4.2.4 a summary

Chapter 4Examining Cloud ComputingFrom the Perspective of GridAnd Computer-Supported Cooperative Work

Jinlei Jiang and Guangwen Yang

Table 4.1 summarizes the differences between grid and cloud computing. The key points are highlighted below.Grid computing adopts a resource-centric design and tries to meet various needs by a unified resource pool. As a result, many unnecessary details of the infrastructure are brought to both end-users and developers, making it difficult to use and hard to program. In addition, it also raises a heavy burden of system administration due to many administrative domains being involved.

4.2.4 A Summary

4.2.4 A Summary

Cloud computing, on the contrary, adopts a user- and task-centric design and it meets diverse needs by different kinds of services, for example, infrastructure services, platform services, and software services. In cloud computing, the complexity is shielded from users. As a result, it is easy to use and program. In addition, managing a cloud is also easy since for most of the time there is only one administrative domain involved in it.

4.2.4 A Summary

4.3 Examining Cloud Computing from the CSCW Perspective

• In the previous section, we examined the differences between grid and cloud computing. In this section, we present some findings in CSCW (Computer-Supported Cooperative Work) research and utilize them to analyze the cloud.

CSCW is a research field dealing with the issue of how to use computers, or more broadly information and communication technology (ICT), to facilitate a group of people to fulfill a common task [6]. Over 20 years of development since the term was first coined in 1984, people have gained much knowledge about this field. Cloud computing holds the promise to deliver computing as a utility, so it is a socio-technical system (社會的技術系統 ). It is in this sense that we think that the following findings of CSCW (Computer-Supported Cooperative Work) can also be used to answer the questions raised in Section 1 – why cloud computing is so attractive and how to make the vision of cloud computing really come true?

4.3.1 CSCW Findings

Finding 1: To derive the greatest benefit from CSCW, the supporting technology must infiltrate (滲透 ) as widely as possible throughout the populace (全體居民 )[16]. In this way, cooperative system designers can relieve themselves from hard work on such issues as heterogeneous resource management and interoperability and focus their efforts on more essential issues such as understanding and accounting for the characteristics of cooperative work and then devising (設計 ) proper mechanisms to support them.

4.3.1 CSCW Findings (Computer-Supported Cooperative Work)


• Finding 2: Besides technical factors such as usability and functionality, the deployment of CSCW (Computer-Supported Cooperative Work) is affected by social factors such as various administrative and policy decisions [16]. Sometimes, the social factors function dominantly in making the decision on whether to adopt a certain technology or not.

Finding 3: A successful collaborative (合作的 ) system must provide enough respect for the social habits of end-users [9]. Human is the most active and dynamic element in a collaborative environment, and providing respect for his/her habits means users can get better experiences during collaboration. This in turn implies that the collaborative system will be adopted by more and more users, and therefore, the critical mass (眾多 )problem [14] will easily be met.


Finding 4: Incentives (動機 ) are critical [1]. CSCW suffers from Grudin’s inequality [9], which says that those who do additional work (capture and record the articulation (接合 ) work associated with collaboration) to make collaboration succeed may not be the ones who benefit most from the results, and thus it is necessary to provide some incentives or reward to those persons. In this way, more people will join the collaboration process and the contribution of people will also increase.

4.3.1 CSCW Findings (Computer-Supported Cooperative

Work)

The attractiveness of cloud computing can be accounted for using Finding 1, Finding 3, and Finding 4 as follows.First, cloud computing, in general, presents no new technology. Virtualization technology, which is at the core of cloud computing, was first developed in the 1960s. Other technologies such as web services and Rich Internet Applications (RIA) also have a history of no less than 5 years. Today, all these technologies are well supported and popular.

4.3.2 The Anatomy of Cloud Computing

For example, Intel and AMD have released several processors with support for virtualization technology and there are many virtual machine monitors (VMMs) available on the market (e.g., ESXi and vSphere from VMware, Hyper-V from Microsoft, XEN and KM from the open-source community). In addition, web services and RIA (Rich Internet Applications) have become a must for the development of web applications. Thus, adopting these technologies sets up a good basis for the prosperity (繁榮 ) of this market because it makes entrance low. As a contrast, there was no prevalent (流行的 ) integration technology at the beginning of grid computing and designers have to develop their own ways to integrate various resources.


Though the convergence of grid computing and SOA (Service-oriented architecture) provides new opportunities for resource integration, much work is still needed to reconcile various ways of information representation. Put simply, the entrance for grid computing is high. As a result, even after 10 years of development, grid computing today is still in its infancy in many aspects [12].Next, cloud computing provides enough respect for the social habits of users because using a machine in the cloud is no different to using a local machine. As mentioned above, users of cloud computing can always work with their familiar tools and settings. In other words, users of cloud computing adapt the running environment to their applications rather than adapt the applications to the environment. Therefore, they do not need to change habits developed over years, which have a solid base.


On the contrary, as we discussed in Section 2, users of grid computing, whether end-users or application developers, have limited, if any, control over the running environment, and have to bear many constraints being put on them. For developers, to take the full advantage of grid computing, they have to learn much for developing new applications or adapting the existing ones to the grid, which is a heavy burden to them. In addition, system administrators also face many new challenges in coordinating resource sharing and in guaranteeing the reliability, availability, and security of the running environment due to the involvement of multiple autonomous (自主的 ) domains.


The last but the most important point, users of cloud computing need not do much, if any, additional work to use the services provided by the cloud. All the work they do is necessary and the same as what they do every day without cloud computing. For example, reserving a VM in clouds is an analog of buying a physical machine, but with much greater convenience. Installing software in a VM is no different to that in a physical machine. What’s more, users can benefit from the advanced features of cloud computing such as unlimited resource being available on demand, no upfront (預付的 ) commitment (承諾 ) and pay-as-you-go usage of resources [2], and the great potentials for group collaboration as well as the universal access to information and services [15].


These features are especially attractive to small- and medium-sized businesses (SMBs) or start-ups that do not have enough resources for buying and maintaining servers and developing applications from scratch (起跑線 ), for they imply a lot of savings of running costs. In contrast, things are quite different with grid computing. To use grid computing, much more should be paid on application development, system management, and so on. Particularly, since resource providers in grid computing receive no reward for sharing their resources, they are reluctant (勉強的 ) to help to solve various problems encountered.


In summary, compared with grid computing, cloud computing provides more benefits and rewards without changing the working way that people are familiar with. Therefore, it is not strange at all that cloud computing is attractive. Indeed, cloud computing has accumulated a huge (potential) base of both service providers and consumers, and many market-research firms (e.g., IDC, Forrester, and Merrill Lynch) believe that cloud computing has enormous growth potential.In spite of the facts above, cloud computing is still in its infancy and only has a limited adoption to now [11]. To make the vision of cloud computing really come true, we examine the obstacles (障礙物 ) to (rapid) growth of cloud computing.


As with any other new paradigm (範例 ), there are fears and concerns about cloud computing related to technology, social factors, or both. For example, Armbrust M et al. [2] listed the top ten obstacles as availability of service, data lock-in, data confidentiality (機密 ) and auditability (可聽見的 ), data transfer bottlenecks, performance unpredictability, scalable storage, bugs in large-scale distributed systems, scaling quickly, reputation (名聲 ) fate (命運 ) sharing and software licensing; Leavitt N [11] identified the challenges facing cloud computing as control, performance, latency, security and privacy, related bandwidth costs, vendor lock-in (關在裡面 ) and standards, transparency, reliability, and others.


In our opinion, issues such as performance, latency, scalability, and data transfer bottlenecks are related to technology and have been suffered for a long time before the emergence of cloud computing. Though they have some impact on the adoption of cloud computing, the impact is limited. It is the following issues that hinder the wide adoption of cloud computing.


According to a survey by IDC, security and privacy is the main concern of chief information officers and IT executives [11]. To us, such a concern arises from the violation or change of users ＇ social habits-data and applications in cloud computing are usually stored or running on an external infrastructure outside a company’s firewall, and users have to rely on service providers NOT themselves, to protect their data and applications. Obviously, this may be quite different from what users are used to when using local machines. Since change of habit is a slow process, it is a natural result that only cloud computing has a very limited adoption just now according to Finding 2 and Finding 3. However security and privacy might be only a perceived risk as asserted by Armbrust M et al. [2]:

4.3.2.1 Security and Privacy

We believe that there are no fundamental obstacles to making a cloud-computing environment as secure as the vast majority of in-house IT environments, and that many of the obstacles can be overcome immediately with well-understood technologies such as encrypted storage, Virtual Local Area Networks, and network middleboxes (e.g., firewalls, packet filters).

4.3.2.1 Security and Privacy

This concern arises from the fact that there are currently no standards for IaaS, PaaS and SaaS interfaces, and as a result, much work is needed for customers to port their data or programs from one cloud to another. While we admit that such concerns really matter it will become increasingly important as more and more cloud providers emerge, we also argue that its impact may not be as great as people think. On the one hand, people undergo such constraints in the real world. For example, designers have to make a choice between J2EE and .NET platform when developing new applications. When new hardware is bought, people have to install system and application software again to deliver their services.

4.3.2.2 Data and/or Vendor Lock-In

If we treat migrating an application from one infrastructure to another as the process of buying new hardware, the inconvenience caused by incompatible virtual image formats – a major problem with IaaS – would no more be a problem. On the other hand, people have recognized this problem and as a result, many standardization activities are in progress. Some of them are listed below. For more information, please refer to http://cloud-standards.orgCloud security Alliance² was set up recently “to promote the use of best practices for providing security assurance within Cloud Computing, and provide education on the uses of Cloud Computing to help secure all other forms of computing. ”


http://cloud-standards.org/

http://cloud-standards.org/

The Open Grid Forum (OGF) established the Open Cloud Computing Interface Working Group (OCCI-WG)³ in March 2009 to develop a clean, open API for infrastructure clouds. The Storage Networking Industry Association (SNIA) has created a technical workgroup to develop the new Cloud Data Management Interface (CDMI).⁴ The Open Cloud Consortium (OCC),⁵ another newly established organization, aims to “support the development of standards for cloud computing and frameworks for interoperating between clouds.” Finally, the Distributed Management Task Force (DMTF) has released the Open Virtualization Format (OVF) Specification [5] that “ describes an open, secure, portable, efficient, and extensible format for the packaging and distribution of software to be run in virtual machines.” Therefore, it is reasonable to believe that interoperation between clouds will get easier, making the concern about data/vendor lock-in less important.


This concern ranked first in the list given by Armbrust M et al. [2]. It is a radical requirement of business continuity – users will not adopt a system that is unreliable and often unavailable to run their business. The reason why such a concern becomes so important lies in the change of operating mode – services are running outside a company’s firewall and the quality of services relies not only on software vendors who develop services but also on providers who host services. No doubt, the well-known outages of Amazon S3, Google App Engine, and Salesforce.com make the worry even much severe. However, as pointed out by Armbrust M et al. [2], the IT infrastructures of Amazon, Google, and Salesforce are better than their peers.

4.3.2.3 Service Availability/Reliability

In summary, as a new paradigm, cloud computing does bring changes to business operation; that is, the operation is done remotely, out of the users reach and full control. Since this differs from what users are used to, it is natural to see that much concern is raised according to the Findings 2 and 3. To address this, time matters. We need time to tackle technical challenges; we need time to cultivate (培養 ) application developers; we need time to build trust between customers and service providers; we need time to develop use cases to demonstrate the benefits of cloud computing. Once people get to know the reward of cloud computing over its risks, the wide adoption of cloud computing will come true as implied by Finding 4.

4.3.2.3 Service Availability/Reliability

In this chapter, we first examined the differences between cloud and grid computing from their development and the viewpoint of system and users, respectively. Then, we analyzed the reasons why cloud computing is so attractive and some related concerns using the findings in CSCW research. Since cloud computing adopts a user- and task-centric design philosophy and shows enough respect for the social habits of users in using computers, its popularity is a natural result.

4.4 Conclusions

At the same time, like any other new thing, cloud computing faces some challenges that slow its wide adoption. As time goes on and more and more experience is gained, cloud computing will eventually become an effective and efficient way to deliver computing as a utility. During this course, we researchers should address how to overcome the obstacles and demonstrate the real benefits and/or advantages of cloud computing.

4.4 Conclusions

4.2.4 a summary

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