NETWORK DESIGN (REKABENTUK RANGKAIAN) TJ3054

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NETWORK DESIGN (REKABENTUK RANGKAIAN) TJ3054

• LECTURER KHAIRUL NAJMY ABDUL RANI
• ROOM NO STM 201
• OFFICE PHONE NO 04-928 3724
• E-MAIL ADDRESSES najmy_at_e-web.uum.edu.my
• OR
• 
  khairul_najmy_at_yahoo.com
• HOMEPAGE http//www.angelfire.com/mo3/najmy

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Overview of computer networking

• What is a computer networking?
• An interconnected collection of autonomous
  computer.
• 2 or more computers are said to be interconnected
  if they are able to exchange (transmit/receive)
  information.
• Autonomous means that acting independently.
• What is a distributed system?
• The existence of multiple autonomous computers,
  which are not visible to the user.
• The distinction between CN and a DS lies with the
  SW (NOS) rather than with the HW
• Why does a computer networking necessary?
• For organizations Resource/Info. sharing, Saving
  cost, Communication medium (audio/video
  conferencing/net meeting), high reliability,
  security, scalability etc.
• For society Remote access, Person-to-Person
  communication (e-mail/messenger/chat),
  audio/video conferencing etc.

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Overview of computer networking

• Computer networking can be classified based on
  type of transmission technology and scale.
• 2 types of transmission technology, which are
• 1 Broadcast Network 2 Point-to-Point
  Network.
• Broadcast Network have a single communication
  channel that is shared by all the network
  devices.
• Broadcasting A packet is transmitted, received
  and processed by each network machines/devices.
• Multicasting A packet is transmitted, received
  and processed by a subset of the network
  machines/devices (e.g. stmnet, studnet etc.)
• Point-to-Point Network consist of many
  connections between individual pairs of machines.

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Overview of computer networking

• Computer networking scale
• Local Area Network (LAN) Privately owned
  networks within a single building or organization
  or campus of up to a few kilometers in size. (10
  m to 1 km inter-processor distance).
• Metropolitan Area Network (MAN) A bigger version
  of LAN and normally used similar technology
  covering a group of nearby corporate offices/ a
  city either private or public (up to 10 km
  inter-processor distance).
• Wide Area Network (WAN) Spans a large
  geographical area, often a country or continent
  (100 km to 1000 km inter-processor distance).
• Wireless Networks Apply antennas, telephone with
  analog modem and Cellular Digital Packet Data
  (CDPD) service. Emerging technology Bluetooth,
  GSM and GPRS.
• Internet a collection of homogonous
  interconnected networks.

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Overview of computer networking

• Vital CN hardware devices includes host
  computer, front-end processor (FEP),
  modulator/demodulator (modem), and terminal.
• Host computer Center computer/processor within
  a large data communication system. It can be a
  mainframe or a minicomputer or a microcomputer.
• FEP is a special purposed computer, which can be
  programmed to control and process data in a
  network. It can be either a non-programmable and
  hardwired communication control unit OR a
  programmable device operating as a communication
  input/output and processor. FEP components are
  channel interface, SW, and line interface unit.
  FEP purposes are offloading certain
  processing/controlling data from host computer to
  a programmed processor, comm. line control, error
  control, multiplexing, converting protocol/code
  and etc.

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Overview of computer networking

• Modem transforms digital electrical pulse
  (generated by computer/terminal) to analog signal
  before being transmitted via analog voice grade
  circuit and vice versa.
• Terminal is a input/output HW located at the
  communication circuit end points. It can be
  microcomputer or workstation or video terminal or
  teleprinter terminal or dumb/intelligent terminal
  and etc.
• Other necessary HW devices that make network
  becomes faster, more reliable and more secure are
  MUX, protocol converter, HW encryption devices,
  intelligent controller, line adapter and etc.
• HW equipments that are commonly used in LAN are
  server, repeater, bridge, router, gateway, and
  cabling.

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Overview of computer networking

• Several issues have to be touched when discussing
  network SW, which is highly structured.
• Protocol hierarchies
• Network is arranged on the layer basis. Every
  layer will give services to its upper layer.
  Every layer communicate with its peer layer (same
  level) at other computer. In this case, a
  protocol (an agreement on how peer communication
  should be made) is required.
• Interface and Services
• Entity Active element in each layer.
• SAP The point where service can be obtained.
• Types
• Connection-oriented Establish, use and release.
• Connectionless Each packet is routed
  independently.
• QoS
• Reliable (acknowledged) OR Unreliable (not
  acknowledged)

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Overview of computer networking

• 2 reference models Open Systems Interconnection
  (OSI) and Transmission Control Protocol/Internet
  Protocol (TCP/IP).
• The OSI deals with connecting open systems (open
  for comm. with other systems).
• The OSI has 7 layers
• Physical mechanical, electrical, functional,
  procedural
• Data link error flow control intermediate
  node
• Network routing, switching, network addressing
• Transport error flow control, packetizing
  end-to-end
• Session establish communication
• Presentation format, compression, encryption
• Application application protocols

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Overview of computer networking







Aplikasi
Presentation
Session
Transport
Network
Data Link
Physical
switching
Electrical voltage
Format data
Hantar mel
physical port
Mod dialog
Flow control
Signal mana hantar dulu
addressing
encription
compression
Berapa laju hantar electrical voltage
Error control
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(No Transcript)
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Overview of computer networking

• The OSI principles
• Each layer can be implemented independently
• Each layer communicates with its peer layer (same
  level)
• Each layer needs service provided by bottom layer
  esp. related to primitive functions.
• In the real world
• There is almost no OSI product.
• In LAN, the 2 most bottom layer used LAN
  standard.
• In WAN, the 3 most bottom layer used X.25, ATM
  and FR

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Overview of computer networking

• TCP/IP has 4 layers
• Network interface/physical communication
  Connects the network using some protocol so it
  can send/receive IP packet over it.
• Internet (IP) Permits hosts to injects packet
  into any network and have them travel
  independently to the destination. This layer
  defines an official packet format and protocol
  known as Internet Protocol (IP).
• Transport (TCP/UDP) Allows peer entities on the
  source and destination hosts to do conversation.
  Transmission Control Protocol (TCP) is a reliable
  connection-oriented protocol that allows a byte
  stream originating on one machine to be delivered
  without error to any other machine in the
  Internet. User Datagram Protocol (UDP) is an
  unreliable connectionless protocol that do not
  want TCP sequencing or flow control.

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Overview of computer networking

• Application Contains all the higher level
  protocols, such as virtual TELNET, FTP, SMTP,
  POP3, DNS, HTTP and etc.

Application
NetBios
NetBuei
Physical network
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
TCP/UDP
IP
Physical Communication
SNA IPX/ SPX Apple-Talk
OSI
TCP/IP
MS Net
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Overview of computer networking

• Standard can affluence the current network design
  and implementation, such as tackling problems
  related to HW and SW.
• Standard are usually enacted/regulated by
  vendors, users and ISPs OR NSPs.
• Standard are usually drafted by certain
  committee, which some of the members are vendor
  representatives
• Standard can be either de jure or de facto.
• de jure is being enacted by formal/official
  bodies, such as IEEE, ISO, ANSI etc.
• de facto is being established by informal
  organization, such HW/SW manufacturers like
  Microsoft, IBM etc.
• ISO is being represented by 90 countries dealing
  with a lot of standard subjects.

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Intro. of system approach in network design

• Actually, there are a lot of approach types can
  be made in designing a new network or in
  upgrading an existing network.
• In this course, the system approach is being
  chosen to design a network or to upgrade an
  existing network.
• The system approach can be used by network
  designer in 1 planning a new data
  communication network 2 troubleshooting or
  upgrading the performance of a current network
  3 planning a public data network.
• In designing a network, all the affluence factors
  and limitations/problems should be clarified and
  highlighted their effects on the network
  performance.
• The key of success starting from a good and
  effective planning particularly, based on
  fulfilling the system user interface requirement

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Intro. of system approach in network design

• Currently, network designer usually emphasizes on
  user application system. In this case, 2 types
  of network user should be classified, which are
  organization management (e.g. manager/director/emp
  loyer) and individual user (e.g.
  employee/subordinate).
• Manager needs a reliable network so that they
  believe whatever messages that they receive.
• User needs a consistent/stable network so that
  they can keep maintaining/upgrading their
  productivities.
• There are 13 basic steps used in network design.
• Feasibility Study
• The main purpose is to improve the current
  network or to build entirely a new network for
  organization/public.

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Intro. of system approach in network design

• Feasibility Study (Continued)
• The responsibility is to define clearly the
  problem existed and make it as (a) written
  document. In the document, highlight the
  problems, possible root causes, possible counter
  measures (solutions) that can be offered and the
  objective/benefits of building a new network.
  Besides, state also the complete and realistic
  costs for a newly designed network or accurate
  costs/benefits comparison for an upgraded
  network.
• Prepare a Network Design Plan(s)
• The main purpose is to provide a framework(s) for
  the network design plan. Ensure that the plan
  meets the requirements. Identify also possible
  constraints. Besides, enlist functions that
  newly upgraded/designed network can perform.

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Intro. of system approach in network design

• Understand the current/existing network
• Try to know fully attributes of existing network
  system, such as operational functionality and HW
  (CPU type, memory size and configurations), SW
  (type applications and network drivers/NOS),
  protocols and standards, and operational support
  methods. Besides, enlist some proposed network
  application for future use. If possible put
  written ideas in terms of notes/DFD/flowchart.
• Define the network requirement
• The purpose is to determine the what in the
  development of a new network and to describe
  attribute the network must contain.
  Conceptually, identify inputs, such as user
  needs, organizational needs, existing systems,
  regulations, and environment politics in order to
  draw out the network requirements and
  constraints. In details, review the org. long
  and short term plan.

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Intro. of system approach in network design

• Also, simulate the circuit capacity, reliability
  and processing time (response time/queuing
  theories). If possible, highlight future
  requirement(s) that may be uncovered for now.
• Define the geography scope
• The purpose is to identify the physical location
  that must be interconnected by the newly designed
  or upgraded network. There are 4 basic levels in
  mapping the network, which are International,
  Country, State/City, and Local Area/Facility.
• Analyze the message
• The purpose is to identify msg. char., no. of
  msg. and how to estimate volume of message. This
  step can be done simultaneously with step no. 5
  above. The output is a list of msg. With no. of
  char. per msg., network link traffic table.

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Intro. of system approach in network design

• Calculate the network traffic and circuit loading
• The purpose is to calculate the circuit capacity
  that is needed for traffic based on no. of char.
  per msg. no. of msg. delivered per given period
  of time. Therefore, needs to calculate the
  response time / turnaround time. RIT MIT APT
  MOT. Besides, it is possible to show the
  circuit capacity req. for each link. The output
  is the documented of traffic analysis (msg.
  total of char. per day).
• Identify network control and security
• The purpose is to control and protect info. from
  various threats, such as errors omissions, msg.
  Loss/damage, disasters, poor error handling,
  viruses/worms, unreliability etc. Use ctrl
  spreadsheet to identify, prepare document and
  re-evaluate all the ctrl point within a network.
  The output are ctrl spreadsheet, list of threats
  def. list of ctrl methods performed.

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Intro. of system approach in network design

• Design network configuration
• The purpose is to configure the network based on
  network goals/objectives.The ckt. config. is done
  btw. The user and host computer. The result
  depends on node/terminal and SW/HW changing. The
  output is the network config. maps/layouts and
  list of network goals.
• Consider the SW selection
• The purpose is to overcome the limitation
  resulted by terminal usage and diff. types of SW
  used thru the using of protocol
  converter/router/gateway. The output is the
  details of network config. Either it is PTP or
  Multiplexed or Multidropped or Packet switched or
  combinations of above. Besides, there should be
  a description of protocol selected as well as
  WAN/LAN SW documentation.

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Intro. of system approach in network design

• Consider the HW selection
• The purpose is to get all the HW required. The HW
  of network can be categorized as transmission
  media and internetworking devices.The output is
  the layout and the config. (multidrop/multiplex,
  etc.) showing all the linked nodes.
• Calculate the cost required
• The purpose is to estimate the cost of
  building/upgrading a network and to review the
  complexity of costing on the chosen network
  configuration. A lot of techniques can be used
  to estimate the cost, such as network cost
  analyzer, cost/benefit analysis, voice grade
  leased circuit cost, dial-up circuit cost,
  wideband analog circuit cost, digital circuit
  cost, T-carrier circuit cost, pkt sw. cost, HW
  cost, and further design cost.

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Intro. of system approach in network design

• Calculate the cost required
• The network cost generally can be classified into
  two groups, which are direct cost and indirect
  cost. Direct cost includes processor/server,
  comm. devices, common carrier line tariffs,
  SW/NOS, spare part cost, and maintenance cost.
  Indirect cost will be personnel training and
  disruption of normal activities. The output is a
  report of network expenditure generated by
  network cost analyzer.
• Implement the new network
• There will two subtasks, which are selling the
  proposed network to mgmt. or to client/user and
  implementing the network. Selling the network
  can be done orally to top mgmt. There are 4Ps
  techniques in implementing the network that are
  Pilot, Phased, Parallel, and Plunge.