Cloud Service Mediation through Brokerage Service
Claudio Giovanoli
Institute of Information Systems, University of Applied Arts and Sciences Northwestern Switzerland, Olten, Switzerland
1 RESEARCH PROBLEM
The advent of cloud computing has introduced an
entirely new way of thinking about IT services and
their role within an organization. It is in many ways
consistent with the general shift in focus to the
outsourcing trend that has become common practice
in modern businesses. Outsourcing lets businesses
concentrate on their core competencies while
simultaneously taking advantage of the core
competencies of their service providers – whether in
accounting services, manufacturing and any number
of other business activities. Cloud computing is the
manifestation of this trend applied to the day to day
operations traditionally delivered by internal IT
departments. As cloud computing services mature, an
increasing number of businesses will choose to move
their IT applications to the cloud (Cambridge
Technology 2011) to take advantage of the benefits it
can deliver.
Common IT services like file storage, e-mail,
databases, web sites, and many others can be pushed
into the cloud – leaving businesses to shift greater
focus and effort to delivering their own products and
services to their customers. The National Institute of
Standards and Technology (Mell and Grance 2011)
identifies the following characteristics associated
with cloud services:
1. On-demand self-service – a consumer is able to
provision computing power, network storage and
other capabilities automatically and as needed
without interaction of a human.
2. Broad Network Access – all services are provided
over the network and are accessible using
standard thin and thick clients such as traditional
workstations, tablet PC’s and even smart phones.
3. Resource Pooling – the service provider’s
computing resources are pooled together in what
is called a multi-tenant model. These resources are
dynamically assigned and reassigned to different
tenants as needed (according to demand).
Examples of such resources include memory,
bandwidth, processing power and storage.
4. Rapid Elasticity – the ability to scale up or down
on demand and often automatically gives the
customer valuable flexibility to meet the needs of
the business.
5. Measure Service – the customer pays only for
what is used. The consumed re-sources are
monitored, controlled and reported upon. This
provides transparency to both the customer and
the service provider. The IT services are
essentially billed to the customer like a traditional
utility company.
Having understood the benefits these characteristics
could potentially deliver, companies are taking notice
and looking to capitalize on this new paradigm of IT
services. To find the right service with the right
quantity and quality so called cloud service brokers
are playing an intermediary role between the
providers and customers.
Companies and organizations planning to use
cloud services are facing today a huge number of
different possible cloud solutions. Because of the
sheer number of possibilities it is hard to orient
oneself and find the optimal solution and offering.
Cloud Brokering companies are offering the
provision of an optimal service to its customers. This
time consuming process stands in opposite to the
cloud paradigms of fast provision and on-demand
self-service of a service. Thus, an automated
brokerage approach could leverage advantages of
cloud computing and increase companies’ agility.
If a company would like to examine if it is able to
use cloud services, different aspects like process
requirements, data security etc., have to be
considered. According to (Xin and Datta 2010) no
best practices or other manageable methods are yet
available to support customers in investigating these
aspects.
The analysis of own requirements can be a very
time intensive task. But also the selection of an
appropriate provider and service are a complex
challenge, especially for small and medium
enterprises with no or low IT expertise.
This research projects picks up these issues with
the goal to simplify the high complexity. Thus the
needed effort for an integrated Cloud Service
Mediation (from requirements analysis, service
Giovanoli, C.
Cloud Service Mediation through Brokerage Service.
In Doctoral Consortium (DCCLOSER 2016), pages 9-13
9
classification and the appropriate mapping) should be
diminished.
Therefore the thesis statement is defined as
follow: There exists a method to mediate cloud
services based on user requirements and cloud service
quality properties. This method is easy to use for
customers and can deliver automatic decision
support.
2 OUTLINE OF OBJECTIVES
This research project foresees three main objectives,
which can be identified as a part of such an integrated
Mediation Broker approach. The main goal is to
support SME’s using cloud services and to simplify
the due diligence process. From a scientific point of
view, this means that three main aspects have to be
investigated:
How can customers easily define, collect and
describe their business and functional
requirements. Thus, a requirements evaluation
method has to be developed. Main properties of
such a method should be:
a. Simplicity to understand for business;
defining a language which makes Cloud
necessities understandable for people with a
low technical affinity
b. Easy to use; in this case the project is intended
to find an appropriate form of self-services for
the needs assessment and service selection. A
high degree of self-explanation of the
operation of the system is aimed. The usage of
the self-service should be as simple as possible
to gain access to the required information.
c. Machine readable; whereas results are derived
from the customer analysis, they will be used
for input for the mapping component, this
must also be described and understandable for
the mapping system
Cloud services must be identified, described and
have to be classified qualitative and quantitative
so that a statement of compliance with the claimed
customer requirements can be made. Areas for
classification criteria could be for example:
a. Contractual aspects
b. Operational processes
c. Properties of Service Level Agreements
d. Training and Support
e. Interfaces and Interoperability
How can data from I and II be automatically
mapped to derive an optimal match of cloud
service quality and customer requirements.
The following figure should give a short impression
on the entire system, beginning at the requirements
assessment, to the service classification and finally
the mapping of the services to the requirements.
Figure 1: Cloud Mediation.
The three main objectives can be summarized as
follow:
1. Defining and developing a method to collect
customer’s business and functional requirements
with regards to a cloud service. The method has to
be easy to understand and usable for users without
IT background.
2. Defining a classification and weighting scheme
for cloud services with regards to service quality.
3. Evaluating an appropriate technology for
mapping data retrieving from objective 1 and 2.
Based on the chosen technology a proper system
has to be developed to mediate cloud services
easily to the customer.
3 STATE OF THE ART
The functionality and the role of a so-called Cloud
Brokers are discussed at international level for some
time. According to the National Institute for
Standards and Technology (NIST), there exist the
following three forms of brokering services in the
cloud environment (NIST 2013):
Service-Intermediation: A cloud broker adds a
given service by improving the ability of some
specific services for cloud consumers. Such
added-values can be a management access,
personnel management, performance reporting,
enhanced security, etc be the actual service.
Service Aggregation: A cloud broker combines
and integrates multiple services into one or more
new services. The broker provides data
DCCLOSER 2016 - Doctoral Consortium on Cloud Computing and Services Science
10
integration and ensures the secure data movement
between the cloud consumer and multiple cloud
providers.
Arbitrage-Service: Service arbitrage means that a
broker can choose from different services from
various providers. A cloud broker, for example,
can choose a suitable selection (Cloud Service
Selection) out of various offerings based on
different criteria.
Whereas on the field of intermediation and
aggregation (e.g. on the topic of interoperability)
already a lot of scientific effort takes place
(Sundareswaran et al., 2012) and various solutions are
available (Sun et al., 2013; Gartner, 2013), there is
only limited knowledge and on a high level of
abstraction in the field of arbitration (Kalepu et al.,
2003; Mondal et al., 2010; Buyya et al., 2012). At this
level first scientific efforts were taken of Buyya et al.
(Buyya et al, 2012; Garg et al., 2011). Buyya looks
such a broker as a central role for a market-oriented
approach of cloud services (Garg et al., 2011).
Silas et al., (Silas et al., 2012) propose a service
middleware for efficient service selection. By using
the ELECTRE methodology of the selection process
is approached as a multi on criteria decision problem.
Many criteria, such as response time, service costs,
responsiveness, trust, scalability, performance,
flexibility thereby influence the selection process.
Deng et al. (2011) used for service selection also a
multi-criteria decision-making process, which is
based on the Fuzzy-AHP (Saaty, 1986) and TOPSIS
method.
Furthermore, (Deng-Neng et al., 2011) is using
trust as the sole criterion for the selection of service
providers. Garg et al., (2012) focus their work on the
indexing and classification of the provider, which is
required for a service switching. A so called cloud
service index with parameters such as service type,
price unit, security provider is used. The whole
concept is based on the provision of data by the
respective provider and thus does not provide
independence from the service provider.
The existing activities focus either on the side of
the classification of services or the decision support
methods for the customer. Grag et al., (2012) and
Hussain (2011) also complain about that today's
cloud based service evaluation and selection methods
and in particular functional requirements. For a
successful service selection and service mapping but
also the business needs, as well as non-functional
requirements such as potential regulators,
Performance, Support etc. must be considered and the
service characteristics are com-pared.
The field of Business / IT Alignment (BITA)
seems to be suitable. BITA aims to align, adapt and
integrate business strategy, IT strategy, business
infrastructure and IT infrastructure with each other
(Henderson et al., 1993; Papp, 2001). In this field
there exist various approaches (plugIT, 2012, Wolf et
al., 2011) on how BITA has to be applied and used.
However, these methods are not suitable for the
selection and placement of cloud services, because of
the time consuming processes. Such as experiences
from the plugIT project (2012) have shown in other
areas, the efforts of such frameworks are not practical
for the users.
With regards to the mapping mechanism, the
complexity of such structures have to imply that
corresponding comparison algorithms have to have a
high tolerance for structural deviations without
harming the semantic content of the compared
entities. One way to take this into account are
approximate comparison methods based on
similarity-based reasoning. Among them there exists
a wide range of techniques including Case Based
Reasoning techniques such as example-based
reasoning, instance-based reasoning, memory-based
reasoning, or analogical reasoning (Wolf et al., 2011;
Aamodt, 1994).
4 METHODOLOGY
At this stage of the research project, pragmatism is the
right stance, because it offers the greatest flexibility
within the research project. The disruptive nature of
cloud computing and the resulting complexity within
the vendor landscape might still hold sur-prises along
the way. As research progresses and knowledge for
the development of a mediation broker will mature, it
is crucial in this research to adapt quickly.
As discussed in the previous chapters extensively,
cloud computing evolves at a great pace and the focus
in this market changes constantly. As a consequence
it is getting more difficult to keep the pace and stay
on top of things in the shifting cloud environment.
This rapid evolvement in its early stage makes it even
harder to develop a robust theory to test and validate
(i.e. deductive reasoning), which could withstand the
disruptive nature of cloud computing. However,
literature is available in this area, which would favour
a deductive approach thoroughly. As a pragmatist and
while looking be-yond the horizon, it might be
meaningful to combine both approaches. In the first
stage the inductive approach helps to break down the
complexity and explore the transition in the cloud
vendor market. Then, in a second stage when the
complexity decreased and less debate is excited,
Cloud Service Mediation through Brokerage Service
11
deductive reasoning can complement research with
more pro-found theories and results. Finally, the
foreseen approach is to collect data first and then
develop a theory out of it while keeping in mind that
deductive reasoning still will be applied in a later
stage.
Strategy: Design Research, also referred to as
Design Science research (Vaishnavi 2007) is
particularly suited to Information Science
research and is grounded in the types of research
questions that are often asked within this field
(Vaishnavi, 2007). This research will follow the
process steps as described by (Vaishnavi, 2007),
which requires looking at the problem of service
brokerage in a cloud environment and extracting
possible solutions from the existing knowledge.
Time Horizon: the intended research will follow a
cross-sectional approach as it is per-formed at a
particular point in time.
Data Collection: with regard to the Design
Science Research phases (Vaishnavi, 2007) the
following data collection methods and partners
are intended:
o Awareness of the Problem: in this phase
literature review will be conducted and
interviews with governmental partners and
SME Associations will be held.
o Suggestion: in the suggestions phase
interviews and workshops with different
responsible roles within SMEs, Expert
Interviews with Consultant e.g. Auditors and
Scientific Experts will be held. First artefacts
will be developed in cooperation with
technical experts
o Development: developing of prototypes with
technical experts from software developing
companies and scientific experts.
o Evaluation and conclusion: for the evaluation
different test cases will be prepared and
afterwards tested with potential customers
from (SMEs and governmental institutions).
Results will be discussed with technical and
scientific experts.
5 EXPECTED OUTCOME
This PhD project is closely coupled with the CLIMB
research project funded by Swiss Commission for
Technology and Innovation. The author is also
CLIMB’s project lead. Goal of this project is to
develop and establish kind of a Service mediation
broker based on the Star Audit Certification. Thus,
the outcome of this PhD project is two folded. On the
one hand there will be a practical outcome. It is
expected to develop a software, which (i) supports
customer to identify their needs regarding cloud
services, which (ii) offers to providers the opportunity
to classify their services and to compare it with other
providers and (iii) which maps these described
services with the claimed client requirements and
gives a valuable recommendation of appropriate
services.
On the other hand it is expected that the project
will bring some scientific contributions like:
A method to collect customer’s business and
functional requirements with regards to a cloud
service. The method has to be easy to understand
and usable for users without IT background.
An evaluation method for benchmarking data
mapping methods based on a given mapping
challenge.
A classification and weighting scheme for cloud
services with regards to service quality.
A Cloud Service Description method to collect
and compare cloud service properties.
6 STAGE OF THE RESEARCH
6.1 Work in Progress
There are currently several activities in progress.
With regards to the requirement elicitation part,
there an in depth literature review on requirements
engineering has been executed to gain insights on
current trends and techniques in this field.
Furthermore first expert interviews have been
made to identify the need and gap for a new
requirement evaluation method for cloud services.
A first identification and analysis on different
mapping candidates like AHP, Fuzzy AHP, Graph
matching, Ontology, Rule Engine, ELECTRE,
TOPSIS, Statistical methods, term-based
matching and preference matrix has been done.
Currently a list of evaluation criteria are setup to
compare and classify these candidates.
State of the art on cloud brokering approaches. As
result a draft categorisation on different cloud
brokering approaches and cloud service selection
has been made (e.g. service intermediation,
service aggregation, service arbitrage (service
mediation internal vs external)).
DCCLOSER 2016 - Doctoral Consortium on Cloud Computing and Services Science
12
Figure 2: Cloud Brokering Classification.
6.2 Next Steps
After finishing the current work in progress, there are
several further activities planned as follows:
1. Two to three requirement analysis approaches
will be piloted and tested with a set of potential
customers
2. Six mapping candidates will be short listed and
analyses more in detail. Four candidates of this six
options will be implemented and ranked, based on
test data.
3. Conducting a first study on approaches for service
classification and descriptions. Developing a
method to identify, describe and compare
qualitative and quantitative Cloud Services so that
a statement of compliance with the claimed
customer requirements can be made.
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