Architecture and Infrastructure

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17 Φεβ 2014 (πριν από 3 χρόνια και 8 μήνες)

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Dr. Chen,
Management Information Systems

Chapter 6

Architecture and
Infrastructure

Jason C. H. Chen, Ph.D.

Professor of MIS

School of Business Administration

Gonzaga University

Spokane, WA 99258

chen@jepson.gonzaga.edu

Dr. Chen,
Management Information Systems

Learning Objectives


Understand how strategy drives architecture, which
then drives infrastructure.


Identify and define the three configurations for IT
architecture.


Define how business goals can be translated into IT
architecture and then into infrastructure.


Know the different types of frameworks used to
design and build the IT architecture and infrastructure.


Understand the importance of knowing the details of
the existing architecture and infrastructure of the
organization.

Dr. Chen,
Management Information Systems

Real World Examples


Over the past 10 years Valero Energy (gas/oil refiner) has
experienced
hypergrowth
.


Revenue has grown from $29 to $90 billion.


This growth came with a mixture of disparate IT systems and
applications.


Difficult and expensive to manage.


Not easily integrated into ERP system.


IT architecture needed to be redesigned to meet future needs.


Flexible in design and able to grow with the company.


An SOA system was selected: SAP R/3 ERP.


90 service components were built on the SAP platform.

Dr. Chen,
Management Information Systems

Real World Examples (Cont.)


The results were dramatic.


New applications made operations more efficient and
effective.


Development costs were kept low.


One application saved the company $500K in fees.


The new application provides visibility to the tankers.


Communications with employees reduced scheduling
conflicts.


Managers were able to control the loading and
unloading of tankers, which

was previously
unavailable.

Dr. Chen,
Management Information Systems

From Vision to Implementation


Architecture

translates
strategy

into
infrastructure

(Figure
6.1).


The architect develops plans based on a vision of how
the customer will use the system (or in the example a
house), which is a blueprint of the company’s systems.


This IT architecture “
blueprint
” is used for translating
business strategy into a plan for IS.


The
IT infrastructure
is everything that supports the flow
and processing of information (e.g., hardware,
software, data, and networks).


Dr. Chen,
Management Information Systems

Figure 6.1 From abstract to concrete


building vs. IT.

Abstract
Concrete
Owner’s
Vision
Architect’s
Plans
Builder’s
Implementation
Strategy
Architecture
Infrastructure
Information
Technology
Building
© John Wiley & Sons

Dr. Chen,
Management Information Systems

The Manager’s Role


The manager’s role is to:


Understand what to expect from IT architecture and
infrastructure to make full and realistic use of them.


Effectively
communicate

the business vision to IT
architects and implementers.


Modify the plans if IT cannot realistically support them.


Be involved in the
decision
-
making
process.


Dr. Chen,
Management Information Systems

From Strategy to Architecture


The manager must start out with a
strategy
.


Use the strategy to develop more specific
goals

(Figure 6.2).


Business requirements
for each goal
must be fleshed out in order to
provide the architect with a clear picture of what IS must
accomplish.


The manager must work with the
IT architect
.


Translate the business requirements into a more detailed view of the
systems requirements, standards, and processes.


The architectural requirements include considerations such as:


Data demands, process demands, and security objectives.


The IT architect takes the architectural requirements and designs
the IT architecture.

Dr. Chen,
Management Information Systems

From Architecture to Infrastructure


This stage entails adding more detail to the
architectural plan

such as:


specifying hardware, data, networking, and software(Figure 6.2).


Decisions are made about how to implement these specifications:


What hardware, software, storage, interface, network, etc. to use in the
infrastructure.


Components must be assembled in a coherent pattern according to the blueprint in order
to have a viable infrastructure.


Infrastructure has several levels:


Global level


Interorganizational

level


Application
-
level


Infrastructure also refers to the
platform
.

Dr. Chen,
Management Information Systems

Figure 6.2 From strategy to business requirements.

© John Wiley & Sons

Dr. Chen,
Management Information Systems

A Framework for the Translation


The framework for transforming business strategy into
architecture and then into
infrastructure

should consider
basic components (Figure 1.8):


Hardware


physical components.


Software


programs.


Network


software and hardware.


Data


numbers and text.


Understanding the technology behind each component
of the infrastructure and the technical requirements of
the architecture is a much more complex task.





Dr. Chen,
Management Information Systems

Figure 6.3 Infrastructure and architecture analysis framework with sample questions.

Dr. Chen,
Management Information Systems

A Framework for Translation (Cont.)


Managers must begin with an overview that is
complete and delivers a big picture.


Figure 6.3 entails questions that typify those asked in
addressing architecture and infrastructure issues associated
with each component.


The framework asks three types of questions that must
be answered for each infrastructure component:


What is the specific type of technology?


Who is involved (individuals, groups, departments)?


Where is everything located?


Figure 6.3 shows the connections between the
business strategy and the infrastructure.


Dr. Chen,
Management Information Systems

Common IT Architecture

Configurations


Three common configurations of IT architecture
(Figure 6.4).


Centralized
architecture
:

everything is purchased, supported,
and managed centrally via a data center.

o
A large data center with a mainframe and a number of legacy mainframe
environments.

o
Many computers are linked together to form a centralized IT core that operates very
much like the mainframe, providing the bulk of IT services necessary for the
business.

Dr. Chen,
Management Information Systems

Common IT Architecture

Configurations (Cont.)


Decentralized architecture
arranges the hardware, software, networking, and data
in a way that distributes the processing and functionality between multiple small
computers, servers, and devices.


Relies heavily on a network to connect them.


Utilizes numerous servers located in different physical locations.


A server
-
based architecture.


Service
-
or
iented Architecture
(SOA) utilizes relatively small chunks of
functionality available for many applications or
reuse
.


Useful for building applications quickly.


Offers managers a modular and componentized design that is easily modifiable.


SOA
utilizes
software
-
as
-
a
-
service

(
SaaS
) or Web services.

Dr. Chen,
Management Information Systems

Figure 6.4 Common architectures.

© John Wiley & Sons

Dr. Chen,
Management Information Systems

Centralized Versus Decentralized Architectures


A manager must be aware of the
trade
-
offs

when considering centralized
versus decentralized architectures.


Decentralized

architectures

are more modular than centralized
architectures.


Additional servers can be added with relative ease and provide greater
flexibility for adding clients with specific functionality for specific users.


Decentralized organizational governance, such as that associated with the
networked organization structure, is consistent with decentralized
architectures.

Dr. Chen,
Management Information Systems

Additional Infrastructures


Peer
-
to
-
peer



allows networked computers to share resources without a central server.


Wireless

(mobile)


allows communication from remote locations using a variety of
wireless technologies.


Web
-
based


significant hardware, software, and possibly even

data elements that

reside on the Internet.


Offers greater flexibility when used as a source for
capacity
-
on
-
demand

or for

additional
processing capability for a fee.


Bring Your Own Device
(BYOD)
-

employees bring their own devices and connect to
enterprise systems.


Raises issues with capacity, security, and compatibility.


Consumerization of IT



the push for employees and customers to use their own devices
to
access

corporate

systems

and the
ensuing

issues to
make

them

work
.

Dr. Chen,
Management Information Systems

From Strategy to Architecture to Infrastructure


The process of converting
strategy

to
architecture

to
infrastructure
:


Define the strategic goals.


Translate goals into business requirements.


Specify architectural requirements.


Translate specs into hardware, software, data protocols,
interface designs, and other components that will make up
the infrastructure.


Figure 6.5 lists questions raised when applying the framework to
TennisUp’s

architecture goals and related infrastructure.


Figure 6.6
lists

possible infrastructure components.

Dr. Chen,
Management Information Systems

Component

What

Who

Where

Architecture

Infrastructure

Architecture

Infrastructure

Architecture

Infrastructure

Hardware

What kind of
supplemental
server capacity will
the new EDI
transactions
require?

Will
TennisUp

s

current dual CPU
NT servers handle
the capacity, or will
the company have
to add additional
CPUs and/or disks?

NA

Who is
responsible for
setting up
necessary
hardware at the
partner site?

Where does
responsibility for
owning and
maintaining EDI
hardware fall
within
TennisUp
?

Which hardware
components will
need to be replaced
or modified to
connect to the new
EDI hardware?

Software

What parts of
TennisUp

s
software
architecture will
the new
architecture affect?

Will
TennisUp

s

current Access
database interface
adequately with the
new EDI software?

Who knows the
current software
architecture well
enough to manage
the EDI
enhancements?

Who will do any
new SQL coding
required to
accommodate the
new software?

NA

Where will software
patches be required
to achieve
compatibility with
changes resulting
from new software
components?

Network

What is the
anticipated volume
of transactions
between
TennisUp

and its
manufacturing
partners?

High volume may
require leased lines
to carry transaction
data; dial
-
up
connections may
suffice for low
volume.

Who is responsible
for additional
networking expense
incurred by partners
due to increased
demands of EDI
architecture?

NA

Where will
security concerns
arise in
TennisUp

s

current network
architecture?

Where will
TennisUp

house
new networking
hardware required
for EDI?

Data

Will data formats
supporting the new
architecture be
compatible with
TennisUp

s

existing formats?

Which formats must
TennisUp

translate?

Who will be
responsible for
using sales data to
project future
volumes to report to
the manufacturing
partner?

Who will be
responsible for
backing up
additional data
resulting from
new architecture?

Where does the
current
architecture
contain potential
bottlenecks given
the changes
anticipated in
data flows?

Does the new
architecture require
TennisUp

to switch
from its current
10Base
-
T Ethernet
to 100Base
-
T?

Figure 6.5 Framework application to
TennisUp
.

Dr. Chen,
Management Information Systems

Hardware

Software

Network

Data

3 servers:



Sales


Manufacturing


Accounting


Storage systems


ERP system with
modules for
:


Manufacturing


Sales


Accounting


Inventory


Enterprise Application
Integration (EAI)
software



Cable modem to ISP


Dial
-
up lines for
backup


Routers

Hubs

Switches

Firewalls


Database:



Sales


Manufacturing


Accounting

Figure
6.6
TennisUP’s

infrastructure
components.

© John Wiley & Sons

Dr. Chen,
Management Information Systems

Architectural Principles


Based on a set of principles or fundamental beliefs
about how the architecture should function.


Architecture

principles

must be consistent with both
the enterprise values as well as the technology used in
the infrastructure.


The number of principles vary widely.


Principles should define the desirable behaviors of the
IT systems

and the role of the organization(s) that
support it.


Sample architectural principles (Figure 6.7).

Dr. Chen,
Management Information Systems

Enterprise Architecture


The “
blueprint
” for all IS and its interrelationships in the firm.


Specifies how IT will support
business processes
by identifying:


core processes of the company and how they will work
together.


how the IT systems will support the processes.


the standard technical capabilities and activities for all parts
of the enterprise.


Guidelines for making choices.


Four key elements:

1.
Core business processes.

2.
Shared data.

3.
Linking and automation technologies.

4.
Customer groups.

Dr. Chen,
Management Information Systems

Figure
6.7 Sample architectural principles.

Dr. Chen,
Management Information Systems

Enterprise Architectures (Cont.)


TOGAF

(The Open Group Architecture Framework)


Includes a methodology and set of resources for
developing an enterprise architecture.


Zachman

F
ramework


Determines architectural requirements by providing a
broad view that guides the analysis of the detailed view.


Building an enterprise architecture is a joint
exercise with business leaders and IT leaders.


Business processes
are designed concurrently with
IT
systems
.


Dr. Chen,
Management Information Systems

Virtualization and Cloud Computing


Virtualization infrastructure
-

computing capabilities, storage, and
networking provided by a third party or group of vendors,
usually over the Internet or through a private network (e.g.,
virtualized desktop).


Includes servers, storage, backup, network, and disaster recovery.


Enables resources to be shared and allocated as needed by the user.


Makes maintenance easier since resources are centralized.


Cloud computing
-

virtual infrastructure provided over the
Internet.


SaaS

(
Software as a
S
ervice
)
,
PaaS

(Platform as a Service), and
IaaS

(Infrastructure as a Service).


A
cloud

is a large cluster of virtual servers or storage devices.


Dr. Chen,
Management Information Systems

Virtualization and Cloud Computing

(Cont.)


Users purchase
capacit
y
-
on
-
d
emand
.


Utility computing
-

computing capability is purchased on an as
-
needed basis.


Examples of applications in the cloud:


Salesforce.com, Facebook, Gmail, Windows Azure, Apple iTunes, and LinkedIn.


Benefits of virtualization and cloud computing:


Consolidated physical servers.


Reduced physical costs of the data center.


No upgrading.


No maintenance, power, or electricity costs.


No need for physical space or storage servers.


Increased speed of attaining additional capacity (provisioning).

Dr. Chen,
Management Information Systems

Virtualization and Cloud Computing




Managerial Considerations


Managers must also understand the
risks
of a third
-
party
supplier.


Retooling existing applications for the cloud’s infrastructure.


No established

standards for virtual infrastructure.


Applications not porting easily from one vendor’s infrastructure to
another’s.


As coordination costs drop and platforms in the
cloud open up, cloud computing utilization will
increase.

Dr. Chen,
Management Information Systems

Understanding Existing Architecture


The primary reason to base architecture on an
organization’s strategic goals is to allow for inevitable
future changes to:


the business environment.


organization.


IT requirements.


the technology itself.


Future consideration for
IT architecture
should include:


analysis of the existing architecture.


the strategic time frame.


technological advances.


financial constraints.


Evaluate the
IT requirements
of an evolving
business
strategy
against current
IT capacity
.

Dr. Chen,
Management Information Systems

Understanding Existing Architecture


-

Managerial Considerations


Relevant questions for managers:


What IT architecture is already in place?


Is the company developing the IT architecture from scratch?


Is the company replacing an existing architecture?


Does the company need to work within the confines of an existing
architecture?


Is the company expanding an existing architecture?


A strong
business strategy
is a prerequisite for
IT
architecture
design, which is a prerequisite for
infrastructure

design.

Dr. Chen,
Management Information Systems

Additional Managerial Considerations


Managers can derive the most
value

and incur minimal loss when working
with legacy
architectures

and
infrastructures

by objectively analyzing:

1.
the existing architecture and infrastructure.

2.
the strategy served by the existing architecture.

3.
the ability of the existing architecture and infrastructure to further the
current strategic goals.


Managers must ensure that the architecture will satisfy their
strategic

requirements

and that it is modern and efficient.

Dr. Chen,
Management Information Systems

Assessing Strategic Time Frame



Understanding the life span of
IT infrastructure
and
architecture

is critical.


Strategic time frames
depend on industry
-
wide factors

such as:


the level of commitment to fixed resources, maturity of the industry,
cyclicality, and barriers to entry.


Business strategy planning horizon.


Management reliance on IT and on the specific rate of advances affecting IT.


Design with maximum
flexibility

and
scalability

to ensure handling of future
business changes.

Dr. Chen,
Management Information Systems

Assessing Technical Issues: Adaptability


Can the architecture adapt to
emerging technologies
?


Must be able to handle and absorb technological advances.


Innovations in storage capacity and computing power.


Unexpected technological leaps.


Consider both hardware and software.


Guidelines for planning adaptable
IT architecture
and infrastructure:


Plan for applications and systems that are independent and
loosely coupled rather than monolithic.


Set clear boundaries between infrastructure components.


Provide access to all users when it makes sense to do so
(e.g. security concerns) when designing a network
architecture.

Dr. Chen,
Management Information Systems

Assessing Technical Issues: Scalability


Refers to how well an
infrastructure

component can
adapt to increased, or in some cases decreased,
demands.


A
scalable network system
should start with just a
few nodes but have the ability to easily expand to
thousands of nodes.


It is important to analyze the impact of
strategic
business decisions
on IT architecture and
infrastructure.


Ensure a
contingency plan
exists for potential
unexpected effects of a strategy change.

Dr. Chen,
Management Information Systems

Assessing Technical Issues: Standardization


Hardware and software use a common
standard
.


Easier to plug into infrastructure or architecture (e. g.,
Microsoft Office suite).


Interfaces often accompany the standard.


It is easy to move data between systems.

Dr. Chen,
Management Information Systems

Assessing Technical Issues:

Maintainability



The manager needs to ask:


How easy is it to
maintain

the infrastructure?


Are replacement parts available?


Are support services available?


Maintainability is a key
technical

consideration.


The complexity of the systems increases the number of things that
can go wrong, need fixing, or need replacing.


Should a technology become obsolete, costs
skyrocket for parts and expertise.

Dr. Chen,
Management Information Systems

Assessing Technical Issues: Security


Major concern for
business

and
IT managers
.


Must protect key
data

and process elements of the
IT infrastructure
.


Extends outside the boundaries of the company (e.g., customer data).


Innovations
encrypt

or disguise sensitive information, financial information, and
business information.


Securing assets in a highly centralized, mainframe architecture means building
protection around the centralized core.


Decentralized, server
-
based architecture is more difficult to secure due to the
dispersion of servers.


Web
-
based SOA
that utilizes
SaaS

and
capacity

on

demand

raises a whole new
set of security issues.

Dr. Chen,
Management Information Systems

Assessing Technical Issues: Security

(Cont.)


The
security of networks
continues to improve
through:


innovations such as
authentication
, passwords, digital signatures,
encryption, secure servers, and firewalls.


new schemes for security such as securing specific assets instead
of just securing the perimeter of a system.


Managing security is often a matter of managing
risk
.


Assessing the likelihood of a
breach

and the cost of that breach in
terms of loss and recovery.

Dr. Chen,
Management Information Systems

Assessing Financial Issues


IT infrastructure components should be evaluated based on their expected
financial
value
(Figure 6.8).


Payback

from IT investments is difficult to quantify.


Takes the form of increased productivity, increased interoperability with business
partners, improved service for customers, etc.


Focus on how IT investments enable business objectives rather than on their
quantitative returns.


Quantify returns on infrastructure investments by:

1.
Quantifying costs.

2.
Determining the anticipated life cycles of system components.

3.
Quantifying benefits.

4.
Quantifying risks.

5.
Considering ongoing dollar costs and benefits.

Dr. Chen,
Management Information Systems

Figure
6.8
TennisUp’s

managerial considerations.

Dr. Chen,
Management Information Systems

Chapter 6
-

Key Terms

Architecture

(p. 169)
-

provides a blueprint for translating business

s
trategy into a plan for IS.

Brin
g
-
your
-
own
-
d
evice

(BYOD) (p. 177)
-

employees bring

their own devices and connect to enterprise systems.

Capacity
-
on
-
d
emand

(p. 177)
-

the availability of additional processing

capability for a fee.

Centralized architecture
(p. 173)
-

everything
is purchased,

supported,
and managed
centrally

via a
data
center
to eliminate

the difficulties that come with managing a distributed infrastructure.

Client
(p. 175)
-

a device or software program that requests data and sometimes
instructions from another software program, usually running on a separate
computer.

Dr. Chen,
Management Information Systems

Chapter 6
-

Key Terms (Cont.)

Cloud computing
(p. 183)
-

an architecture based
on services

provided over the Internet.

Consumerization of IT
(p. 177)
-

the drive to port
applications to

personal devices and the ensuing issues to make
them work.

Decentralized architecture
(p. 174)
-

The
hardware, software,

networking, and data
arranged
in a way that
distributes
the processing and
functionality between
multiple small computers, servers, and devices
,
relying
heavily on a network to connect them
together.

Enterprise architecture
(p. 180)
-

the “blueprint”
for all IS and its interrelationships in the firm.

Dr. Chen,
Management Information Systems

Chapter 6
-

Key Terms (Cont.)

Infrastructure

(p. 169)
-

everything that supports the flow and

processing of information in an organization, including hardware,

software, data, and network components.

Peer
-
to
-
peer

(p. 176)
-

allows networked computers to share

resources without a central server playing a dominant role.

Platform

(p. 172)
-

an infrastructure or an underlying computer

system.

Reuse

(p. 174)
-

relatively small chunks of functionality available
for

many applications.


Dr. Chen,
Management Information Systems

Chapter 6
-

Key Terms (Cont.)

Scalable
(p. 188)
-

how well an infrastructure component can
adapt to

increased, or in some cases decreased, demands.

Server
-
based architecture
(p. 174)
-

a decentralized
architecture that uses numerous servers often located in
different physical locations.
Service
-
oriented architecture
(SOA) (p. 174)
-

applications delivered over the Internet.

Standards

(p. 188)
-

rules or principles.

TOGAF

(p. 182) (The Open Group Architecture Framework)
-

a methodology and set of resources for developing an
enterprise architecture.

Dr. Chen,
Management Information Systems

Chapter 6
-

Key Terms (Cont.)

Utility computing
(p. 184)
-

computing infrastructure
available when

needed in as much quantity as needed.

Virtualization

(p. 183)
-

a virtual infrastructure where
software replaces hardware in a way that a “virtual machine”
or a virtual desktop system” was accessible to provide
computing power.

Web
-
based architectures
(p. 176)
-

architectures in which
significant

hardware, software, and possibly even data elements reside
on the Internet.

Web services
(p. 175)
-

services delivered over the Internet.

Dr. Chen,
Management Information Systems

Chapter 6
-

Key Terms (Cont.)

Wireless (
M
obile
)
Infrastructure

(p. 176)
-

allow
communication from remote locations using a
variety of wireless technologies (e.g., fixed
microwave links, wireless LANs, data over cellular
networks)

Zachman

Framework
(p. 182)
-

determines
architectural

requirements by providing a broad view that helps
guide the analysis of

the detailed view.