NETWORK TOPOLOGIES - jude-lindale/Wiki GitHub Wiki

  • Local area networks are defined in terms of the protocol and the topology used for accessing the network.

  • The Protocol: A set of rules established for users to exchange information.

  • The topology: The network architecture of a network.

    • The most common architectures for LANs are the ring, bus, and star. 01fig01

  • Token Ring Topology: A network topology configured in a logical ring that complements the token-passing protocol 01fig02

  • Token Passing: A technique in which an electrical token circulates a network, and control of the token enables the user to gain access to the network

  • IEEE: Institute of Electrical and Electronics Engineers, one of the major standards-setting bodies for technological development

  • Deterministic: A type of network in which access to the network is provided at fixed time intervals

Disadvantages to a Token Ring system

  1. if an error changes the token pattern, it can cause the token to stop circulating
  2. The ring networks rely on each system to relay data to the next user
    • A failed station can cause data traffic to cease
  3. The Token Ring path must be temporarily broken if a computer or any device connected to the network is to be removed or added to the network

  • A fix to this is to attach all the computers to a central Token Ring hub -Token Ring Hub: A hub that manages the passing of the token in a Token Ring network

  • Bus Topology is a system in which the computers share the media (coaxial cable) for data transmission 01fig03 -Star Topology is the most common networking topology in today's LANs, where all networking devices connect to a central switch or hub

    • The Hub is a device that broadcasts the data it receives to all devices connected to its ports (it provides the network connection)
      • A Multiport Repeater is just another name for a hub
      • Broadcast is the transmission of data by a hub to all devices connected to the hubs ports
    • To minimize unnecessary data traffic and isolate sections of the network, a switch can be used at the center of a star network.
      • A _Switch _ is a device that forwards a frame it receives directly out the port associated with its destination address 01fig04

  • Mesh Topology is a topology in which all networking devices are directly connected

    • This provides full redundancy in the network data paths but at an increased cost 01fig05