Security attack--any action that compromises the security of information (In simple terms, attempted to cause damage)
Security Mechanism-- It is a mechanism that is designed to
from security attack
Security Service--makes use of one or more security mechanism
List example of open shop operating system?
Hey! I thought there is an answer here..
I expected too much.
What are the main characteristics of a network operating system?
Characteristics of a network operating system:
What is a computer stub in operating system?
A small software routine placed into a program that provides a common function. Stubs are used for different reasons. For example, a stub might be installed in a client computer, and a counterpart installed on a server, where both are required to resolve some protocol. For example in a remote procedure call (RPC) Stubs are compiled and linked with the client application, instead of containing the actual code that implements the remote procedure. The stub contains just enough code to allow it to be compiled and linked with the rest of a program. Stubs are often used as placeholders for a routine.
What is process control block in operating system?
All of the information needed to keep track of a process when switching is kept in a data package called process control block.s
A PCB is a data structure in the operating system kernel containing the information needed to manage a particular process.
The PCB is the manifestation of a process in an operating system,
Why dinosaur in operating system book?
Because the operating system concepts are as huge as a dinosour.. :)
What operating systems can be installed on Mini-ITX motherboards?
Operating systems are not installed on motherboards. Operating systems are installed on storage media or in some kind of memory including read only memory, which can be part of motherboard.
The standard operating systems that work on most Personal Computer motherboards, that include an Intel compatible CPU, includes versions of Microsoft Windows, Linux, Oracle Solaris and other version of unix,
supervisors
P&id
all of the above
Operating system as resource manager?
This is an alternate view about the services performed by the OS. The OS system provides an orderly and controlled allocation of the processors, memories and I/O devices. When a computer has multiple users the need for managing and protecting the memory, I/O devices and other devices is greater. Thus the primary task of OS is to keep track of who is using which resource, to grant resource requests, to mediate conflicting requests from different programs etc. Resource management includes multiplexing resources in two ways - "in time" and "in space". (i)When a resource is time multiplexed different programs or different users gets their turn to use that resource. eg: Printer. (ii)When a resource is space multiplexed instead of taking turns, the resource is shared among them, ie each one gets a part of the resource. eg: Sharing main memory, hard disk etc.
Properties of Interactive operating system?
An operating system that allows users to run interactive programs. Pretty much all operating systems that are on PCs are interactive OS's
What are the circumstances of user level thread better than kernel level thread?
There are two distinct models of thread controls, and they are user-level threads and kernel-level threads. The thread function library to implement user-level threads usually runs on top of the system in user mode. Thus, these threads within a process are invisible to the operating system. User-level threads have extremely low overhead, and can achieve high performance in computation. However, using the blocking system calls like read(), the entire process would block. Also, the scheduling control by the thread runtime system may cause some threads to gain exclusive access to the CPU and prevent other threads from obtaining the CPU. Finally, access to multiple processors is not guaranteed since the operating system is not aware of existence of these types of threads. On the other hand, kernel-level threads will guarantee multiple processor access but the computing performance is lower than user-level threads due to load on the system. The synchronization and sharing resources among threads are still less expensive than multiple-process model, but more expensive than user-level threads. Thus, user-level thread is better than kernel level thread.
Describe two kernel data structures in which race conditions are possible?
A race condition can occur where a resource that was being waited upon by two data structures/processes is released and both processes try to access it simultaneously. It can also happen where the processor has to assign a unique process ID to two processes that have created at the same time.
What is the difference between parity and non-parity memory?
Non-parity memory is memory without parity. Parity memory is memory with extra bits, sometimes one, sometimes more, that accompany the word. These extra parity bits are generated to a known value, typically to make the total number of bits on that word even or odd. When the word is retrieved, the parity bits are compared against what they should be. If they are different, then one or more of the bits in the original word or in the parity bits must have changed. This is an error condition that can be trapped. In a multiple parity bit system, the calculation of the bits allows not only for the detection of a changed bit, but also for the identification of which bit changed. This is known as ECC parity, or Error-Correcting-Code. Often, you can detect and correct any one bit error, and you can detect, but not correct, any two bit error. Since random bits changes are rare, those that do occur are usually one bit errors, making ECC parity valuable for high reliability systems such as servers.
What are the duties of a stenographer?
Stenographers transcribe proceedings, usually in the legal or medical areas. They must learn to use abbreviated language so they can transcribe verbal proceedings rapidly. They must also be able to proofread their transcriptions.
This coding system is designed to support international languages like Chinese and Japanese?
unicode or ansic
i would say it is due to the lack of processing power, memory and storage capabilties of the handheld system in comparison to that of a PC, the Operating system will be comparable to that of older PC operating systems developed for less powerful computers.
Lots of people say that Linux is the best because it wont get so easily overloaded.
Difference between user view and system view of operating system?
User view: 1) the user view of the computer system varies by the interface being used.
System view: 1)the operating system is a program that is most intimate with computer h/w.
User view: 2)The OS is designed for "ease of use" some attention paid to none paid resource utilization.
System view: 2)we can view an os is resource allocator. The os as act as the manager of the system.
User view: 3) Some user sit at a terminal connected to mainframe or minicomputer. User share resources & may exchange information. That is designed for resource utilization.
System view: 3)os was exist because they are reasonable way to solve the problems at creating a usable Computer system. The goal of pc is to execute user program and make solving problems easier.
Mac OS X is one of the major releases of operating systems from Apple Inc. It features a low level Mach_kernel, underlying Unix OS, a 3D graphical user interface. Mac OS X can only be installed on computers made by Apple Inc. Recent versions of Mac OS X include: Mac OS X 10.3 Panther, Mac OS X 10.4 Tiger, Mac OS X 10.5 Leopard, Mac OS X 10.6 Snow Leopard. Starting in Mac OS 10.5 an automatic backup utility called Time Machine is available.
The current version is Mac OS X 10.10 and an early release version of Mac OS X 10.11 is available to install.
1.Determine what operating system it uses. Finding out what operating system your laptop uses will let you know what key combo (such as "Ctrl+Alt+Delete") can exit you from usage and trigger a reboot or shutdown.
2.Try and reboot using the operating system. Attempt to use the key combination that will allow you to exit from the operating system and restart the laptop. Be patient, as it may take some time if it has locked up. 3. Hold down the power button. If the operating system's answer to the rebooting will not work, find and hold down the power button of the laptop. This should cause the device to shut itself off. You'll have to press the power button again to power it back on, completing the reboot. 4. Unplug from the wall and remove the battery. If restarting via the operating system and the power button do not work, unplug the laptop from the wall outlet, and remove the battery from the laptop. This will cause it to power off immediately. 5. Allow time to reboot. Give the laptop time to cool down before you power it back on if you had to do this manually. A few seconds should do unless you have additional problems.