Process isolation in computer programming is the segregation of different software processes to prevent them from accessing memory space they do not have. The concept of process isolation helps to improve the security of the operating system by giving different levels of privilege to certain programs and restricting the memory that these programs can use. While there are many implementations of process isolation, it is often used in web browsers to separate multiple tabs and to protect the main browser itself if a process fails. It can be hardware-based or software-based, but both serve the same purpose of limiting access to system resources and keeping programs isolated in their own virtual address space.
Woman doing handstand with a computer
The basic workings of process isolation involves assigning a process or program a clearly defined virtual address space. This space contains the program and all related data. If the process requires more space, it will be requested from the operating system and allocated if available. In this way, the operating system can prevent two processes from accidentally or intentionally accessing each other’s memory.
Another purpose of process isolation is to allow programs to run while ensuring that they do not affect vital systems. It can prevent a program from trying to access key areas of the operating system and modify or otherwise change them. This allows a program to be terminated in the event of a problem without causing the larger operating system to also terminate.
There are different variations of insulation. One is to assign privileges to process so that they can access specific resources on one system while still protecting others. This is usually done to allow a program to use an Internet socket or printer, while restricting access to a disk drive or file system.
There are also situations where certain steps can be taken to allow different processes to communicate securely with each other but continue to keep them independent of each other. Through mechanisms such as inter-process communication (IPC) and shared memory, processes can exchange information but still be restricted to their own memory space. This functionality is important when a process requires information from different management processes belonging to the operating system.
Process isolation is an important software and hardware feature that helps make many technologies possible. Virtual machine servers operate with an advanced form of process isolation based on hardware and software management. Being able to run applets or other scripts from websites safely depends on a process isolating important system resources. Mobile devices and embedded systems use process isolation to allow core hardware to remain secure despite any faulty or malicious software running.