Everything is displayed in form a reactangular window. Read More

Main component of operating system are kernel and shell shell is a interface between application program and kernel whenever application program wants some work to be done It contacts kernel and kernel inturn perform work with the help of device... Read More

Structural class: The structural class is important to the system administrator in that it is the only type from which new Active Directory objects are created. Structural classes are developed from either the modification of an existing structural... Read More

Unix and Windows use completely different paradigms for run-time loading of code. Before you try to build a module that can be dynamically loaded, be aware of how your system works. In Unix, a shared object (.so) file contains code to be used by... Read More

Multi programming: Multiprogramming is the technique of running several programs at a time using timesharing. It allows a computer to do several things at the same time. Multiprogramming creates logical parallelism. The concept of multiprogramming... Read More

The thread library function performs the following actions to context switch between user level threads Copy all live registers to Thread control Block (TCB) Restore the state of the thread to run next i.e (copy the values of live registers from (TCB... Read More

Security-related modifications are replicated within a site immediately. These changes include account and individual user lockout policies, changes to password policies, changes to computer account passwords, and modifications to the Local Security... Read More

->The concept of a logical address space that is bound to a separate physical address space is central to proper memory management. Logical address ? generated by the CPU; also referred to as virtual address. Physical address ? address seen by... Read More

->Ensure that the system will never enter a deadlock state. ->Allow the system to enter a deadlock state and then recover. ->Ignore the problem and pretend that deadlocks never occur in the system; used by most operating systems, including ... Read More

Each device driver can control one or more I/O devices, but a device driver can also do things not related to a specific device, such as encrypting a data stream or even just providing access to kernel data structures. Device drivers are not part of... Read More

Winlogon.exe is also responsible for all user logins. The actual login dialog is handled by a separate program in msgina. dll to make it possible for third parties to replace the standard login with face print identification or something else other... Read More

Paging is solution to external fragmentation problem which is to permit the logical address space of a process to be noncontiguous, thus allowing a process to be allocating physical memory wherever the latter is available. Read More

Both Windows XP and 2000 come in diffrent flavours..likefor XP u have Home,professional and Enterprise Edition. With 2000 u have professional,Server/s as it professional is more like client pc in Client server Archietecture..can also be used for... Read More

The cache manager keeps the most recently used disk blocks in memory to speed up access to them in the event that they are needed again. Its job is to figure out what which blocks are probably going to be needed again and which ones are not. It is... Read More

Given example is correct. ans:WIN NT,minx. Read More

SAM is generally called as Security account manager. The SAM subkey contains the user names, groups, passwords, and other account and security information needed for logging in. The SECURITY sub key contains general security policy information, such... Read More

The TCB(Transmission and controlling Buses) used to control the flow of tranmittion and controlling data in the computer systems Read More

When a process requests an available resource, system must decide if immediate allocation leaves the system in a safe state ->System is in safe state if there exists a safe sequence of all processes. ->Sequence <P1, P2? Pn> is safe if for... Read More

Process system time (turn around time) = process cpu time + process waiting time Read More

Dynamic Loading: ->Routine is not loaded until it is called -> Better memory-space utilization; unused routine is never loaded. ->Useful when large amounts of code are needed to handle infrequently occurring cases. ->No special support... Read More

A virtual memory is hardware technique where the system appears to have more memory that it actually does. This is done by time-sharing, the physical memory and storage parts of the memory one disk when they are not actively being used. Read More

The Active Directory replaces them. Now all domain controllers share a multimaster peer-to-peer read and write relationship that hosts copies of the Active Directory. Read More

->Hardware device that maps virtual to physical address. In MMU scheme, the value in the relocation register is added to every address generated by a user process at the time it is sent to memory. ->The user program deals with logical addresses... Read More

A page fault occurs when an access to a page that has not been brought into main memory takes place. The operating system verifies the memory access, aborting the program if it is invalid. If it is valid, a free frame is located and I/O is... Read More

Active Directory is a network-based object store and service that locates and manages resources, and makes these resources available to authorized users and groups. An underlying principle of theActive Directory is that everything is considered an... Read More

The need for multi-tasking operating systems including Unix, Linux, Windows xp , 2000 etc. in a single user machines is for simultaneous access to many applications. For example while using internet explorer wants attach some document file(.doc) it... Read More

Process Termination: ->Abort all deadlocked processes. ->Abort one process at a time until the deadlock cycle is eliminated. ->In which order should we choose to abort? Priority of the process. How long process has computed, and how much... Read More

TASK : A Particular Work to be Done is known as TASK PROCESS : one or more PROCESS will be required to complete a task. Read More

A hard real-time system guarantees that critical tasks complete on time. This goal requires that all delays in the system be bounded from the retrieval of the stored data to the time that it takes the operating system to finish any request made of it... Read More

Main memory: ? only large storage media that the CPU can access directly. Secondary storage: ? extension of main memory that provides large nonvolatile storage capacity. Read More

->Selects from among the processes in memory that are ready to execute, and allocates the CPU to one of them. ->CPU scheduling decisions may take place when a process: 1.Switches from running to waiting state. 2.Switches from running to ready... Read More

DRAM is the Hershey's chocolate of readable/writable memory: it's not the best, but it's cheap, does the job, and is available almost everywhere you look. DRAM data resides in a cell made of a capacitor and a transistor. The... Read More

A real time process is a process that must respond to the events within a certain time period. A real time operating system is an operating system that can run real time processes successfully Read More

When an application that ran on an earlier legacy version of Windows cannot be loaded during the setup function or if it later malfunctions, you must run the compatibility mode function. This is accomplished by right-clicking the application or setup... Read More

NTFS writes a file marked for compression to disk; it examines the first blocks in the file, irrespective of how many runs they occupy. It then runs a compression algorithm on them. If the resulting data can be stored in 15 or fewer blocks, the... Read More

When DC promotion occurs with an existing forest, the Active Directory Installation Wizard contacts an existing DC to update the directory and replicate from the DC the required portions of the directory. If the wizard fails to locate a DC, it... Read More

The Global Catalog authenticates network user logons and fields inquiries about objects across a forest or tree. Every domain has at least one GC that is hosted on a domain controller. In Windows 2000, there was typically one GC on every site in... Read More

Starvation: Starvation is a resource management problem where a process does not get the resources it needs for a long time because the resources are being allocated to other processes. Aging: Aging is a technique to avoid starvation in a scheduling... Read More

Semiconductor memories are of two types: RAM (random access memory) and ROM (read only memory). RAM is a read/write memory. Information can be written into and read from a RAM. It is volatile memory. It stores information so long as power supply is... Read More

Windows 200o consists of two major pieces: the operating system itself, which runs in kernel model, and the environment subsystems, which runs in user mode. The kernel is a traditional kernel in the sense that it handles process management, memory... Read More

Waiting state Read More

Windows Server 2003 provides a command called Repadmin that provides the ability to delete lingering objects in the Active Directory. Read More

Deadlock can arise if four conditions hold simultaneously. Mutual exclusion: only one process at a time can use a resource. Hold and wait: a process holding at least one resource is waiting to acquire additional resources held by other processes. No... Read More

Throughput ? number of processes that complete their execution per time unit Turnaround time ? amount of time to execute a particular process Waiting time ? amount of time a process has been waiting in the ready queue Response time ? amount of time... Read More

For the conventional time ?shared processes, Linux uses a prioritized, credit-based algorithm. Each process possesses a certain number of scheduling credits; when a new task must be chosen to run, the process with most credits is selected. Every time... Read More

An interpreter reads one instruction at a time and carries out the actions implied by that instruction. It does not perform any translation. But a compiler translates the entire instructions. Read More

Demand Paging: Demand paging is the paging policy that a page is not read into memory until it is requested, that is, until there is a page fault on the page. Page fault interrupt: A page fault interrupt occurs when a memory reference is made to a... Read More

Micro-Kernel: A micro-kernel is a minimal operating system that performs only the essential functions of an operating system. All other operating system functions are performed by system processes. Monolithic: A monolithic operating system is one... Read More

->Interrupt transfers control to the interrupt service routine generally, through the interrupt vector, which contains the addresses of all the service routines. ->Interrupt architecture must save the address of the interrupted instruction. -... Read More

Recall that paging is implemented by breaking up an address into a page and offset number. It is most efficient to break the address into X page bits and Y offset bits, rather than perform arithmetic on the address to calculate the page number and... Read More

Segments can be of different lengths, so it is harder to find a place for a segment in memory than a page. With segmented virtual memory, we get the benefits of virtual memory but we still have to do dynamic storage allocation of physical memory.... Read More

Consider any system where people use some kind of resources and compete for them. The non-computer examples for preemptive scheduling the traffic on the single lane road if there is emergency or there is an ambulance on the road the other vehicles... Read More

->When, and how often, to invoke depends on: How often a deadlock is likely to occur? How many processes will need to be rolled back? ->If detection algorithm is invoked arbitrarily, there may be many cycles in the resource graph and so we... Read More

->Dispatcher module gives control of the CPU to the process selected by the short-term scheduler; this involves: Switching context Switching to user mode Jumping to the proper location in the user program to restart that program Dispatch latency ?... Read More

Used for booting SCSI devices when no SCSI BIOS is available Read More

Process is some job or task which is running in background. while a thread is a single line of execution in a programs , so many threads can be there in a program. Read More

Question : What is active directory?How it works? What is dns?How it works? What is dhcp?How it works? What is ias?How it works? Answers: AD is a hierarchical database which includes objects like Users,Computers etc. DNS is ... Read More

An address on a paging system is a logical page number and an offset. The physical page is found by searching a table based on the logical page number to produce a physical page number. Because the operating system controls the contents of this... Read More

Operating system controls and coordinates the use of the hardware among the various applications programs for various uses. Operating system acts as resource allocator and manager. Since there are many possibly conflicting requests for resources the... Read More

Virtual memory is double of RAM.As per question RAM is 128MB.so virtual memory is 256MB. Read More

A semaphore is created using the CreateSemaphore API function, which can initialize it to a given value and define a maximum value as well. Semaphores are kernel objects and thus have security descriptors and handles. The handle for a semaphore can... Read More

Scheduling is the activity of the deciding when process will receive the resources they request. FCFS: --- FCSFS stands for First Come First Served. In FCFS the job that has been waiting the longest is served next. Round Robin Scheduling: ---Round... Read More

HAL is a thin layer below the Kernel. The job of the hardware abstraction layer is to present the rest of the operating system with abstract hardware devices. These devices are presented in the form of machine-independent services that the rest of... Read More

The other kind of kernel objects are dispatcher objects. These include semaphores, mutexes, events, waitable timers, and other objects where threads can wait on. The reason that these have to be handled in the kernel is that they are intimately... Read More

Objects have a structure. Each object contains a header with certain information common to all objects of all types. The fields in this header include the objects name, the object directory in which it lives in objects space, security information and... Read More

The I/O manager is also closely associated with the power manager. The power manager can put the computer into any of the six states, they are 1)Fully operational 2) CPU power reduced, RAM and cache on, instant wake up 3)CPU and RAM on, CPU cache off... Read More

An interesting feature of windows 2000 is its support for dynamic disks. These disks may span multiple partitions and even multiple disks and may be reconfigured on the fly, without even having to reboot. In this way, logical volumes are no longer... Read More

Each NTFS volume contains files, directories, bitmaps, and other data structures. Each volume is organized as a linear sequence of blocks, with the block size being fixed for each volume and ranging from 512 bytes to 64 KB, depending on the volume... Read More

A microcontroller is by definition a is a computer on a chip. It includes all the necessary parts (including the memory) all in one IC. You just need to apply the power (and possibly clock signal) to that device and it starts executing the program... Read More

Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. As the microprocessor processes data, it looks first in thecache memory and if it finds the data there (from a previous... Read More

Specification of the task Design of algorithms Implementation (coding) Testing and debugging Maintenance and evolution of the system Obsolescence Read More

Hard disk is the secondary storage device, which holds the data in bulk, and it holds the data on the magnetic medium of the disk.Hard disks have a hard platter that holds the magnetic medium, the magnetic medium can be easily erased and rewritten,... Read More

A real time operating system has well defined fixed time constraints. Process must be done within the defined constraints or the system will fail. An example is theoperating system for a flight control computer or an advanced jet airplane. Often ... Read More

THere is two solutions: 1. Restore from last back. 2. User Recycler folder. Start-->RUN-->type c:recycler --> type FTYPE Read More

Question : I am using Windows 2000 OS. At DOS prompt while I am issuing CD command to switch to an existing directory (eg. appserver) it is throwing error 'Invalid directory'. Would appreciate if anybody have an idea how to resolve it... Read More

Outlook Express is a no-cost, basic e-mail program that is included with Microsoft Internet Explorer. Outlook Express stores contacts in a Microsoft Windows? Address Book file with an extension of .wab. The name of the file is based on your Windows... Read More

Question : Difference between:- 1. TCP and RDP 2. DOMAIN and OU 3. DOMAIN CONTROLLER and GLOBAL CATALOG Answers: Every Global Catalog Server is a DC, But every DC is not GC. GC holds partial attributes of the domain... Read More

In short dump terminals are the terminals which are conncted with a centralized CPU and lack individual CPUs. Read More

There is a freeware available called as explore2fs.exe which will show all the linux partitions on windows desktop Read More

The Boot.ini file is set as read-only, system, and hidden to prevent unwanted editing. To change the Boot.ini timeout and default settings, use the System option in Control Panel from the Advanced tab and select Startup. Read More

Start ?> Control Panel ?> Network and Internet Connections ?> Network Connections. Read More

Fragmentation occurs in a dynamic memory allocation system when many of the free blocks are too small to satisfy any request. External Fragmentation: External Fragmentation happens when a dynamic memory allocation algorithm allocates some memory... Read More

How to satisfy a request of size n from a list of free holes? First-fit: Allocate the first hole that is big enough. Best-fit: Allocate the smallest hole that is big enough; must search entire list, unless ordered by size. It produces the smallest... Read More

Organizations that operate on radically different bases may require separate trees with distinct namespaces. Unique trade or brand names often give rise to separate DNS identities. Organizations merge or are acquired and naming continuity is desired... Read More

Four types of authentication are used across forests: (1) Kerberos and NTLM network logon for remote access to a server in another forest; (2) Kerberos and NTLM interactive logon for physical logon outside the user?s home forest; (3) Kerberos... Read More

When an account is created, it is given a unique access number known as a security identifier (SID). Every group to which the user belongs has an associated SID. The user and related group SIDs together form theuser account?s security token, which... Read More

No. If you delete a user account and attempt to recreate it with the same user name and password, the SID will be different. Read More

Credential Management feature of Windows Server 2003 provides a consistent single sign-on experience for users. This can be useful for roaming users who move between computer systems. The Credential Management feature provides a secure store of... Read More

"Save password as encrypted clear text" must be selected on User Properties Account Tab Options, since the Macs only store their passwords that way. Read More

Dial-in, VPN, dial-in with callback. Read More

Processor:--A processor is the part a computer system that executes instructions .It is also called a CPU Assembler: -- An assembler is a program that takes basic computer instructions and converts them into a pattern of bits that the computer'... Read More

It is called light weight process to emphasize the fact that a thread is like a process but is more efficient and uses fewer resources( n hence "lighter")and they also share the address space. Read More

The purpose of the lexical analyzer is to partition the input text, delivering a sequence of comments and basic symbols. Comments are character sequences to be ignored, while basic symbols are character sequences that correspond to terminal symbols... Read More

Thrashing is caused by under allocation of the minimum number of pages required by a process, forcing it to continuously page fault. The system can detect thrashing by evaluating the level of CPU utilization as compared to the level of... Read More

Address binding of instructions and data to memory addresses can happen at three different stages Compile time: If memory location known a priori, absolute code can be generated; must recompile code if starting location changes. Load time: Must... Read More

When a thread is created the threads does not require any new resources to execute the thread shares the resources like memory of the process to which they belong to. The benefit of code sharing is that it allows an application to have several... Read More

Deadlock is a situation where a group of processes are all blocked and none of them can become unblocked until one of the other becomes unblocked. The simplest deadlock is two processes each of which is waiting for a message from the other. Read More

Switching the CPU to another process requires saving the state of the old process and loading the saved state for the new process. This task is known as a context switch. Context-switch time is pure overhead, because the system does no useful work... Read More

At the bottom of the hierarchy are the entries, called values, which contain the information. Each value has three parts a name, a type, and the data. The name is just a Unicode string, often default if the directory contains only one value. The type... Read More

Control objects are those objects that control the system, including primitive process objects, interrupt objects, and two somewhat strange objects called DPC and APC. A DPC object is used to split off the non time critical part of an interrupt... Read More

diskcopy Java Thread States Read More

OS Drive windowssystem32driversetcservices.file Read More

Active Directory Domains and Trusts Manager, Active Directory Sites and Services Manager, Active Directory Users and Group Manager, Active Directory Replication (optional, available from the Resource Kit), Active Directory Schema Manager (optional,... Read More

Hard real-time systems ? required to complete a critical task within a guaranteed amount of time. Soft real-time computing ? requires that critical processes receive priority over less fortunate ones. Read More

Sockets are like pipes, except that they normally connect processes on different machines. One process writes to a socket and another one on a remote machine read from it. Sockets can also be used to connect processes on the same machine, but since... Read More

These functions periodically check to determine clean pages. If there are not, they take pages from the top of the modified list, write them back to disk, and then move them to the standby list. The former handles writes to mapped files and the... Read More

Distribute the computation among several physical processors. Loosely coupled system ? each processor has its own local memory; processors communicate with one another through various communications lines, such as high-speed buses or ... Read More

Win ME, Win 98, 2000, XP. Note, however, that you cannot upgrade from ME and 98 to Windows Server 2003. Read More

Winkey opens or closes the Start menu. Winkey + BREAK displays the System Properties dialog box. Winkey + TAB moves the focus to the next application in the taskbar. Winkey + SHIFT + TAB moves the focus to the previous application in the taskbar.... Read More