Please enable JavaScript.

Coggle requires JavaScript to display documents.

Chapter 1 Explore The Network, OSI Model And TCP/IP Model Comparison,…

- - - - Undesirable Sharing
      - illegal or undesirable behaviour
      - Hardware and Software Management and Administration Costs
      - Data security concerns
      - Network Hardware, Software and Setup Costs
    - - Enable multiple users to share resources
      - Saves money
      - Saves time
      - Network allow you to manage, or administer, resources on multiple computers from a central location.
  - - - A computer on the network that manages shared resources.
    - - A personal computer, which may or may not be connected to a network; most clients are workstation computers.
    - - A computer on the network that requests resources or services from another computer on a network.
    - - The device inside a computer that connects a connects a computer to the network media.
    - - The software that runs on a server and enables the server to manage data, users, groups, security, applications, and other networking functions.
    - - A computer that enables resource sharing by other computers on the same network.
    - - 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.
    - - A specialized device that allows multiple networks or multiple parts of one network to connect and exchange data.
    - - Part of a network which segments and significant shared devices connection and sometimes as "a network of networks" when its role in interconnecting smaller parts of a LAN or WAN.
    - - A part of a network that composed of a group of nodes that use the same communications channel for all their traffic.
    - - The physical layout of a computer network.
    - - A formal for communication between networked devices.
    - - The means through which data are transmitted and received.
  - - - Advantages
        
        Less complexity
        
        Lower cost since network devices and dedicated servers may not be required
        
        Easy to set up
        
        Can be used for simple tasks such as transferring files and sharing printers
      - Disadvantages
        
        Not as secure
        
        Not scalable
        
        No centralized administration
        
        All devices may act as both clients and servers which can slow their performance
    - - 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.
      - A network that uses a server to enable clients to share data, data storage space, and devices is known as a client/server network.
      - 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.
  - - - Local Area Network(LAN)
      - Wide Area Network(WAN)
    - - Storage Area Network(SAN)
      - Wireless LAN(WLAN)
      - Personal Area Network(PAN)
      - Metropolitan Area Network(MAN)
    - - The Internet
        
        connection between two computers at anywhere via dedicated routers and servers to send and receive all kinds of information
        
        NETWORK OF NETWORK
      - Intranet
        
        Shared content accessed by members within a single organization
      - Extranet
        
        Shared content accessed by groups through cross-enterprise boundaries.
  - - - Limits the effect of a failure and enables quick recovery when such a failure occurs. Redundancy-depend on multiple paths between the source and destination of a message.
    - - QoS is an ever-increasing requirement. New applications available to users over internetworks.
    - - A scalable network can expand quickly to support new users and applications without affecting the performance of the service being delivered to existing users.
    - - Securing a network infrastructure provide network connectivity, and preventing unauthorized access to the management software that resides on those devices.
- - - - It is the information to be communicated. Popular forms of information include text, pictures, audio, video
    - - It is the device which sends the data messages. It can be a computer, workstation, telephone handset
    - - It is the device which receives the data messages.
    - - It is the physical path by which a message travels from sender to receiver. Some examples include twisted-pair wire, coaxial cable, radio waves and etc.
    - - It is a set of rules that governs the data communications. It represents an agreement between the communicating devices. Without a protocol, two devices may be connected but not communicating
  - - - Encoding between hosts must be in appropriate format for the medium. Messages are first converted into bits by the sending host.
    - - Unicast Message
        
        One-to-one delivery
      - Multicast Message
        
        One-to-many delivery
      - Broadcast Message
        
        One-to-all delivery
    - - An agreed format for letters and addressing letters which is required for proper delivery.
        Putting the letter into the addressed envelope is called encapsulation.
    - - Access Method
        
        Hosts on a network need to know when to begin sending messages and how to respond when collisions occur.
      - Flow Control
        
        Source and destination hosts use flow control to negotiate correct timing to avoid overwhelming the destination and ensure information is received.
      - Response Timeout
        
        Hosts on the network have rules that specify how long to wait for responses and what action to take if a response timeout occurs.
    - - Human break long messages into smaller parts or sentences.
      - Long messages must also be broken into smaller pieces to travel across a network.
        
        Each piece is sent in separate frame.
        
        Each frame has its own addressing information.
        
        A receiving host will reconstruct multiple frames into original message.
  - - - Message sources are people, or electronic devices, that need to communicate a message to other individuals or devices.
    - - The destination receives the message and interprets it.
    - - Provides the pathway over which the message can travel from source to destination.
  - - - The process by which networking devices share information about pathways with other networks
      - How and when error and system messages are passed between devices
      - How the messages is formatted or structured
      - The setup and termination of data transfer sessions
  - - - TCP transport protocol that manages the individual conversations.
      - IP encapsulates the TCP segments into packets, assigns addresses, and delivers to the destination host.
      - HTTP an application protocol that governs the way a web server and a web client interact.
      - Ethernet allows communication over a data link and the physical transmission of data on the network media.
  - - - The webserver prepares the Hypertext Markup Language (HTML) page. The HTTP application layer protocol sends the data to the transport layer.
      - The tansport 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.
      - This frame is delivered to the nearest router along the path towards the web client. Each router adds new data link information before forwarding the packet.
  - - - 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 make up the network.