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Big Data Analytics - Data Analyst A data analyst has reporting-oriented profile, having experience in extracting and analyzing data from traditional data warehouses using SQL. Their tasks are normally either on the side of data storage or in reporting general business results. Data warehousing is by no means simple, it is just different to what a data scientist does. Many organizations struggle hard to find competent data scientists in the market. It is however a good idea to select prospective data analysts and teach them the relevant skills to become a data scientist. This is by no means a trivial task and would normally involve the person doing a master degree in a quantitative field, but it is definitely a viable option. The basic skills a competent data analyst must have are listed below − Business understanding SQL programming Report design and implementation Dashboard development Big Data Analytics - Data Scientist The role of a data scientist is normally

Context of Cryptography Cryptology, the study of cryptosystems, can be subdivided into two branches −     1.Cryptanalysis     2.Cryptography, Description: Cryptography Types What is Cryptography? Cryptography is the art and science of making a cryptosystem that is capable of providing information security. Cryptography deals with the actual securing of digital data. It refers to the design of mechanisms based on mathematical algorithms that provide fundamental information security services. You can think of cryptography as the establishment of a large toolkit containing different techniques in security applications. What is Cryptanalysis? The art and science of breaking the cipher text is known as cryptanalysis. Cryptanalysis is the sister branch of cryptography and they both co-exist. The cryptographic process results in the cipher text for transmission or storage. It involves the study of cryptographic mechanism with the intention to break them. Cryptanalysi

Cloud Computing provides us means of accessing the applications as utilities over the Internet. It allows us to create, configure, and customize the applications online. What is Cloud? The term Cloud refers to a Network or Internet. In other words, we can say that Cloud is something, which is present at remote location. Cloud can provide services over public and private networks, i.e., WAN, LAN or VPN. Applications such as e-mail, web conferencing, customer relationship management (CRM) execute on cloud. What is Cloud Computing? Cloud Computing refers to manipulating, configuring, and accessing the hardware and software resources remotely. It offers online data storage, infrastructure, and application.                                            Cloud Computing Cloud computing offers platform independency, as the software is not required to be installed locally on the PC. Hence, the Cloud Computing is making our business applications mobile and collaborative. Basi

Cloud computing is based on service models. These are categorized into three basic service models which are - Infrastructure-as–a-Service (IaaS) Platform-as-a-Service (PaaS) Software-as-a-Service (SaaS) Anything-as-a-Service (XaaS) is yet another service model, which includes Network-as-a-Service, Business-as-a-Service, Identity-as-a-Service, Database-as-a-Service or Strategy-as-a-Service. The Infrastructure-as-a-Service (IaaS) is the most basic level of service. Each of the service models inherit the security and management mechanism from the underlying model, as shown in the following diagram: Cloud Computing Service Models 1.INFRASTRUCTURE-AS-A-SERVICE (IAAS) IaaS provides access to fundamental resources such as physical machines, virtual machines, virtual storage, etc. 2.PLATFORM-AS-A-SERVICE (PAAS) PaaS provides the runtime environment for applications, development and deployment tools, etc. 3.SOFTWARE-AS-A-SERVICE (SAAS) SaaS model allows to use software application

There are certain technologies working behind the cloud computing platforms making cloud computing flexible, reliable, and usable. These technologies are listed below: Virtualization Service-Oriented Architecture (SOA) Grid Computing Utility Computing Virtualization Virtualization is a technique, which allows to share single physical instance of an application or resource among multiple organizations or tenants (customers). It does this by assigning a logical name to a physical resource and providing a pointer to that physical resource when demanded. Cloud Computing Virtualization Model The Multitenant architecture offers virtual isolation among the multiple tenants. Hence, the organizations can use and customize their application as though they each have their instances running. Service-Oriented Architecture (SOA) Service-Oriented Architecture helps to use applications as a service for other applications regardless the type of vendor, product or technology. Therefor

Cloud Computing architecture comprises of many cloud components, which are loosely coupled. We can broadly divide the cloud architecture into two parts: Front End Back End Each of the ends is connected through a network, usually Internet. The following diagram shows the graphical view of cloud computing architecture: Cloud Computing Architecture   Front End The front end refers to the client part of cloud computing system. It consists of interfaces and applications that are required to access the cloud computing platforms, Example - Web Browser. Back End The back End refers to the cloud itself. It consists of all the resources required to provide cloud computing services. It comprises of huge data storage, virtual machines, security mechanism, services, deployment models, servers, etc. Note It is the responsibility of the back end to provide built-in security mechanism, traffic control and protocols. The server employs certain protocols known as middleware, which help

Cloud Computing has its applications in almost all the fields such as business, entertainment, data storage, social networking, management, entertainment, education, art and global positioning system, etc. Some of the widely famous cloud computing applications are discussed here in this tutorial: Business Applications Cloud computing has made businesses more collaborative and easy by incorporating various apps such as MailChimp, Chatter, Google Apps for business, and Quickbooks.        1        MailChimp    It offers an e-mail publishing platform. It is widely employed by the businesses to design and send their e-mail campaigns. 2        Chatter    Chatter app helps the employee to share important information about organization in real time. One can get the instant feed regarding any issue. 3        Google Apps for Business    Google offers creating text documents, spreadsheets, presentations, etc., on Google Docs which allows the business users to shar

Various Cloud Computing platforms are available today. The following table contains the popular Cloud Computing platforms: 1         Salesforce.com This is a Force.com development platform. This provides a simple user interface and lets users log in, build an app, and push it in the cloud. 2        Appistry The Appistry's CloudIQ platform is efficient in delivering a runtime application. This platform is very useful to create scalable and service oriented applications. 3        AppScale The AppScale is an open source platform for App Engine of Google applications. 4        AT&T The AT&T allows access to virtual servers and manages the virtualization infrastructure. This virtualization infrastructure includes network, server and storage. 5        Engine Yard The Engine Yard is a rails application on cloud computing platform. 6        Enomaly Enomaly provides the Infrastructure-as-a-Service platform. 7        FlexiScale The FlexiScale

Operating system? operating system is an interface between user and computer hardware. the hardware of the computer cannot understand the human readable language as it works on binaries eg 0 's and 1 's .also it is very tough for humans to understand the binary language,in such case we need an interface which can translate human language to hardware vice-versa for effective communication. Types of operating system? single user-- single tasking operating system single user-- multitasking operating system multi user-- multitasking operating system single user--single tasking operating system in this type of operating system only one user can login into the system and can perform only one task at the time. EG:MS-DOS single user--multitasking operating system   this type of operating system only one user can login into the system and can perform multiple task at the time.browsing internet while playing songs. EG:WINDOWS -98,XP,VISTA,7,8,10 etc.

The transmission media is nothing but the physical media over which communication takes place in computer networks. Magnetic Media One of the most convenient way to transfer data from one computer to another, even before the birth of networking, was to save it on some storage media and transfer physical from one station to another. Though it may seem old-fashion way in today’s world of high speed internet, but when the size of data is huge, the magnetic media comes into play. For example, a bank has to handle and transfer huge data of its customer, which stores a backup of it at some geographically far-away place for security reasons and to keep it from uncertain calamities. If the bank needs to store its huge backup data then its,transfer through internet is not feasible.The WAN links may not support such high speed.Even if they do; the cost too high to afford. In these cases, data backup is stored onto magnetic tapes or magnetic discs, and then shifted physically at rem

 Some basic services computer network can offer are. Directory Services These services are mapping between name and its value, which can be variable value or fixed. This software system helps to store the information, organize it, and provides various means of accessing it. Accounting In an organization, a number of users have their user names and passwords mapped to them. Directory Services provide means of storing this information in cryptic form and make available when requested. Authentication &and Authorization User credentials are checked to authenticate a user at the time of login and/or periodically. User accounts can be set into hierarchical structure and their access to resources can be controlled using authorization schemes. Domain Name Services DNS is widely used and one of the essential services on which internet works. This system maps IP addresses to domain names, which are easier to remember and recall than IP addresses. Because network operates

Networking engineering is a complicated task, which involves software, firmware, chip level engineering, hardware, and electric pulses. To ease network engineering, the whole networking concept is divided into multiple layers. Each layer is involved in some particular task and is independent of all other layers. But as a whole, almost all networking tasks depend on all of these layers. Layers share data between them and they depend on each other only to take input and send output. Layered Tasks In layered architecture of Network Model, one whole network process is divided into small tasks. Each small task is then assigned to a particular layer which works dedicatedly to process the task only. Every layer does only specific work. In layered communication system, one layer of a host deals with the task done by or to be done by its peer layer at the same level on the remote host. The task is either initiated by layer at the lowest level or at the top most level. If the task is

During initial days of internet, its use was limited to military and universities for research and development purpose. Later when all networks merged together and formed internet, the data useds to travel through public transit network.Common people may send the data that can be highly sensitive such as their bank credentials, username and passwords, personal documents, online shopping details, or confidential documents. All security threats are intentional i.e. they occur only if intentionally triggered. Security threats can be divided into the following categories:   Interruption Interruption is a security threat in which availability of resources is attacked. For example, a user is unable to access its web-server or the web-server is hijacked. Privacy-Breach In this threat, the privacy of a user is compromised. Someone, who is not the authorized person is accessing or intercepting data sent or received by the original authenticated user. Integrity This type of thre

A Network Topology is the arrangement with which computer systems or network devices are connected to each other. Topologies may define both physical and logical aspect of the network. Both logical and physical topologies could be same or different in a same network. Point-to-Point Point-to-point networks contains exactly two hosts such as computer, switches or routers, servers connected back to back using a single piece of cable. Often, the receiving end of one host is connected to sending end of the other and vice-versa. If the hosts are connected point-to-point logically, then may have multiple intermediate devices. But the end hosts are unaware of underlying network and see each other as if they are connected directly. Bus Topology   In case of Bus topology, all devices share single communication line or cable.Bus topology may have problem while multiple hosts sending data at the same time. Therefore, Bus topology either uses CSMA/CD technology or recognizes one host a

Let us go through various LAN technologies in brief: Ethernet Ethernet is a widely deployed LAN technology.This technology was invented by Bob Metcalfe and D.R. Boggs in the year 1970. It was standardized in IEEE 802.3 in 1980. Ethernet shares media. Network which uses shared media has high probability of data collision. Ethernet uses Carrier Sense Multi Access/Collision Detection (CSMA/CD) technology to detect collisions. On the occurrence of collision in Ethernet, all its hosts roll back, wait for some random amount of time, and then re-transmit the data. Ethernet connector is,network interface card equipped with 48-bits MAC address. This helps other Ethernet devices to identify and communicate with remote devices in Ethernet. Traditional Ethernet uses 10BASE-T specifications.The number 10 depicts 10MBPS speed, BASE stands for baseband, and T stands for Thick Ethernet. 10BASE-T Ethernet provides transmission speed up to 10MBPS and uses coaxial cable or Cat-5 twisted pai

Generally, networks are distinguished based on their geographical span. A network can be as small as distance between your mobile phone and its Bluetooth headphone and as large as the internet itself, covering the whole geographical world, Personal Area Network A Personal Area Network (PAN) is smallest network which is very personal to a user. This may include Bluetooth enabled devices or infra-red enabled devices. PAN has connectivity range up to 10 meters. PAN may include wireless computer keyboard and mouse, Bluetooth enabled headphones, wireless printers and TV remotes. Personal Area Network For example, Piconet is Bluetooth-enabled Personal Area Network which may contain up to 8 devices connected together in a master-slave fashion. Local Area Network A computer network spanned inside a building and operated under single administrative system is generally termed as Local Area Network (LAN). Usually,LAN covers an organization’ offices, schools, colleges or universit