The document discusses various attributes related to software quality and aging. It describes attributes from the SQuaRe model including functionality, reliability, efficiency, usability, and maintainability. It also lists additional attributes that may relate to software aging such as robustness, latency, accountability, accuracy, execution time, availability, accessibility, conformability, interoperability, learnability, understandability, operability, reliable messaging, transaction processing capability, recoverability, fault tolerance, analyzability, changeability, installability, replaceability, mean time between failure, downtime per year, performance, and stability.

1. ATTRIBUTES RELATED TO SOFTWARE AGING
Attributes of SQuaRe Model are:
 Functionality = suitability+accuracy+interoperability+security+functionality compliance
 Reliability = maturity+fault tolerance+ recoverability+reliability complaince
 Efficiency = time behaviour+resource utilization+efficiency complaince
 Usability = understandability+learnability+operability+attractiveness+usability
complaince
 Maintainability = Analyzability+changeability+stability+testability+maintainability
complaince
 Portability = adaptability+installability+co-existence+replaceability+portability
complaince
Other Attributes that may relate to Software Aging are:
 Robustness is the ability of a service to cope with errors during execution or the ability of an
algorithm to continue to operate despite abnormalities in input, calculations, etc.
 Latency is a measure of time delay experienced in a service.
 Accountability Measurement of the responsibility of a service towards some particular
things.
 Accuracy The quality of being near to the true value. The Quality of a service which works
correctly in utmost all situations.
 Execution Time The QoS attribute which measures the time taken by the service to finish it’s
execution.
 Availability: The implementation of the Qos of the overall service is done by providing
probability of availability guarantees for certain levels of QoS.
 Accessibility: this is nothing but making available of all the services to all the people without
any failure.
 Conformability: in web services that are used for particular purpose should ensure the
conformability for the users. That is, it is to the degree to which it initially meets its declared
quality specification throughout its useful life.
 Interoperability: The fundamental goal of interoperability in Web services is to blur the lines
between the various development environments used to implement services so that developers
using those services don't have to think about which programming language or operating
system the services are hosted on.

2.  Learnability Is the capability of a software product to enable the user to learn how to use it.
Learn ability may be considered as an aspect of usability, and is of major concern in the
design of complex software applications.
 Understandability The QoS attribute in which how easily a service logic can be easily
understood by any user.
 Operability is the ability to keep equipment, a system or a whole industrial installation in a
safe and reliable functioning condition, according to pre-defined operational requirements.
 Reliable Messaging: The goal of reliable messaging in Web services is to allow applications
to send and receive messages simply, reliably, and efficiently even in the face of application,
platform, or network failure.
 Transaction Processing Capability: transactions have an all-or-nothing property. The
actions taken by a transaction participant prior to commit are only tentative; typically they are
neither persistent nor made visible outside the transaction. When an application finishes
working on a transaction, it requests the coordinator to determine the outcome for the
transaction.
 Recoverability refers to the ability to restore your deployment to the point at which a failure
occurred. The ability to recover quickly from a system failure or disaster depends not only on
having current backups of your data, but also on having a predefined plan for recovering that
data on new hardware.
 Fault Tolerance The capability of a system to perform in accordance with design
specifications even when undesired changes in the internal structure or external environment
occur.
 Analyzability Understanding of analyzability is based upon a model of inquiry that assumes a
relative comparability among analysts as observing and influencing instruments.
 Changeability The extent of changeability is determined by the number of possible change
mechanisms available to the system as accepted by decision makers.
 Install Ability The ability of a software component or system to be installed on a defined
target platform allowing it to be run as required. Installation includes both a new installation
and an upgrade.
 Replace Ability Replace ability refers to the ability of substituting one service for another.
The effective management of service replace ability is important to make the applications
unaffected once the requested service cannot work.

3.  Mean Time between Failure is the predicted elapsed time between inherent failures of a
system during operation. MTBF can be calculated as the arithmetic mean time
between failures of a system. The MTBF is typically part of a model that assumes the failed
system is immediately repaired as a part of a renewal process.
 Downtime per year: The term downtime is used to refer to periods when a system is
unavailable. Downtime or outage duration refers to a period of time that a system fails to
provide or perform its primary function.
 Performance: Response time, Maximum throughput.
 Stability: (Availability, Accessibility, Success ability). Suitability for Standards: the
capability of which a Web service is communicable with the other Web service on a different
system or a platform.