1. Basic Computer Systems Design
& Architecture
01418114 – Introduction to Computer Science
Prasertsak U., Ph.D
2. Computer Architecture
• Von Neumann Architecture
2
The input unit - moves
data from the outside
into the computer.
The output unit -
moves results from
inside the computer
to the outside
The control unit -acts
as the stage unit to
ensure that all the
other components act
in concert.
The arithmetic/logic
gate unit - performing
arithmetic and logic
operations on data
The memory unit - holds
both data and instructions
3. Memory
Address Contents
00000000 11100011
00000001 01010101
… …
11111100 00000000
11111101 11111111
11111110 10101010
11111111 00110011
3
Memory is a collection of cells, each with a unique physical
address. For example, if the addressibility is 8, and there are 256 cells of
memory, the cells would be addressed as follows:
The bits in address 1111110 are
numbered as follows:
8. Multi-core processor
8
In consumer technologies, multi-core is usually the term used to describe two
or more CPUs working together on the same chip.
23. สถาปัตยกรรมการทางานแบบ Client-Server ใน
ลักษณะ Web Based
• การทางานแบบ Web Based นั้นมีลักษณะการทางานแบบ Client-Server
แบ่งออกเป็น 3 ลักษณะ ได้แก่
▫ 2-Tier Architecture – Application Server + DB
Server รวมอยู่ที่เดียวกัน
▫ 3-Tier Architecture – Application Server และ DB
Server แยกกันอยู่คนละระบบ
▫ n-Tier Architecture - หรือ multi-tier ลักษณะนี้ Application
Server และ DB Server แยกกันอยู่คนละระบบ รวมทั้งมี Frontend
Server เพื่อให้บริการในการจ่ายงานไปยังจุดต่าง ๆ ในลักษณะแบ่งภาระงาน
(Load Balancing) หรือมี Server ให้บริการหลายตัวทางานร่วมกัน
23
31. Introduction to Cloud Computing
(cont.)
• Overview Concept
▫ Package of computing resources, such as computation and
storage
▫ Service individual homes and offices across the country via
the network
▫ Readily available on demand
31
Computing Facilities
(SW/HW/Network)
Access Provide
ProvidersConsumers
Pay for Accessing
32. IT Platform Evolution
• IT Platform Evolution
32
Picture from: Cloud Computing for Dummies
by John Hamrick
33. Introduction to Cloud Computing
(cont.)
• Mobility of Contents
33
Your Desktop
on a Thin Client
Your Desktop
on a SmartPhone
Your Desktop
on an iMac
Your Desktop
on a PC
As you move between devices, your desktop follows
you!
*This slide from: Andre Coetzee in the presentation name “The Future of Technology”
34. Some of the key providers
• .
34
From: Courtesy Gravitant, Inc from Cloud Technology Spectrum
35. Hosted Instances
• Host Instances is the physical representation
of a computer for running on a virtualization
environment.
▫ H/W Configuration on demand (RAM, CPU, HD
space, Network, etc.)
▫ Any OS, Applications
▫ Pay as you use
35
38. Virtualization (cont.)
• Virtualization is the ability to run multiple
operating systems on a single physical system
and share the underlying hardware
resources.*
▫ A Virtual machine (VM) is an isolated runtime
environment (guest OS and applications)
▫ Multiple virtual systems (VMs) can run on a single
physical system
38
*VMware white paper, Virtualization Overview
40. Virtualization (cont.)
• Hypervisor - A hypervisor, a.k.a. a virtual machine
manager/monitor (VMM), or virtualization manager, is a
program that allows multiple operating systems to share
a single hardware host.
▫ Controlling the host processor and resources, allocating
▫ To make sure that the guest operating systems (called virtual
machines) cannot disrupt each other.
40
41. Type of Hypervisor
• Hypervisors in Virtualization
41
Picture from: http://www.cisco.com
43. Benefits of Virtualization in Cloud
Computing
• Consumers don’t need to own hardware
• Resources are rented as needed from Cloud
providers
• The providers allow creating virtual servers
▫ Choose the OS and software to run on each instance
▫ The VM will run on a large server farm
▫ Virtual server can initiate within a minute
• Pay per use
43
44. Software in the Cloud
• Two perspective of software in the cloud*
44
*Source: Software Architecture and the Cloud, Grace A. Lewis, Research, Technology and Systems Solutions
(RTSS) Program, SASI 2012
46. Services Models (cont.)
• Data Privacy
46
*Source: Software Architecture and the Cloud, Grace A. Lewis, Research, Technology and Systems Solutions
(RTSS) Program, SASI 2012
47. What are the services?
• .
47
Picture from: http://info.apps.gov
49. Why isn’t everyone to use cloud?
• The cloud acts as a big black box, nothing inside
the cloud is visible to the clients
• Clients have no idea or control over what
happens inside a cloud
• Clouds are still subject to traditional data
confidentiality, integrity, availability, and
privacy issues, plus some additional attacks
49
51. Disadvantage of Cloud Computing
• Technical Issues
▫ Possible downtime
▫ Lack of support
▫ Inflexibility – Locking into their proprietary application
and format of services
• Security Issues
▫ Prone to attack
▫ How safe is your data?
• Long-running cost – Does the cloud application
have all the features that the software does and if
not, are the missing features important to you?
51