Transcript Rapidly Changing World of Information Technology

Rapidly Changing World of
Information Technology
William R. Mussatto
CyberStrategies, Inc.
[email protected]
Topics
Fundamental Business Realities
Evolution of I/T
Role of I/T Today
Client/Server Computing
The Impact of the Internet
Fundamental Business
Realities
Global Market
Rapid Change
Leadership
low-cost or high-value
Jack Welch and GE
Relationships
partners and suppliers
Segmenting Customers
Fundamental Business
Realities
More Demanding Customers
Today, customers are …
more likely to be educated
enjoying higher standard of living
more sophisticated in their use of I/T
I/T enables more customization and
personalization
Evolution of I/T
Limited Role in Past
calculators and adding machines
accounting and finance
MIS glass house
Engineering
Led to Islands of Information
Evolution of I/T
Centralized
Distributed
Functional Stovepipe
Hierarchies
Cross-Functional
Teams
Reactive
Proactive
Stable, Predictable
Conditions
Dynamic, Unpredictable
Conditions
Loyalty, Seniority
Performance
Standalone
Networked
Evolution of I/T
Computing

Telecommunications
Central Nervous System
Role of I/T Today
Ubiquitous Communications and
Productivity Infrastructure
Key Enabler of Business Critical Processes
Becoming More Aligned with Business
Objectives
must understand fundamental business
realities
CIOs reporting to COOs not CEOs
Client / Server Computing
Definitions
Examples
Communications Protocols
Definitions
Preliminaries
http://www.whatis.com/
Distributed Computing
distributing computational capability and
data over physically separated computers
usually connected via a network
network may be intermittent.
Definitions
Distributed Computing
Client / Server
Distributed Computing Environment (DCE)
• Open Software Foundation (OSF)
Remote Procedure Calls (RPC)
TCP/IP Berkeley Sockets
Distributed Objects
Object Management Group CORBA
• Common Object Request Broker Architecture
Java Remote Method Invocation (RMI)
Microsoft C# (this week).
Definitions
Client / Server
Client
makes request
initiates communication
may have a GUI and human
but not always
Server
fulfills request
passively waits for requests
usually multitasking machine
Definitions
Client / Server
Sometimes “Client” refers to the
host
platform
machine (often a desktop machine)
but often refers to the
client-side software
examples: Netscape Communicator, Eudora
Definitions
Client / Server
The Server often controls access to
shared resources such as
file systems (disks, tapes, etc.)
printers
shared communications facilities
email server
Same ambiguity applies to term “Server”
as to “Client”
Definitions
Client / Server
Fat Clients (aka Rich Clients)
full-featured, large applications
use servers as data servers
not much computational power on the
server side
Thin Clients
small applications
downloaded from the network
relies on computational power of server
Definitions
Client / Server
Fat Client Example
Web Browser
Eudora
Visio
Thin Client
HTML pages and Java applets
JavaScript applications inside of HTML
pages
note dependence on fat client (i.e., the
browser)
Definitions
TCP / IP Berkeley Sockets
Defined in late 70’s early 80’s
Shipped with versions of Berkeley Unix
in early 80’s (1982)
endpoints in connections
Transport Layer
like Unix file descriptors and pipes (but 2way)
Definitions
TCP / IP Berkeley Sockets
Five Basic Attributes of a Socket
Connection
Local Port (chosen by OS on client side)
Local IP Address
Remote Port
Remote IP Address
Protocol (“tcp”, “udp”, etc.)
Each Connection Has Own 5-tuple
Definitions
TCP / IP Berkeley Sockets
Server Listens on (Well-Known) Port
Clients Attempts Make a Connection
Server Accepts the Connection
Server Receives Request from Client
Server Interprets Request
performs some action
Sends Response to Client
Shuts Down the Connection
Definitions
Distributed Objects
Object Management Group (OMG) CORBA
Common Object Request Broker Architecture
ORB = Object Request Broker
brokers components between clients and servers
client does not need to know the where the
server is or how its interface works
like a registry
Examples
Distributed Objects
Application Servers / Frameworks
Three-Tier Architecture
Examples
IPlanet Application Server (IpAS)
Oracle Application Server
IBM WebSphere Application Server
Bluestone’s Saphire/Web (R) Application
Server Framework
Examples
Distributed Objects: NAS
2-tier
Multi-tier
Examples
Distributed Objects: NAS
Summary
Client / Server
A Type of Distributed Computing
most common type
Client Initiates Request
Server Passively Waits, then Responds to
Client Request
Berkeley Sockets
most widely used mechanism facilitating
client / server computing on the Internet
Impact of the Internet
Internet Technologies within the
Enterprise ==> Intranet
Studies Show 1000% ROI on Intranets
New Flow of Information Into and Out of
the Enterprise
Security a Major Factor
VPNs