You can refer to a number of works that have already been done to evaluate the QoS of a variety of cloud services. The main things are:

1. A proper identification of the cloud service type (because every application has its own unique requirements)

2. A proper selection of the QoS parameters that you hypothesize may affect the service under consideration.

A lot of good work has been done in this as well as other related fields, and therefore I guess you wont have to search a lot.

Happy Research :)

Dear Jess Moutalameso,

to estimate the Quality of Cloud Computing Services, the Cloud Service Measurement Index Consortium (CSMIC) has specified several Criteria for QoS Assessment of Cloud Computing Services. These Quality Criteria (Agility, Performance, Security & Privacy, ...) can also be taken as a kind of Metrics.

For (Cloud Computing) Service Measurement Index Framework (Version 2.1) see the address:

http://csmic.org/downloads/SMI_Overview_TwoPointOne.pdf

In addition, I would recommend the following, very good source of literature:

Saurabh Kumar Garg, Steve Versteeg, Rajkumar Buyyaa: A framework for ranking of cloud computing services

http://cloudbus.cis.unimelb.edu.au/papers/RankingClouds-FGCS.pdf

Best regards and much success

Anatol Badach

Hello Jess

The colleagues above have provided valuable hints. However they seem to focus on "internal" aspects of Cloud QoS.

You may increase the interest of your work for outside readers by adding an other aspect: impact of end to end QoS of an Enterprise from using Cloud Computing services.

Can I highlight, as an illustration among many, the case of the transportation industry? British Airways has experienced several major outages linked to having a Cloud Service to power its airline service operation. We have seen recently a one day black out where all their flights had to be cancelled, due to a Cloud issue. This gives further importance to the work you're doing. The British Airways problem seems to have been traced to a "simple" power outage on a blade memory (a type of storage drive) used in Cloud. The problem cascaded into a passenger nightmare, with aircrafts nailed to the ground (faulty service design? Lack of fault tolerance in operation?). Another one has been a half-day disruption of the flight display system at Heathrow airport, with all screen information on arrivals and departures had to be replaced by handwritten paperboards (markers and paper, can you believe it?) The largest airport in Europe had probably, like the Titanic ship, become overconfident in its Cloud based information system.

I have also observed faulty public information systems at major train stations in the UK: very large displays visible to hundreeds of people simultaneously were not displaying train times but Microsoft Windows error messages. The best known fast train service between Paddington station in central London and Heathrow Airport, "the Heathrow Express" sometimes has onboard public display outage, with error messages in Spanish (just meaning that the software has been subcontracted to a supplier in a Spanish speaking country, and not sufficiently reliably integrated).

Consider QoS (service depending of Cloud service) and mitigation or error recovery procedure in case of fault.

thank you so much everyone for your directions

it helps me to find a problem based with cloud services.