ITELEC Flashcards
means technology solutions can be built via a service-oriented architecture by connecting up services from different providers
- top of other people other’s platforms.
Rise Of The Services Economy
- to deal with this ever-increasing complexity of our technology landscape will require a move from the standalone solutions of today.
- today, into a world of systems of systems, where
smaller technologies are nested within larger ones which in turn are nested within larger ones in a
plug and play, flexible, modular, service-oriented architecture.
Complexity
increasingly end-users are becoming
producers and to harness this new source
of innovation means closed systems have to
open up; creating APIs and platforms on
which end-users can alter, adapt and
innovate while being supported by the core
technology.
user generated systems
is a group of technologies that are
used as a base or infrastructure
upon which other applications,
technologies or processes are
developed for the end-user
platform
also known as the infrastructure
layer or system software layer, forms
the foundation for running
applications.
Platform Layer
sits on top of the platform layer and
represents the actual software
applications that users interact with
to perform specific tasks
Application Layer
is the quality of dealing with generic
forms rather than specific events,
details or applications.
Abstraction
This is achieved by defining a core
set of building blocks and then
configuring them into different
bundles depending on the context.
Bunding
Platforms are open systems, unlike
traditional technologies that are
simply designed as individual
physical objects that perform a
function, platforms are designed to
be interoperable with other systems,
they will likely have external
applications running on top of them
all of which can not be fully foreseen
by the developers of the platform.
Interoperability
Adaptive capacity and agility are,
and will increasingly be seen as a
key requirement, if not the key
requirement, in the coming decades
Evolution
is a critical aspect of platform
technologies as it serves as a bridge
between different components of a
system, allowing them to
communicate and interact
seamlessly.
Interface
are built on top of the
platform layer and leverage the
underlying infrastructure and
services provided by the platform.
Application
is a fundamental component of
platform technologies, serving as an
intermediary between hardware and
software.
Operating System
refers to the underlying hardware
and networking components that
support the platform and
applications.
Infrastructure
The interface facilitates
communication between different
layers of the platform, allowing
applications to interact with the
operating system and infrastructure
through well-defined interfaces.
Interrelationship/Interoperability
This was from the period of 1940 to
1955.
- This was when machine language
was developed for the use of
computers.
- They used vacuum tubes for the
circuitry
1st Generation:
The years 1957-1963 were referred
to as the “second generation of
computers” at the time.
- ____and ______are
employed as assembly languages
and programming languages.
- Here they advanced from vacuum
tubes to transistors.
2nd Generation:
Combol & Fortan
The hallmark of this period
(1964-1971) was the development of
the integrated circuit.
3rd Generation:
The invention of the
microprocessors brought along the
fourth generation of computers.
- The years 1971-1980 were
dominated by fourth generation
computers. C, C++ and Java were
the programming languages utilized
in this generation of computers.
4th Generation:
These computers have been utilized
since 1980 and continue to be used
now.
5th Generation:
These early computers were
designed, built and maintained by a
single group of people.
- Programming languages were
unknown and there were no
operating systems so all the
programming was done in machine
language. All the problems were
simple numerical calculations.
- By the 1950’s punch cards were
introduced and this improved the
computer system.
The First Generation ( 1945 - 1955 ):
Vacuum Tubes and Plugboards
These machines were known as
mainframes and were locked in
air-conditioned computer rooms with
staff to operate them.
- The Batch System was introduced to
reduce wasted time in the computer.
Transistors and Batch Systems
The third generation operating
systems also introduced
multiprogramming.
- This meant that the processor was
not idle while a job was completing
its I/O operation. Another job was
scheduled on the processor so that
its time would not be wasted.
The Third Generation ( 1965 - 1980 ):
Integrated Circuits and Multiprogramming
- _________ were easy to
create with the development of
large-scale integrated circuits.
The Fourth Generation ( 1980 - Present ):
Personal Computers
Storage Hierarchy Model
- Register
- Cache
- Main Memory
- nonvolatile memory
- Hard-disk driver
- Optical Disk
- Magnetic tapes
any mechanism for controlling
access of processes or users to
resources defined by the OS
Protection
defense of the system against
internal and external attacks.
Security
used when source CPU type
different from target type (i.e.
PowerPC to Intel x86)
- Generally slowest method
- When computer language not
compiled to native code –
Interpretation
Emulation
OS natively compiled for CPU,
running guest OSes also natively
compiled
- Consider VMware running WinXP
guests, each running applications,
all on native WinXP host OS
- VMM (virtual machine Manager)
provides virtualization services
Virtualization
Stand-alone general-purpose
machines
Traditional
Handheld smartphones, tablets, etc.
Client-Server Computing
- Dumb terminals supplanted by smart
PCs
- Many systems now servers,
responding to requests generated by
clients
- Compute-server system provides an
interface to client to request services
(i.e., database)
- File-server system provides interface
for clients to store and retrieve files.
Mobile
Another model of distributed system
- does not distinguish clients and
servers
Cloud Computing
Peer-to-Peer
Delivers computing, storage, even
apps as a service across a network
Cloud Computing
available via Internet to anyone
willing to pay
Public cloud
run by a company for the company’s
own use
Private cloud
includes both public and private
cloud components
Hybrid cloud
one or more applications available
via the Internet (i.e., word processor)
Software as a Service (SaaS)
software stack ready for application
use via the Internet (i.e., a database
server)
Infrastructure as a Service (IaaS)
- servers or storage available over
Internet (i.e., storage available for
backup use)
Platform as a Service (PaaS)
most prevalent form of computers
Real-time embedded systems
The database is on the server
The 2-tier architecture
The back-end server is usually a
very large database (or databases)
- The middle-tier server usually holds
shared applications
(application/business logic)
The 3-tier architecture
Three ways of distributing the
- ‘business logic’
- locate it entirely on the client (fat
client)
- locate it entirely on the server (fat
server)
- split it between the client and server
Locating the business logic
Dividing up the data
- Locating the data
divides an application into logical
layers and physical tiers.
N-tier architecture
consists of a collection of small,
autonomous services.
Microservices architecture
A web front end that serves client
requests
Web-Queue-Worker architecture
For handling the ingestion,
processing, and analysis of data that
is too large or complex for traditional
database systems.
- * For large-scale workloads that
require a large number of cores,
such as image rendering, fluid
dynamics, financial risk modeling, oil
exploration, drug design, and
engineering stress analysis
Big data, Big compute architectures
if the owner of data decides to make
available only to certain people and
no others, the system should
guarantee that release of the data to
unauthorized people never occurs
Confidentiality
unauthorized users should not be
able to modify any data (changing
the data, removing data and adding
false data) without the owner’s
permission
Integrity
nobody can disturb the system to
make it unusable, such as in the
form of denial-of-service attacks that
are increasingly common
Availability
try to steal information passively
- sniff the network traffic and tries to
break the encryption to get to the
data
Passive attacks
try to make a computer program
misbehave
- take control of a user’s Web browser
to make it execute malicious code
Active attacks
clutering systems
symmetric/hot standby
asymmetric/load balancing
archi req
reliable, robust communication between client and server
client-server cooperation
servers control data/services that the client accesses
servers handle conflicting requests
application processing is distributed between client and server
common network attacks
tcp hijacking
dos
ddos
malware
spyware
insider attacks
packet sniffing
exploiting software bugs, buffer overflows
social problem
finding a way into the network
principles
abstraction - dealing with generic form
bunding - bulding blocks
interoperabilit - platforms are open systems
evolution - tech is not static, changes through time
