Operating System Articles - Page 144 of 171

The session layer supports establishing, controlling, and eliminating a session or dialogue between the two end frameworks. It generates the session, handles the packets sent back and forth during the session and removes the session. The dialogue type/session type is also defined through half-duplex or full-duplex.The session layer also supports data synchronization and check pointing so that only the information transmitted after the point of failure should be retransmitted in the event of network failure.This layer also governs the dialogue between the two processes by deciding who can send and who can get at what point during the transmission.The session ... Read More

Physical layer is the shortest layer in the model. This layer is feasible for initiating, preserving, and deactivating a physical circuit between two end frameworks.The Physical Layer is vital for transmitting bits from one device to another device. It can change the series of bits into electric signals, light signals, or electromagnetic signals, relying on either the two hubs on a link circuit, fiber-optic circuit, or microwave/radio circuit.Passive hubs, simple active hubs, terminators, couplers, cables, connectors, repeaters, multiplexers, transmitters and receivers are the devices associated with the physical layer.The physical layer situation for the transmission channel and the data link ... Read More

In this post, we will understand the difference between system calls fork and vfork −The ‘fork’ system callIn this system call, the child and parent process have separate memory spaces.The child and parent process are executed simultaneously.This call uses the copy-on-write as alternative.Child process doesn’t have the ability to suspend execution of the parent process in this system call.The page of one process doesn’t get affected by the page of other process.It is more frequently used.No address space is wasted.If the child process alters the page in the address space, it is not visible to the parent process.The ‘vfork’ system ... Read More

In this post, we will understand the difference between microkernel and monolithic kernel −MicrokernelIt is smaller in size.In this kernel, the services are kept in a separate address space.It executes slowly in comparison to monolithic kernel.It can be extended easily.If a service crashes, it effects the working of the microkernel.The code to build a microkernel is large.Examples of microkernel include: QNX, Symbian, L4Linux, Singularity, K42, Integrity, PikeOS, HURD, Minix, Mac OS X, and Coyotos.Monolithic KernelIn monolithic kernel, both user services and kernel services are kept in the same address space.Monolithic kernel is larger than microkernel.It executes quickly in comparison to ... Read More

An operating system acts as a bridge between the hardware and applications. The CPU is that part of the system which handles all the tasks of the system. Sometime such situations arise, when it is required to interrupt the currently running task and take a rapid action. Therefore, in operating system, there are two methods namely interrupt and polling for dealing with such events. In both interrupt and polling, the CPU is paused what it is doing and made to execute an essential task. Both interrupt and polling are quite different from each other in several ways. In this article, ... Read More

Buffering and caching, two important concepts in operating systems, are used to increase the data transmission and processing speed. The most basic difference between buffering and caching is that buffering is used to sync the speed of data transmission between sender and receive, while caching is used to increase the speed of data processing by the CPU. In this article, we will discuss the important differences between buffering and caching. But before that, let's have a basic overview of buffering and caching so that it becomes easier to understand the differences between them. What is Buffering? The area in main ... Read More

Both Semaphore and Monitor are types of process synchronization tools in operating systems. Semaphores and monitors allow the different processes to utilize the shared resources in mutual exclusion, however they are different from each other. The basic difference between a semaphore and a monitor is that a semaphore is an integer variable, whereas a monitor is an abstract data type. Read this article to find out more about semaphores and monitors and how they are different from each other. What is Semaphore? A semaphore is a process synchronizing tool. It is basically an integer variable, denoted by "S". The ... Read More

In operating systems, both deadlock and starvation are unwanted situations that take place when the processes that need a shared resource block each other's progress indefinitely. Both are unwanted situations; however, a deadlock is quite different than a starvation. In this article, we will discuss all the important differences between deadlock and starvation. What is Deadlock? A deadlock is a condition in operating systems in which no process proceeds for execution and waits for resources that have been acquired by some other processes. Thus, in the case of a deadlock condition, the process simply gets blocked. Deadlock is also known ... Read More

In this post, we will understand the difference between RPC and RMI −RPC (Remote Procedure Call)It is a library.It is an OS dependent platform.It supports procedural programming.It is less efficient in comparison to RMI.It creates more overhead.The parameters passed to RPC is normal data.It is the older version of RMI.It is easy to program in RPC.It doesn’t provide any security.The cost of development is high.Versioning is a complicated process in RPC.Multiple codes will be needed to build a simple application in RPC.RMI (Remote Method Invocation)It is a platform based on Java.It supports object-oriented programming.It is more efficient in comparison to ... Read More

In this post, we will understand the difference between Time Sharing and Real-Time Operating System −Time Sharing Operating SystemIn this type of operating system, a quick response is required to be given when a request comes in.It has a switching method.Any kind of modifications can be done to the program.The resources of the computer are shared externally.It deals with multiple processes and applications simultaneously.The response to a user request is given within seconds of time.Real-Time Operating SystemIn this operating system, the computation tasks are required to be given more importance before its nominative point.It doesn’t have a switching method.No modification ... Read More