Trusted software and viable software

the popularization and development of the Internet has provided people with a global information infrastructure, and also provides the possibility for the wide sharing and utilization of information resources. So in today's society, the Internet has become a part of people's lives, the popularization of computers has also promoted the development of the software industry. But in the course of class, we also understand the software crisis, software is not completely credible and feasible, which requires us to understand the software.

Freshman time, the teacher mentioned the most problem is the memory leak, the longer the software run the card, but after checking some information, found that the software problems may be many. The latest news, saying that the time of the Apple phone is set to 1970, then the phone will become a brick, the news has been proved correct. Imagine a company as big as Apple can have this problem, in daily life, we use the software is very likely to be a problem is still very high.

The difference between trusted software and viable software:

I. What is high-trust software?

The credible nature of software system is the key property that the system needs to satisfy; When software breaches these critical qualities can cause intolerable losses, it is said that these critical qualities are highly credible. Software is often trusted in the following ways:

Reliability (reliability) The ability of the software to operate without failure in the specified environment and within the specified time;

Reliable security (safety) software is capable of operating without causing danger or disaster;

The ability of security software system to provide confidentiality, completeness, availability and authenticity of data and information;

Survivability (survivability) software's ability to provide continuous service in the event of an attack or failure, and to restore all services within a specified time;

Fault-tolerant (faulttolerance) software guarantees the ability to provide services in the event of failure (hardware, environment anomalies);

The ability of the real-time (realtime) software to complete the response or submit output within a specified time period.

One or more of the above properties will be involved in a high-trust software system. These trusted properties, combined with the functionality of the software, complicate the acquisition and assurance of high-trust properties. The reason for this is that software, as a highly complex intellectual product of human being, is far from being fully understood by its scientific principles and engineering laws, and thus lacks the software technology to effectively produce software that satisfies high reliability.

two . What is a viable software?

　　The feasibility analysis is to decide whether to do or not. Demand Analysis is about deciding what to do and what not to do. We have written a feasibility study report is engaged in an economic activity (investment), the two sides from the economy, technology, production, supply and marketing until the various environmental, legal and other factors to carry out specific investigation, research, analysis, to determine the favorable and unfavorable factors, the feasibility of the project, the estimated success rate of the size, Economic and social effects, for decision-makers and competent authorities to approve the reporting documents.

What we say about software feasibility analysis, in fact, is about whether to develop this software to make value judgments, this analysis based on economic, technical, social environment and people, analyze the actual value of a software, determine whether we need to develop him.

To sum up, the feasible software refers to a valuable, worthy of our development of software, trusted software refers to high-quality, effective software.

Trusted software and viable software