Updated on November 18, 2018 by admin
ISEB Software Testing Foundation training courses introduce students to the fundamentals of software testing, including the reasons for carrying out tests, basic test processes and the general principles that underpin testing good practice. Knowing these principles, and understanding how they affect the software tester, is crucial to passing the ISEB Software Testing Foundation exam.
1. Testing shows the presence of bugs
That is, testing can show that problems exist, but not that problems do not exist.
This principle lies at the core of ISEB Software Testing guidance. An astute test analyst understands that even if a test does not reveal any faults, the subject of the test is not necessarily error-free.
The key objective of carrying out a test is to identify defects. Working under the assumption that every product will contain defects of some kind, a test that reveals errors is generally better than one that does not. All tests should therefore be designed to reveal as many errors as possible.
2. Exhaustive testing is impossible
Exhaustive testing feeds all possible data combinations into the software, in order to ensure that no untested situation can arise once the software has been released. Except on extremely simple applications, the number of possible data combinations is forbiddingly high; it is more effective and efficient for testers to focus on risks and priorities, so that the tests are targeted to the testing needs.
3. Early testing
A product (including documents, such as the product specification) can be tested as soon as it has been created. The ISEB software testing guidance recommends testing a product as soon as possible, in order fix errors as quickly as possible. Studies have shown that errors identified late in the development process generally cost more to resolve.
For example: an error in a product specification may be fairly straightforward to fix. However, if that error is transferred to the software coding, then fixing the mistake could become costly and time-consuming.
4. Defect clustering
Studies suggest that problems in an item of software tend to cluster around a limited set of modules or areas. Once these areas have been identified, efficient test managers are able to focus testing on the sensitive areas, while still searching for errors in the remaining software modules.
5. The ‘pesticide’ paradox
Like over-used pesticide, a set of tests that is used repeatedly on the same software product will decrease in efficacy. Using a variety of tests and techniques will expose a range of defects across different areas of the product.
6. Testing is context dependent
The same tests should not be applied across the board. Different software products have varying requirements, functions and purposes. A test designed to be performed on a website, for example, may be less effective when applied to an intranet application. A test designed for a credit card payment form may be unnecessarily rigorous if performed on a discussion forum.
In general, the higher the probability and impact of damage caused by failed software, the greater the investment in …
Updated on November 18, 2018 by admin
Ever wondered what are these tiny chips? Confused by the names?
We are here to help you.
This article is about the various memory components available in the market for mobile phones.
MS Memory Stick is a removable flash memory card format, launched by Sony in October 1998, and is also used in general to describe the whole family of Memory Sticks. This family includes the Memory Stick Pro, a revision that allows greater maximum storage capacity and faster file transfers speeds, and Memory Stick Duo, a small-form-factor version of the Memory Stick.
50.0 x 21.5 x 2.8 mm
Memory Stick Duo
31.0 × 20.0 × 1.6 mm
The Memory Stick Duo, which is slightly smaller than the competitive Secure Digital format, was developed in response to Sony's need for a smaller flash memory card for pocket-sized digital cameras and cell phones, as well as Sony's PSP. Memory Stick Duos are available in all the same variants as their larger cousins (normal ones limited to 128 MB, larger Pro Sticks, with and without High Speed mode), and a simple adapter (often sold together with the Memory Stick Duo) allows a Duo to be used in any device that can accept their larger cousins.
Memory Stick Micro M2
15.0 x 12.5 x 1.2 mm
Sony announced a new Memory Stick format on 30 September 2005. The new Memory Stick M2 ("micro") measures 15 x 12.5 x 1.2 mm and could theoretically have 32GB in the future. Maximum transfer speed is 160MB / s. It will come with an adapter, much like the Duo Sticks, to ensure compatibility with current Pro devices.
Multi Media Card
32 x 24 x 1.5 mm
The MMC card or MultiMediaCard was introduced in 1997 by SanDisk Corporation and Siemens AG. At that point the MMC card was the smallest memory card, about the size of a postage stamp, in the market based on flash memory technology. The MMC card is very similar to the Secure Digital Memory Card, actually the SD Memory Card is based on the MMC card. They have almost the same form factor the only differences are that the SD Memory Cards are slightly thicker and they have a write protection switch.
Since the MMC card had slow transfer speed, 2.5 MB / sec, in comparison to other memory cards, mostly compared to SD Memory Card, a new high performance version of the MMC card was introduced in 2005 by the name MMCplus. The MMCplus has today the highest, up to 52 MB / sec, theoretical data transfer speed in the whole memory card industry.
The MultiMediaCard Association announced that by the end of 2005 the secureMMC application will only be available for the MMCplus and MMCmobile memory cards. The SecureMMC is a copyright protection application that features DRM, Digital Rights Management, and VPN, Virtual Private Network, capabilities.
Reduced Size Multi Media Card
16 x 24 x 1.5 mm
RS-MMC, Reduced Size MultiMediaCard, was introduced …