Computer Science and IT Professional Knowledge

The basic unit of execution is thread. It splits the program in parts and simultaneously processes all the parts. 

A firewall cannot give protection against internal threats present within the system. It also cannot prevent transfer of virus-infected programs or files.

The command “n>&m” is a redirection command in UNIX. It is used for merging an output from stream n with stream m.

Class is a basic data type in Java. It is used as template for creating object. Each object has its own characteristics and properties.

SHILVL is an environment variable in UNIX which is used to find whether the built-in exit commands end the current session or not and increment by one each time an instance of bash is started.

Stations or workstations are the end devices of a communication network which transfer data to each other using the network.

LAN is sized up to few kilometers. The transmission time in worst case is known in advance using the length. Hence, it is more reliable as compared to others.

Border Gateway Protocol (BGP), Open Shortest Path First (OSPF), Routing Information Protocol (RIP) and Dijkstra are routing protocols, while User Datagram Protocol (UDP) is an internet protocol.

Local variables are defined and initialised inside a method. Instance variables may be declared outside a method and can be accessed only inside that method. Class variables are declared within a class and with static keyword.

Security auditing is the process of evaluating system reports to find whether the system is according to the standard security norms or not. It includes collection of information like user’s access activities, resource access, etc.

Except “do while”, all the others are Java keywords. “do while” is a keyword of C programming language.

Dispatcher is involved in CPU scheduling process. Its functions are to switch context, to switch to user mode and start a different process when another is running.

Transport layer is the fourth layer of the OSI model. It is responsible for segmentation and reassembly of message packets.

Metamorphic virus creates a new virus as it finds the loopholes. However, in each mutation, it rewrites itself, making the detection very complex.

In abstraction of data, only the important information is shown to the user of that data.

The rate of processing of data is called throughput. It gives the system performance in terms of processed information. Response time is the time taken by the CPU to respond to a request.

Service catalogue is the product of service level management. It contains information on all operational services ready for deployment.

“ddd” is a notation in Java which represents octal character.

Configuration management is a discipline applying technical and administrative direction and surrounding veilance to identify and document the functional and physical characteristics of a configuration item.

Except dot net, all others are RDBMS packages. Dot net is a programming language.

Not all viruses can copy themselves. Some mutate to give a completely different virus program. So, it is not one of the phases of a life of a virus.

The compression-decompression as well as encryption-decryption of data is provided by presentation layer.

Conjunction is a C++ operator used for concatenation of two statements. Its symbol is “&&”.

MTTR stands for mean time to repair. It is a part of monitoring a system in which the average of time needed to repair a fault is found. The lower the MTTR, the more efficient is the system.

The first fully transistorised computer was TRADIC.

Handshaking is the process of sharing acknowledgements to transfer data from one system to another when the second device is ready for reception.

OLTP stands for 'on line transaction processing'. In it, normalisation of database is done to facilitate insertion, deletion and updation of data.

For logic coverage, only the logic paths of the system are checked. It is not necessary to execute function.

SQL server is a product of Microsoft.

Resource preemption is the method of deadlock elimination in which some resources are preempted and given to other processes till deadlock circle breaks.

Message passing model facilitates communication by means of reading or writing data in shared regions.

Shortest job first scheduling and priority scheduling are two algorithms used for scheduling. Shortest job first is a special case of priority scheduling.

In multitasking, only one program is executed once, but the switching time from one program to other is so small that it seems that many programs are being executed at the same time.

Digital Subscriber Line (DSL) is a connection used in broadband for providing link between user and network for communication.

The order for DBMS interface is: End user - Application program - SQL - DBMS - OS - Database.

Banker’s algorithm is a resource allocation and deadlock avoidance algorithm.

Loopback address is 127.0.0.1. It is used for software loopback interface of a machine.

Using paging and page stealing leads to a technical problem in which unusually large time is taken for transferring pages to and from a backing store. It is called thrashing.

Encapsulation binds the functions of a program with data. It is a characteristic feature of object oriented programming language. The encapsulated object behaves as if it is a black box.

Digital signature is basically a technique to ensure the authenticity and integrity of the communicated data.

Configuration Management (CM) observes the physical characteristics of a system and controls the changes to ensure that the changes comply with specified requirements. It includes checking developer’s area, unit test area and integration test area.

The first octal decimal range of class B IP address is 128-191; 190 falls under this range, so it is of class B.

The arrangement of bookmarks can be done by using folders.

C++ provides some basic input/output stream. Cerr is one of such streams used for standard output error.

Drive-by download programs do not take consent before getting downloaded. These are malicious spywares.

Quick sort technique involves choosing a central element which is used to partition data according to the value. Then, both sets are individually processed by continuous partitioning and the required order is obtained.

Gateway is used in network layer. It connects a given network to a significantly different network.

Do while is a looping technique used in C programming, which first executes the statement and then checks the conditions. So, it is exit controlled. While and for are entry controlled.

Power problems arise due to power fluctuations and power failure. Surge suppressor reduces effect of voltage spikes. Line conditioners provide safety against line noise. UPS provides battery backup. 

Software quality factors are the measures to check whether the software created is efficient as well as economic. Some of these factors are: Correctness, Maintainability, Reliability, Reusability, Usability and Portability.