A Tale of Clouds: Paradigm Comparisons and Some Thoughts on Research Issues

Lijun Mei, W.K. Chan, T.H. Tse

http://ieeexplore.ieee.org.proxy.lib.sfu.ca/stamp/stamp.jsp?tp=&arnumber=4780718&isnumber=4780615

Preliminaries

Cloud Computing

• Horizontal Cloud Scalability: connect and integrate multiple clouds to work together as one logical cloud
• Vertical Cloud Scalability: improve the capacity of a cloud by enhancing the individual nodes in the cloud

Basically the above concepts talk about scalability in depth and scalability in breadth

Service Computing

• to create a service composition, engineers may use specifications such as WSBPEL
• to carry out workflows, webservices or other types of services might be used

Pervasive Computing

• embedded in constantly changing computing environments
• a well developed environment will enable the pervasive software to work eveywhere without extra effort
• Environmental features are used to understand and react to the users. These environmental variables are referred to as context and are collected using different sensors and information in the environment

Comparing Cloud with Pervasive and Service Computing

• Service Computing is good in providing functionality and providing flexible services
• Pervasive Computing enables users to use software everywhere and provides slef adaptivity with respect to the environmental contexts

Cloud computing needs both functionality modeling and context sensitivity.

In terms of IO Cloud Computing is closer to Service Computing
In terms of storage, Cloud Computing seems to be closer to Pervasive Computing

Comparison of IO for cloud, service, and pervasive computing


Comparison of storage for cloud, service, and pervasive computing
Comparison of calculation features for cloud, service, and pervasive computing

How do computing entities plug into the system?

• service computing: registration and discovery of srvices
• pervasive computing: mobile computing entities join and leave the environment
• cloud computing: Applications can be entity aware to plugin heterogeneous computing entities. New computing entities can be added or should be added to the system dynamically and on the fly.

How do computing clouds store and access large-scale data?

• Pervasive computing: mobile entities store their data in the environment
• Service computing: usually the amount of data stored is negligible and services are more often stateless services which do the calculation but do not deal with storing information
• Cloud Computing: there is finite amount of space for storage on the cloud too, so cloud systems may need to share data or may need to provide some sort of inter-cloud communication in order to scale better and transfer some of the data to other clouds

How does a computing cloud become adaptive to both internal and external changes?

• Service computing: environmental changes, evolving quality of services,
  
• Pervasive computing: quality of mobile entities involved
• Cloud computing:
  
• How does the environment change for a cloud?