Please enable JavaScript.

Coggle requires JavaScript to display documents.

INTRODUCTION TO NETWORKS - Coggle Diagram

- - - - Transmission medium
      - Receiver(Signal)
      - Transmitter(Signal)
      - Message Destination(Message)
      - Message source(message)
    - - 2.Receiver(Set of rule)
      - 3.Medium(It were use between Transmitter and receiver)
      - 1.Transmitter(Set of rule)
      - 4.Message
      - 5.Protocol(Agreement between the communicating devices
    - - Protocols for successful human communication are:
        
        2.Agreed-upon medium or channel(face to face,telephone,letter,photographer)
        
        3.Appropriate communication mode(spoken,written,ilustrated,interactive or one way.
        
        1.Identification of sender and receiver
        
        4.Common language
        
        5.Grammar and sentence structure
        
        6.Speed and timing of delivery
      - Network Protocols
        
        Define a common format and set of rules for exchanging messages between devices.
        
        Common networking protocols are Hypertext Transfer Protocol (HTTP),Transmission Control Protocol(TCP) and Internet Protocol(IP)
      - PROTOCOL SUITE:
        
        Content layer
        
        Phycisal layer
        
        Rules layer
    - - Sender:Devices that use to sends the data message.For example:Computer,PC,Workstation,Telephone and etc
      - Receiver:Devices that receives the data messages.For example:computer,workstation,telephone handset and etc.
      - Message:Infomation to be communicated with each other.Infomation include in message such as text,pictures,audio,video and etc
      - Transmission Medium:Physical path by which a message travels from the sender to receiver .For example:Twisted pair wire,coaxial cable,radio waves and etc.
      - Protocol:Set of rules that governs the data messages.It represents an agreement between the communicating devices.Eithout the protocol,two devices may be connected but not communicating.
    - - Protocols are necessary for effective communication included:An identified sender and receiver,common language,speed and timing delivery,confirmation or acknowledgment requirements.
        
        TYPE OF PROTOCOLS:
        
        Message Size
        
        Human break long messages into smaller parts or sentences.
        
        Message Encoding:
        
        Encoding between hosts must be in appropriate format for the medium
        
        Message formatting and encapsulation
        
        Format for letters and addressing letters were required for proper delivery.
        
        Message timing
        
        1.Access Method
        
        2.Flow Control
        
        3.Respond Timeout
        
        Message Delivery Option
        
        2.Multicast Message(One to many delivery)
        
        3.Broadcast Message(One to all delivery)
        
        1.Unicast Message(One to one delivery)
    - - 2.Destination(Receiver):The destination receives the message and interprets it.
      - 3.Channel(Media)::Provides the pathway over which the message can travel from source to destination.
      - 1.Source(Sender):Message sources are people or electronic devices that need to communicate a message to other individuals or devices.
- - - - management dialog transfer protocol
    - - encapsulate the TCP segment into data packet ,assign an address ,and then pass it to the host
    - - application protocol that controls how web server and web client interact
    - - allows communication through data links and data transmission on network media
  - - - Application -
        
        PURPOSE- interfaces with applications
        
        Presentation -
        
        PURPOSE- data traslation & prep for network
        
        Session -
        
        PURPOSE- estab.&maintian comm link
        
        Transport -
        
        PURPOSE- breaks down mssg to send
        
        Network -
        
        PURPOSE- adds logical address info
        
        Data Link -
        
        PURPOSE- adds physcal addressing
        
        Physical -
        
        PURPOSE- converts to signal and sends
    - - The benefits of using a layered model include:
        
        ◦ Assisting in protocol design since protocols at each layer have defined functions.
        
        ◦ Fostering competition because products from different vendors can work together.
        
        ◦ Preventing technology changes in one layer from affecting other layers.
        
        ◦ Providing a common language to describe networking functions and capabilities.
    - - Application - contains protocols used for process-toprocess communications.
      - Presentation - provides for common representation of the data.
      - Session - provides services to the presentation layer to organize its dialogue and to manage data exchange.
      - Transport - defines services to segment, transfer, and reassemble the data.
      - Network - provides services to exchange the individual pieces of data over the network between identified end devices.
      - Data Link - provides methods for exchanging data frames between devices over a common media.
      - Physical - describes the mechanical, electrical, functional, and procedural means to transmit bits across physical connections.Reference
    - - application
        
        represents data to the user ,plus encoding and dialog control
      - transport
        
        supports communication between diverse devices across diverse networks
      - internet
        
        determines the best path through the network
      - network access
        
        controls the hardware devices and media that up the network
    - - Similarities
        
        Protocol standard
        
        combines the presentation and session layer issues into its application layer
        
        combines the OSI data link and physical layers into the network access layer
        
        a simpler model
      - Differences
        
        share similar architecture.
        
        share a common application layer
        
        Both models have comparable transport and network layers.
        
        Knowledge of both models is required by networking professionals.
  - - - When sending data from the network Server to client encapsulation program
        
        The web server prepares the Hypertext Markup Language (HTML) page. The HTTP application layer protocol sends the data to the transport layer.
        
        The transport layer breaks the data into segments and identifies each.
        
        Next the IP source and destination addresses are added, creating an IP Packet.
        
        The Ethernet information is then added creating the Ethernet Frame, or data link frame.
    - - Then the IP header
        
        Then the Transport layer header
        
        First the Ethernet header is removed
        
        Finally the HTTP information is processed and sent to the client’s web browser
- - - - Small Home Network
      - Small Office / Home Office Networks
      - Medium To Large Networks
      - World Wide Networks
    - - Common Types
        
        Local Area Network(LAN
        
        Wide Area Network(WAN)
      - Other Types
        
        Metropolitan Area Network (MAN)
        
        Wirelesss LAN (WLAN)
        
        Storage Area Network (SAN)
        
        Personel Area Network (PAN)
    - - The Internet
        
        The Internet is connecting a computer to any other computer anywhere in the world via dedicated routers and servers.
        
        When two computer are connected over the internet, they can send and receive all kind of information such as text, graphics, voice, video, and computer programs
      - Intranet
        
        An intranet is a computer network for sharing information, collaboration tools, operating systems, and other computing services within and organization, usually to the exclusion of access by outsiders
        
        Shared content accessed by member within a single organization
      - Extranet
        
        An Extranet is a controlled private network that allows access to partners, vendors and suppliers or an authorized set of customers Normally to a subset of the information accessible from an organization's intrane
        
        Sared content accessed by groups through cross-enterprice boundaries
  - - - A fault-tolerant network is one that limits the effect of a failure, so that the fewest number of devices affected by it
      - It is also build in a way that enables quick recovery when such failure occurs.
      - Fault-tolerant network depend on multiple path between the source and destination of a message. If one path fails, the messages can be instantly sent over a different link
      - Having multiple path to a destination is know as redundancy.
    - - A scalable network can expand quickly to support new users and applications without affecting the performance of the service being delivered to existing users
    - - Quality of service is also an ever-increasing requirement of networks today.
      - New applications available to users over internetwork, such as voice and live video transmission.
    - - securing a network infrastructure includes physically securing devices that provide network connectivity, and preventing unauthorized access to the management software that resides on those devices
- - - - NETWORK
        
        A network can be as small as two computers connected by a cable in a home office or as large as several thousand computers connected across the world via a combination of cable , phone lines, and cellular links.
        
        Example of actions that can be done using a Network
        
        Learn
        
        Communicate
        
        Work
        
        Play
        
        They might communicate through copper wires, fiber optic cable, or radio waves as transmission media.
        
        Advantages of Computer Network
        
        • Networks enable multiple users to share resources (devices and
        
        data)
        
        • Saves money.
        
        • Saves time.
        
        • Network allow you to manage, or administer, resources on
        
        multiple computers from a central location.
        
        Disadvantage of Computer Network
        
        Network Hardware, Software and Setup Costs
        
        2 . Hardware and Software Management and Administration Costs
        
        Undesirable Sharing
        
        4 . Illegal or Undesirable Behaviour
        
        5 . Data Security Concerns
        
        Client/Server Network Elements
        
        . 1. Client
        
        • A computer on the network that requests resources or services from another computer on a network.
        • In some cases, a client could also act as a server. The term client may also refer to the human user of a client workstation or to client software installed on the workstation.
        
        2 . Server
        
        • A computer on the network that manages shared resources.
        • Servers usually have more processing power, memory, and hard disk space than clients. Server run network operating software that can manage not only data, but also users, groups, security, and applications on the network.
        
        3 . Workstation
        
        • A personal computer (such as a desktop or laptop), which may or may not be connected to a network; most clients are workstation computers.
        
        4 . Network Interface Card (NIC)
        
        • The device inside a computer that connects a computer to the network media
        • Thus allowing it to communicate with other computers
        
        5 . Network Operating System (NOS )
        
        • The device inside a computer that connects a computer to the network media
        • Thus allowing it to communicate with other computers
        
        6 . Host
        
        • A computer that enables resource sharing by other computers
        on the same network.
        
        Node
        
        • A client, server, or other device that can communicate over a network and that is identified by a unique number, known as its network address.
        
        Connectivity Device
        
        • A specialized device that allows multiple networks or multiple parts of one network to connect and exchange data
        
        Backbone
        
        • The part of a network to which segments and significant shared devices (such as routers, switches, and servers) connect.
        • A backbone is sometimes referred to as “a network of networks” because of its role in interconnecting smaller parts of a LAN or WAN.
        
        Segment
        
        • A part of a network. Usually, a segment is composed of a group of nodes that use the same communications channel for all their traffic.
        
        Topology
        
        • The physical layout of a computer network . Topologies vary according to the needs of the organization and available hardware and expertise.
        • Networks can be arranged in a ring, bus , or star formation, and the star formation is the most common.
        • Hybrid combinations of these patterns are also possible
        
        Protocol
        
        • A format for communication between networked devices.
        • For example, some protocols ensure that data are transferred in sequence and without error from one node on the network to another.
        
        Transmission Media
        
        • The means through which data are transmitted and received • Transmission media may be physical, such as wire or cable, or atmospheric (wireless), such as radio waves.
        
        Fundamentals of Network Models
        
        Peer to Peer Networks (P2P)
        
        Client/Server Networks
        
        • Another way of designing a network is to use a central computer, known as a server; to facilitate communication and resource sharing between other computers on the network, which are known as clients.
        • A network that uses a server to enable clients to share data, data storage space, and devices is known as a client/server network.
        • A client/server architecture is sometimes used to refer to the design of a network in which clients rely on servers for resource sharing and processing