Talk:Dependability

From Wikipedia, the free encyclopedia

Socrates
Philosophy Portal
This article is within the scope of the WikiProject Philosophy, which collaborates on articles related to philosophy. To participate, you can edit this article or visit the project page for more details.
??? This article has not yet received a rating on the quality scale.
??? This article has not yet received an importance rating on the importance scale.

Contents

[edit] Most of the page disappearing

Some anonymous user just delete most of the page and rewrote it to be a dictionary definition of dependability. I've restored the page but perhaps we should thing about a disambiguation page.

Foobiker 10:30, 24 October 2007 (UTC)


I, for one, would like to see a disambiguation page. I came looking for dependability as it refers to humans and their interactions with one another. --Victoria 14:34, 21 January 2008 (PST)

[edit] Measures

At present times there are a few measures strictly defined by dependability papers and providing measurements is still a current challenge for dependability researchers.

Example of definition, from About.com: Measure is a noun, in the mathematical language of measure theory: a measure is a function from sets to the real line. Probability is a common kind of measure in economic models. Other measures are the counting measure, which is the number of elements in the set, the length measure, the area measure, and the volume measure. Length, area, and volume are defined along lines, planes, and spaces just as one would expect, and they have the natural meanings.

Given the definitions of the attributes in the article, only the first (availability) is correctly defined as a measure (probability). The others are defined as a "capability" (safety), "information" (confidentiality), "absence" (integrity), and "to undergo" (maintanality) and therefore could not be measured.

--Znorkiwsy 11:11, 16 October 2007 (UTC)

I agree that the attributes can be roughly split into two groupings, one qualitative the other quantitative (with a certain amount of fuzziness) but the attributes are qualities a dependable system possesses rather than direct measurements. Each attribute has measures that are qualitative and/or quantitative. It's probably my fault for not making this clearer in the text.

The definition given in Avizienis 2004 transaction paper lists the attributes and definitions as:

  • availability: readiness for correct service.
  • reliability: continuity of correct service.
  • safety: absence of catastrophic consequences on the user(s) and the environment.
  • integrity: absence of improper system alterations.
  • maintainability: ability to undergo modifications and repairs.

and possibly we should stick to these since it eliminates the confusion between attributes and measures.

It's been a while since I read the paper and I noticed that confidentiality isn't in the list but is mentioned afterwards in the context of security so I think it's worth making this distinction as well.

When addressing security, an additional attribute has great prominence, confidentiality, i.e., the absence of unauthorized disclosure of information. Security is a composite of the attributes of confidentiality, integrity, and availability, requiring the concurrent existence of 1) availability for authorized actions only, 2) confidentiality, and 3) integrity with “improper” meaning “unauthorized.”

Foobiker 09:20, 19 October 2007 (UTC)

[edit] Medical Field

I have a question. How can dependability relate to the medical field?

--

It depends on the specific context you're talking about I suppose.

For instance, conceptual if you are talking about the whole process of an operation then you would measure the system (i.e. the process of having an operation from start to finish say) using the dependability attributes. Availability would be fairly simple: 1) trained staff, 2) operating theater/bed space, 3) equipment available at the required time, etc. Reliability might be measured as the success rate of the operation. Safety you could assess using safety case criteria, i.e. are the staff correctly trained, is the equipment adequate, etc. Confidentiality would probably relate to non-discolure agreements not to pass on your medical records. Integrity is a bit of a tricky one, I suppose you might look at this in terms of staff making unauthorized modifications to procedures. Maintainability could be the ability to amend the operating procedure if required, i.e. to up the success rate of the operation due to new medical practices or piece of equipment.

What this article doesn't address at present are threats to dependability and means to increase dependability. (A job for this afternoon I think).

-- User:foobiker 14:24, 10 October 2007 (UTC)

[edit] Standard Definition of Dependability in Electrotechnical Engineering

This page does not consider the definition from IEC IEV 191-02-03, which is

dependability the collective term used to describe the availability performance and its influencing factors : reliability performance, maintainability performance and maintenance support performance

NOTE – Dependability is used only for general descriptions in non-quantitative terms.'

This world-wide harmonised definition does not cover safety and security. It should be at least mentionned. Why is it not?

Source: http://dom2.iec.ch/iev (search for dependability)

--88.70.114.156 19:33, 19 March 2007 (UTC)

In my mind, security is a means to raise the dependabililty level, not a requirement.--Znorkiwsy 11:11, 16 October 2007 (UTC)