TOPIC 1

• The term Network Topology defines the geographic arrangement of computer networking devices.
• The term Topology refers to the way in which the various nodes or computers of a network are linked together.
• It describes the actual layout of the computer network hardware. 


  topology
• Two or more devices connect to a link; two or more links form a topology.
• Topology determines the data paths that may be used between any pair of devices of the network.
• There’s no one-size-fits-all when it comes to network topology.
• What is perfect for one organization may be woefully inadequate in another.
• Key factors to pay attention to when choosing a network topology

  • Budget
  • Hardware Resources
  • Ease of Implementation
  • Size of Network
  • Reliability
  • Future Expansion
• Budget


  Never make technology procurement decisions based on price alone, but you can only cut your coat according to your cloth
• Affordable network topologies

  • Bus
  • Ring
• Expensive network topologies

  • Star
  • Mesh
  • Tree
  • Hybrid
• Hardware Resources


  Certain network topologies work best with certain hardware, and vice-versa
• Hardware limitations such as cable length


  Go for a topology that requires the least amount of cable for connecting nodes
• Topologies that perform well with limited cable length

  • Bus
  • Star
• Ease of Implementation


  If network implementation is left to novices or individuals without IT training, the ease of the topology should be a major factor
• Easy to implement topologies

  • Bus
  • Star
• Complex and difficult to implement topologies

  • Mesh
  • Tree
  • Hybrid
• Size of Network


  Some topologies are inadequate or expensive when applied to large networks
• Topology suitable for large networks

  • Tree
• Topology suitable for small networks

  • Bus
• Reliability


  When it comes to reliability, network topologies aren't created equal
• Reliable topologies

  • Mesh
  • Hybrid
• Less reliable topologies

  • Ring
  • Star
• Future Expansion


  Choose a topology that's easy to add new nodes to, without negatively affecting network performance or user experience
• what are the key factors when choosing a network topology?

  1. budget
  2. hardware resources
  3. ease of implementation
  4. size of network
  5. reliability
  6. future expansion
• Budget. 


  A rule of thumb is to never make technology procurement decisions based on price alone.
• There’s no denying though that you can only cut your coat according to your cloth. If a topology is unaffordable, it’s off the table no matter how perfectly suited it might be for your situation. 


  budget
• In any case, irrespective of what your preferred topology is, there’ll almost always be a lower priced alternative that’s nearly as effective. 


  budget
• On pricing matters, bus and ring topologies are quite cost effective while star, mesh, tree and hybrid topologies are expensive. 


  budget
• Hardware Resources 


  Certain network topologies work best with certain hardware. And vise-versa.
• So before you make a decision on the topology to adopt, perform an inventory of your current hardware. 


  hardware resources
• You may also already have the hardware needed to implement a certain type of topology. 


  hardware resources
• So as opposed to buying everything from scratch, such existing resources give you a head start. 


  hardware resources
• For instance, you may have hardware limitations such as the length of the network cable. In that case, you’d go for a topology that requires the least amount of cable for connecting nodes. Bus and star topologies perform pretty well in this regard.


  hardware resources
• Ease of Implementation 


  If you’ll contract a third party to install and/or maintain your network, then the complexity of the network topology you choose is perhaps a non-issue.
• A competent networking professional will have the education and experience needed to comprehend what each topology entails and implement it accordingly. 


  ease of implementation
• However, if you expect to leave network implementation in the hands of novices or individuals without the requisite IT training, then the ease of the topology should be a major factor in your choice.


  ease of implementation
• In this case, the bus and star topologies score pretty well. The mesh, tree and hybrid, on the other hand, are complex and difficult for a layman to install or understand.


  ease of implementation
• Size of Network 


  How many devices are going to be on your network? How geographically dispersed are they? How far from the ‘center’ is the furthest device? Some topologies are inadequate or expensive when applied to large networks.
• A topology that works perfectly for a 5-device network may prove a disaster when applied to a 10,000-device organization. 


  size of network