Operating Systems
Scenario: Top Secret, Inc. (TSI) is a successful operating system company whose customers include Fortune 500 companies, governments throughout the world, and major U.S. contractors. TSI makes embedded operating systems for secure terminals that control ingress/egress control systems for Wall Street firms, camera systems for drone aircraft for government contractors, and alarm systems for top-secret government installations. TSI operating systems are world-renowned for their quick response to sensor input, highly reliable operation, limited memory utilization, small size on disk, and low power consumption.
| GPOS Feature | TSI OS Support for GPOS Feature |
| Multiprogramming | TSI OS does not support more than one program running at a time. TSI customers need one program resident, and that is the program that handles sensor input and (e.g., from cameras and motion sensors). A back-office operating system requires preemptive multitasking and advanced scheduling features. |
| Multiprocessing | TSI OS does not support more than one processor on a physical device. The operating system locks up when interrupts are generated by a second processor. Since most processors on the market are multicore, TSI has to purchase old, decommissioned hardware with single-core processors for its data center. |
| Multithreading | TSI OS lacks a system call interface beyond basic file open, close, read, and write. As such, it does not provide a CreateThread() or pthread_create() API call like Windows or Linux. Back-office applications that offer multithreaded operation hang at launch, so TSI has to use open-source software so that a team of TSI software developers can remove multi-threading functionality. |
| Virtual Memory | TSI OS uses a flat memory model without paging. As a result, TSI OS administrators in the back office frequently have to reboot the operating systems when they crash due to insufficient memory. |
| System Call Interface | As previously mentioned, TSI OS has only a basic system call interface. This causes severe software compatibility issues. To get around this limitation at TSI headquarters, developers have had to modify traps to kernel mode and develop custom system call responses. |
| Security | Given the fact that TSI OS operates based on sensor input, it does not have any security for log in, file system modifications, or network security. In customer installations, the system is typically located on a closed TCP/IP network, so operators can quickly get access to device statistics. As a result, anyone with network access at TSI headquarters can log into any TSI OS server in the back office. |
| Device Drivers | TSI software developers write custom device drivers for each customer. That does not work well for the TSI back office because the variety of devices is so large and sophisticated, TSI developers are unable to code for them. |
| Fault Tolerance | Given the device driver limitations of TSI software developers, they are unable to code device drivers for RAID cards. As a result, all company data resides on individual SATA and SCSI drives. |
The TSI Operating System (TSI OS) works exceptionally well on the devices owned by TSI customers, but it does not work well in the TSI back office. Like many startup companies, TSI had to cut costs when it launched a few years ago. To save money, the company decided not to use enterprise-class operating systems for its own workstations and servers. Instead, it chose to use a single-purpose TSI OS, reasoning that TSI OS was good enough for TSI customers, so it should be good enough for TSI. Unfortunately, TSI OS lacks many features of a modern operating system and does not take advantage of the architectural optimizations present in the latest hardware. Below is a matrix of general purpose operating system (GPOS) features and how they map to TSI OS:
Table 1: Mapping of the features found in a typical general purpose operating system compared to the TSI OS used at TSI headquarters for its back-office servers. The mapping shows that the choice of a single purpose OS for its back-office function has limitations that require an enterprise-class, general-purpose operating system.
Prompt
For this milestone, conduct an analysis of the situation in which TSI finds itself. Write a short paper that describes the business-related challenges faced by the organization. You are not describing solutions to those challenges just yet . Search for case studies or articles that discuss similar challenges faced by organizations with constraints related to the lack of features listed in Table 1 above. If you work in the information technology field, describe any similar operating-system-related challenges faced by your organization. If you are a consumer of IT services, describe how any of the features or lack thereof would play a role in your productivity at work or school.
Create a short paper that includes the following critical elements in this assignment:
1. A description of the business-related challenges faced by the organization
2. One example of a case study that discusses similar challenges faced by organizations with constraints related to the lack of features listed in Table 1, or
3. If you work in the information technology field, describe any similar operating-system-related challenges faced by your organization, or
4. A description of how any of the features listed in Table 1 or a lack thereof would play a role in your productivity at work or school.
