Network Fundamental

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Network Fundamental

• CPE302 TCP/IP Network Lab 2004
• Dome Potikanond
• Sakgasit Ramingwong

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Network Fundamentals

• Network Terminology
• Bandwidth
• Networking Models

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Networking Terminology

• Data networks
• Sharing data through the use of floppy disks was
  not an efficient (Sneakernet)
• Networking technology could increase productivity
  while saving money
• Avoid duplication of equipment and resources
• Communicate efficiently
• Set up and manage a network

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Networking Terminology

• Data networks
• In the mid-1980s, each company used its own
  network technologies standard
• Difficult to communicate with each other
• One early solution was the creation of local-area
  network (LAN) standards
• MAN Metropolitan Area Network
• WAN Wide Area Network

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Networking Terminology
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Networking Terminology

• Network history
• 1947 solid-state transistor (Barden Brittain)
• 1950s mainframe punched card programs
• 1960s mainframe IC
• 1977 microcomputer (Apple)
• 1981 open-architecture IBM personal computer
  (IBM)
• Mid 1980s share file using modem (P-to-P,
  dial-up) bulletin boards
• 1960s 90s development of WAN for military and
  scientific reasons
• allowed multiple computers to be connected
  together
• Eventually became the internet

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Networking Terminology

• Networking devices
• Equipment that connects directly to a network
• 2 classifications of devices
• End-user devices provide services to users
• Network devices connect end-user devices
  together and allow them to communicate
• End-user devices that provide user with a
  connection to the network are HOST
• Hosts are physically connected to network media
  using Network Interface Card (NIC)

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Networking Terminology

• NIC is also called a Network Adapter
• Notebook NICs are usually the size of a PCMCIA
  card

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Networking Terminology

• Networking devices
• Each NIC has a unique code, call a Media Access
  Control (MAC) address
• MAC address is used to control data communication
  over single-segment network
• Network devices provide transport for the data
• extension of cable connection
• Concentration of connection
• Conversion of data formats
• Management of data transfers

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Networking Terminology

• Networking devices

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Networking Terminology

• Networking devices
• Repeater regenerate analog or digital signal
  distorted due to attenuation
• Hub take a group of hosts and allow network to
  see them as a single unit (segment)
• Bridge convert network transmission data formats
  as well as decide whether it should cross the
  bridge or not?
• Workgroup switch determine data should remain on
  a LAN or not? transfer data only to the
  connection that needs that data
• Router all above also able to connect to a WAN

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Networking Terminology

• Network topology structure of network
• Physical topology actual layout of the wire
• Bus topology
• Ring topology
• Star topology
• Extended star topology
• Hierarchical topology
• Mesh topology

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Networking Terminology

• Network topology

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Network Terminology

• Network topology
• Logical topology how the hosts communication
  across the medium
• Broadcast topology
• Each host sends its data to all other hosts on
  the network medium
• First come, first serve
• Ethernet
• Token passing
• Passing electronic token sequentially to each
  host
• The host that received token is only station can
  send data on the network
• If the host has no data to send, it passes the
  token to the next host
• Token Ring and FDDI

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Network Terminology

• Network topology

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Network Terminology

• Network protocol
• Protocol suites are collections of protocols that
  enable network communication from one host to
  another across network
• A protocol is a set of rules that govern how
  devices on a network communicate
• Protocol determine
• Format
• Timing
• Sequencing
• Error control
• Flow control

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Network Terminology

• Network protocol
• Protocol control all aspects of data
  communication
• How the physical network is built
• How computer connect to the network
• How data is formatted for transmission
• How data is sent
• How to deal with error
• These network rules are created and maintained by
  many different organization and committees
• IEEE Institute of Electrical and Electronic
  Engineers
• ANSI American National Standards Institute
• TIA Telecommunication Industry Association
• EIA Electronic Industries Alliance
• ITU International Telecommunication Union

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Network Terminology

• Local-area networks (LANs)
• Consists of the following components
• Computers
• NIC
• Peripheral devices
• Networking media
• Networks devices
• Some common LAN technologies are
• Ethernet
• Token Ring
• FDDI

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Network Terminology

• LANs

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Network Terminology

• Wide-area networks (WANs)
• WANs are designed to do the following
• Operate over a large geographical areas
• Allow users to have real-time communication
  capabilities with other users
• Provide full-time remote resources connected to
  local services
• Some common WAN technologies are
• Modems
• Integrated Services Digital Network (ISDN)
• Digital Subscriber Line (DSL)
• Frame Relay
• US (T) and Europe (E) Carrier Series T1, E1,
  T3, E3
• Synchronous Optical Network (SONET)

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Network Terminology

• WANs

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Network Terminology

• Storage-area networks (SANs)
• A dedicated, high performance network used to
  move data between services and storage resources
• Allow high-speed server-to-storage,
  storage-to-storage, server-to-server connectivity
• SANs features
• Performance enable concurrent access of disk or
  tape arrays at high speeds
• Availability SANs have disaster tolerance
• Scalability allow easy relocation of backup
  data, file migration and data replication between
  systems

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Network Terminology

• SANs

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Network Terminology

• Virtual Private Network (VPN)
• VPN is a private network
• Constructed within a public network
  infrastructure such as the global internet
• Telecommunicater can access the company network
  through the internet by building a secure
  tunnel between telecommunicaters PC and VPN
  router in the company
• 3 main types of VPNs
• Access VPNs
• Intranet VPNs
• Extranet VPNs

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Network Terminology

• VPN

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Bandwidth

• Measurement
• Basic unit of bandwidth in digital system is bps
  (bits per second)
• But bandwidth and speed are NOT the same

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Bandwidth

• Limitation
• Bandwidth varies depending upon the type of media
  as well as the LAN and WAN used
• Medium
• Twisted-pair copper wire
• Coaxial cable
• Optical fiber
• Air
• The physical differences in the way signals
  travel result in fundamental limitation
• The actual bandwidth of a network is determined
  by a combination of the physical media and the
  technologies

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Bandwidth

• Maximum bandwidths and length limitations

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Bandwidth

• WAN Services and Bandwidths

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Networking Models

• Layer communication
• The information that travels on a network is
  referred to as data or packet
• The method of layering explains how a computer
  network distributes information from a source to
  a destination
• The communication process in computer network can
  be broken into separate layers (steps)
• As the data passes between layers, each layer
  adds additional information that enables
  effective communication with the corresponding
  layer on the other computer.

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Networking Models

• Layer communication

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Networking Models

• OSI Model
• To eliminate the problem of network
  incompatibility, ISO researched networking model
  such as
• DECnet
• SNA
• TCP/IP
• The OSI reference model released in 1984
• Provided vendors with a set of standards
• Become the primary model for network
  communications

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Networking Models

• OSI Model
• Dividing the network into 7 layers provides the
  following advantages
• It breaks network communication into smaller,
  more manageable parts.
• It standardizes network components to allow
  multiple vendor development and support.
• It allows different types of network hardware and
  software to communicate with each other.
• It prevents changes in one layer from affecting
  other layers.
• It divides network communication into smaller
  parts to make learning it easier to understand.

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Networking Models

• OSI Model Physical

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Networking Models

• OSI Model Data Link

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Networking Models

• OSI Model Network

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Networking Models

• OSI Model Transport

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Networking Models

• OSI Model Session

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Networking Models

• OSI Model Presentation

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Networking Models

• OSI Model Application

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Networking Models

• Peer-to-Peer communication
• Protocol at each layer exchange information,
  called protocol data units (PDUs)
• Each layer of OSI at source must communicate with
  its peer layer at the destination by exchanging
  layer-specific PDU
• The lower layer uses encapsulation to put PDU
  from upper into its data field then add its
  layer-specific information (headers, trailers)

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Networking Models

• Peer-to-Peer communication

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Networking Models

• TCP/IP Model
• Technical standard of the internet
• TCP/IP was developed as an open standard
• The layers in TCP/IP do not correspond exactly
  with OSI
• TCP/IP has 4 layers
• Application OSI session application
• Transport QoS, flow control, error correction
• Internet Best path determination and packet
  switching
• Network access both physical and logical
  required to make a physical link

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Networking Models

• Comparing TCP/IP with OSI

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Networking Models

• Common TCP/IP Protocol

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Networking Models

• TCP/IP Protocol and Ethernet

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Networking Models

• Detailed Encapsulation Process
• If hostA wants to send data to hostB, the data
  must first be packaged through encapsulation
  process
• Wrap data with the necessary protocol information
  before network transit
• As data moves down through OSI layers, it
  receives headers, trailers, other information

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Networking Models

• Detailed Encapsulation Process