.
2 or 5 at the end indicates the maximum cable length in meters.
T the end stands for twisted-pair cable.
X at the end stands for full duplex-capable cable.
FL at the end stands for fiber optic cable.
Ethernet Frame
Example of Ethernet : 10Base-T Ethernet RJ-45
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CSMA/CD [Carrier-sense multiple access with collision detection] CSMA/CD is a set of rules determining how network devices respond when two devices attempt to use a data channel simultaneously (called a collision). Standard Ethernet networks use CSMA/CD. This standard enables devices to detect a collision. After detecting a collision, a device waits a random delay time and then attempts to re-transmit the message. If the device detects a collision again, it waits twice as long to try to re-transmit the message.
The Ethernet address is 6 bytes (48 bits), written in hexadecimal notation, with a colon between the bytes.
For Eg: 06:01 :02:01:2C:4B
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Chapter 8 Computer Networking /LAN/WAN
Computer network : A computer network or data network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections. Data is transferred in the form of packets. The connections (network links) between nodes are established using either cable media or wireless media. The best-known computer network is the Internet.
Network interfaces used in Computer Networking
Hub Bridge Switch Router Wireless Access Point
Repeater
Physical layer
Data Link Layer
Data Link Layer or Network Layer
Network layer
Physical Layer or Data Link Layer
Physical layer
Hub: Hubs cannot filter data so data packets are sent to all connected devices/computers. The device has to make decision if it needs the packet. This can slow down the network overall. Hubs do not have intelligence to find out best path for data packets. This leads to inefficiencies and wastage.
Hubs are used on small networks where data transmission is not very high
Bridge: A bridge is more complex than hub.A bridge maintains a MAC address table for both LAN segments it is connected to. Bridge has a single incoming and outgoing port.
Bridge looks at the destination of the packet before forwarding unlike a hub.It restricts transmission on other LAN segment if destination is not found.
Switch:A switch when compared to bridge has multiple ports.Switches can perform error checking before forwarding data.Switches are very efficient by not forwarding packets that error-ed out or forwarding good packets selectively to correct devices only.
Switches can support both layer 2 (based on MAC Address) and layer 3 (Based on IP address) depending on the type of switch. Usually large networks use switches instead of hubs to connect computers within the same subnet.
Router :A router, like a switch forwards packets based on address.A router uses the IP address to forward packets. Routers forward packets based on software while a switch (Layer 3 for example) forwards using hardware called ASIC (Application Specific Integrated Circuits).Routers support different WAN technologies but switches do not.
Wireless Routers have Access Point built in. The most common home use for routers is to share a broadband internet connection.
Wireless Access Point : bridges wireless and wired traffic. Wireless Access Point allows devices/computers to connect to LAN in a wireless fashion. Wireless Access Point allows wired and wireless devices work to communicate with each other.
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Repeaters : are built into the hubs or switches. Repeaters clean, amplify and resend the signals that have been weakened due to long cables traveling large distances.
Network Toplogies:Network topology is the layout or arrangement of interconnected
nodes of a computer network
Common network topologies 1.Bus Topology Uses a trunk or backbone to which all of the computers on the network connect. Systems connect to this backbone using T connectors or taps. Coaxial cablings (10Base-2, 10Base5) were popular options years ago.
2.Star Topology
All computers/devices connect to a central device called hub or switch. Each device requires a single cable Point-to-point connection between the device and hub. Most widely implemented
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3. Ring Toplology : Data travels in circular fashion from one computer to another on the network. Typically FDDI, SONET or Token Ring technology are used to implement a ring
network Ring networks are most commonly wired in a star configuration
4. Mesh Topology Each computer connects to every other. High level of redundancy. Rarely used.
Wiring is very complicated Cabling cost is high Troubleshooting a failed cable is tricky
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Network Types
1. Local area network [LAN]: A LAN is a group of computers and network devices connected together, usually within the same building. Eg:A networked office building, school, or home usually contains a single LAN, though sometimes one building will contain a few small LANs (perhaps one per room), and occasionally a LAN will span a group of nearby buildings.
2. Metropolitan area network [MAN] : is a larger network that usually spans several buildings in
the same city or town.
3. Wide Area network [WAN]: is not restricted to a geographical location, although it might be
confined within the bounds of a state or country. A WAN connects several LANs, and may be
limited to an enterprise (a corporation or an organization) or accessible to the public. The
technology is high speed and relatively expensive. The Internet is an example of a worldwide
public WAN.
4. Virtual private network (VPN) : is an overlay network in which some of the links between nodes are carried by open connections or virtual circuits in some larger network (e.g., the Internet) instead of by physical wires. VPNs, for example, can be used to separate the traffic of different user communities over an underlying network with strong security features.
Intranets
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Intranet: An intranet is a set of networks that are under the control of a single administrative entity. The administrative entity limits use of the intranet to its authorized users.Eg: BSNL Intranet.
Extranet:An extranet is a network that is also under the administrative control of a single
organization, but supports a limited connection to a specific external network. For example, an organization may provide access to some aspects of its intranet to share data with its business partners or customers.
Internet :An internet is the connection of multiple computer networks via a common
routing technology using routers. It is a global system of interconnected governmental, academic, corporate, public, and private computer networks. It is based on the networking technologies of the Internet Protocol Suite. Internet was founded by the Advanced Research Projects Agency Network (ARPANET) developed by DARPA of the United States Department of Defense. The Internet is also the communications backbone underlying the World Wide Web (WWW).
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Chapter 9- Oracle Database
Database: A database is an organized collection of information treated as a unit. The purpose of a database is to collect, store, and retrieve related information for use by database applications.
Database Management System (DBMS): is software that controls the storage, organization, and retrieval of data.
Typically, a DBMS has the following elements: 1. Kernel code:This code manages memory and storage for the DBMS. 2. Repository of metadata:This repository is usually called a data dictionary. 3. Query language:This language enables applications to access the data.
A database application is a software program that interacts with a database to access and
manipulate data.
Types of the first generation of database management systems: 1. Hierarchical database: organizes data in a tree structure. Each parent record has one or more child records, similar to the structure of a file system. 2.Network Database :A network database is similar to a hierarchical database, except records have a many-to-many rather than a one-to-many relationship.
Relational Model Today, the most widely accepted database model is the relational model. Relational database :is a database that conforms to the relational model. The relational model has the following major aspects: Structures: Well-defined objects store or access the data of a database.
Operations:Clearly defined actions enable applications to manipulate the data and
structures of a database.
Integrity rules : govern operations on the data and structures of a database.
A relational database stores data in a set of simple relations (tables). A relation is a set of tuples. A tuple is an unordered set of attribute values.
A table is a two-dimensional representation of a relation in the form of rows (tuples) and columns (attributes). Each row in a table has the same set of columns. For example, a relational database could store information about company employees in an employee table, a department table, and a salary table.
Relational Database Management System (RDBMS)
The relational model is the basis for a relational database management system (RDBMS). Essentially, an RDBMS moves data into a database, stores the data, and retrieves it so that it can be manipulated by applications.
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An RDBMS distinguishes between the following types of operations: Logical operations:In this case, an application specifies what content is required.
For example, an application requests an employee name or adds an employee record to a table.
Physical operations:In this case, the RDBMS determines how things should be
done and carries out the operation. For example, after an application queries a table, the database may use an index to find the requested rows, read the data into memory, and perform many other steps before returning a result to the user.
Oracle Database: is an RDBMS. An RDBMS that implements object-oriented features
such as user-defined types, inheritance, and polymorphism is called an object-relational database management system (ORDBMS). Oracle Database has extended the relational model to an object-relational model, making it possible to store complex business models in a relational database.
Oracle Database Version:Oracle Database 11g, released in 2007, introduced a host of new features that enable administrators and developers to adapt quickly to changing business requirements. The key to adaptability is simplifying the information infrastructure by consolidating information and using automation wherever possible.
Common Terminologies used in Oracle Database
Schema Objects :In Oracle Database, a database schema is a collection of logical data structures, or schema objects. Schema objects are user-created structures that directly refer to the data in the database. The database supports many types of schema objects, the most important of which are tables and indexes.
Tables:A table describes an entity such as employees. You define a table with a table name, such as employees, and set of columns. A table is a set of rows.
A column identifies an attribute of the entity described by the table, whereas a row identifies an instance of the entity. For example, attributes of the employees entity correspond to columns for employee ID and last name. A row identifies a specific employee.
Indexes:An index is an optional data structure that you can create on one or more
columns of a table. When processing a request, the database can use available indexes to locate the requested rows efficiently. Indexes are useful when applications often query a specific row or range of rows.
Languages used in RDBMS
1. Structured Query Language (SQL)
SQL is a set-based declarative language that provides an interface to an RDBMS such as Oracle Database. In contrast to procedural languages such as C, which describe how things should be done, SQL is nonprocedural and describes what should be done. All
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operations on the data in an Oracle database are performed using SQL statements. For example, you use SQL to create tables and query and modify data in tables.
A SQL statement can be thought of as a very simple, but powerful, computer program or instruction. Example of SQL Statement: SELECT first_name, last_name FROM employees;
Tasks performed by SQL statements Query data Insert, update, and delete rows in a table Create, replace, alter, and drop objects Control access to the database and its objects Guarantee database consistency and integrity
2. PL/SQL
PL/SQL is a procedural extension to Oracle SQL. PL/SQL is integrated with Oracle Database, enabling you to use all of the Oracle Database SQL statements, functions, and data types. You can use PL/SQL to control the flow of a SQL program, use variables, and write error-handling procedures.A primary benefit of PL/SQL is the ability to store application logic in the database itself.
Features of RDBMS 1.Data Concurrency:A requirement of a multiuser RDBMS is the control of concurrency, which is the simultaneous access of the same data by multiple users. For example, one user could update a row while a different user simultaneously updates it.
Oracle Database uses locks to control concurrent access to data. A lock is a mechanism that prevents destructive interaction between transactions accessing a shared resource. Locks help ensure data integrity while allowing maximum concurrent access to data.
2.Data Consistency:In Oracle Database, each user must see a consistent view of the data, including visible changes made by a user's own transactions and committed transactions of other users. For example, the database must not permit a dirty read, which occurs when one transaction sees uncommitted changes made by another concurrent transaction.
Oracle Database Server
An Oracle database server consists of a database and at least one database instance
1.Database :A database is a set of files, located on disk, that store data. 2.Database instance:An instance is a set of memory structures that manage database files.
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Chapter 10 - Multimedia Services
Multimedia Services offered Circuit Switched Telephone Networks
1. Fixed and Mobile Telephony 2. Video Telephony 3. Voice Mail 4. Fax 5. Video Conferencing 6. Entertainment/Video on Demand 7. Access to Internet
Packet Switched Internet
1. E-mail/File Transfer 2. Multimedia Mail 3. Video Telephony/Video Conferencing/Internet Phone 4. E-commerce
Broadcast Networks/Satellite and Terrestrial
1. Analog and Digital Audio/Radio and TV Broadcast 2. Interactive TV 3. Video/Movie on Demand
Cable Networks 1. Analog and Digital Audio and TV 2. CD, Video/Audio on Demand/Interactive TV 3. Access to Internet/PSTN
ISDN
1. Digital Telephony/Fax 2. Video Telephony and Conferencing 3. LAN Interconnection 4. Access to Internet
BSNL Multimedia Services
IN Services offered Free Phone Service (FPH)
India Telephone Card (Prepaid card)
Account Card Calling (ACC)
Virtual Private Network (VPN)
Tele-voting
Premium Rae Service (PRM)
Universal Access Number (UAN)
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FLPP (Fixed Line Pre-Paid) Service enables a subscriber to make calls from a prepaid
account linked to his telephone number.
There can be four types of FLPP accounts namely PCO FLPP Account,
PCO Local FLPP Account,
General FLPP Prepaid Account and
General FLPP Prepaid + Post paid Account
Cell One Voice Mail Service ensures that the customers never miss their calls even when
their phone is busy, switched off, out of coverage, or the customer is simply too busy to
take the call.
SMS is 160 character length including spaces, punctuation and special characters.
"PRBT services" means the Personalized Ring Back Tone services. PRBT is a subscriber
feature which provides a subscriber the capability/ flexibility to customize the ring back
tone by substituting the traditional ring back tone with an audio content
CLIP (Caller Line Identification Presentation): enables you to view the number of the calling person when you receive a call
CLIR (Call Line Identification Restriction): enables you to block presentation of your
own number on a called person's phone
Web hosting is a service that allows users to post Web pages to the Internet. The Web Hosting Services of BSNL has been launched and are being hosted presently through web servers located at New Delhi and Bangalore
Universal Personal Number (UPN) :A subscriber to this service can receive or make calls
using his Universal Personal Number from any BSNL phone
Tele voting is a service by which a telephone subscriber can indicate his opinion on any matter by dialing an IN number of the service subscriber followed by a single digit for the opinion. This service is very useful where large numbers of TV programs are operating incentive schemes to increase/retain their viewers
eTracK :An innovative on-line tracking system powered by BSNL to manage fleets comprising of trucks, car carriers, trailers, tankers, containers or vehicles moving hazardous and specially explosive chemicals etc
Subscriber dialed INMARSAT Services :from Shore to Ship, Ship to Shore and Ship to
Ship in Indian region are operational in the BSNL Network
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Chapter 11 - E-Governance/E-Commerce/E-Medicine
E-governance may be defined as delivery of government services and information to the public using electronic means The term e-Governance refers to the process of using information technology for automating both the internal operations of the government and its external interactions with citizens and other businesses
The main focus centers of E-Governance should be
i. The Development of Cyber Laws ii. The Liberalization of Telecommunications iii. Plans for e-Governance iv. Plans for the Development of Community e-Centers v. The Deployment of Community e-Centers vi. Instances of Public Feedback to statements of direction, Draft Legislation and so on vii. Websites of Government Agencies, particularly if these offer value beyond a public relation image
The development of e-Governance includes Publishing Interaction Transaction
Phases of E-Governance
Phase I Presence This first phase calls for making the intentions and objectives of the government
known. With this first phase, the very critical task of building the infrastructure, such as telecommunications would be undertaken.
Phase II Interaction This phase would allow for basic interaction with the government.The task of
building the underlying infrastructure would have to be sustained through these
stages, allowing for rapid implementation of advanced applications as endorsed by
the consequent phases.
Phase III Transaction This phase onwards would signify direct interaction of the government and
relevant entities Phase IV Transformation This final phase would strive to achieve the true vision of e-Governance.
A strategy consists of plans that translate the vision into SMART (Simple, Measurable, Accountable, Realistic & Time-related) projects.
A good approach towards implementation of e-governance is to combine short-term
steps (projects) and long-term goals (vision).
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Accentor has defined an approach to implement e-governance projects: Thinking big, start small and scale fast.
Factors for Risk of implementing e-governance.
Political stability: Democracy or dictatorial regime Level of trust in government: perception of service levels The importance of government identity: fragmentation or integration Economic structure: education, agriculture, industry or service Government structure: centralized or decentralized Different levels of maturity: weakest part of the chain determines speed Constituent demand: push or pull
Electronic Commerce: is trading in products or services using computer networks,
such as the Internet. Electronic commerce draws on technologies such as mobile
commerce, electronic funds transfer, supply chain management, Internet marketing, online
transaction processing, electronic data interchange (EDI), inventory management systems,
and automated data collection systems. Eg of E-Commerce websites : Flipkart,Amazon etc
E-Education or E-Learning is the use of electronic educational technology in learning
and teaching.
E-Medicine: is an online clinical medical knowledge base showing whole directory of
medicines
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Abbrievations BISP BSNL Information Security Policy DoS Denial-of-service attack HTTP Hyper Text Transfer Protocol HTML Hyper Test Markup Language SI System Integrator BPR Business Process Re-engineering FICO Financial Accounting & Controlling HCM Human Capital Management MM Material Management PM Plant Maintenance S&D Sales & Distribution PS Project System REM Real Estate & Management T-Codes Transaction Code ERP Enterprise Resource Planning ESS Employee Self Service SaaS Software as a Service PaaS Platform as a Service IaaS Infrastructure as a Service WWW World Wide Web ISP Internet Service Provider URL Universal Resource Locator DOM Document Object Model XML Extensible Markup Language OSI Open Systems Interconnection LLC Logical Link Control NIC Network Interface Card MAN metropolitan area networks LAN local area networks WAN Wide Area network
CSMA/CD Carrier-sense multiple access with collision detection
DBMS Database Management System
RDBMS Relational Database Management System
SQL Structured Query Language