2. OBJECTIVE: o Describe various network topologies o Discuss the role of network devices o Understand Network Configuration Factors to deploy a new network

3. 1.0 NETWORK TOPOLOGIES  Physical layout of computers, cables and other components on the network  Also referred as:  Physical Layout  Design  Diagram  Map 1.1 Purpose of Network Topology  How computers communicate on the network  Different topology – Different communication method 1.2 Types of Network Topologies  Bus  Star  Ring

4. 1.2.1 Bus  Terminals are connected in a row along a single cable  Single cable is also known as Trunk, Backbone or Segment 1.2.1.a How it works?  Sending host sends the data to all computers in network  Only that node accepts the data whose address matches the destination code  Only one computer can send data at one time  Network performance affects as number of nodes increases  If one computer fails it does not affect rest of the network  Terminators are installed at each end to absorb free signals (signal bouncing)  Network becomes down if one end is empty or cable is physically cut

6. 1.2.2 Star  Terminals are connected by a cable segment to a central device  Central Device can be a HUB or Switch 1.2.2.a How it works?  Sending host sends the data to central device  Central Device sends the data to receiving host  If central device fails, the entire network becomes down  If one computer or one cable fails, it does not affect rest of the computers

8. 1.2.3 Ring  Terminals are connected on a single circle of cable  No terminated ends 1.2.3.a How it works ?  Signals travel in a loop in one direction and pass through each computer  Each computer acts like a repeater unlike passive bus topology  Failure of one computer can impact the entire network  Ring topology use TOKEN PASS technology

10. 2.0 NETWORK DEVICES PURPOSE OF NETWORK DEVICES:  Regulate the speed at which network information travels  Manage flow of traffic, opening, closing and directing of traffic  Protect sensitive information

11. 2.1 Network Interfaces  Network Interface Card (NIC) is a device used to connect computers, printers and other peripherals to a network  Sending NIC --- Parallel into serial form  Receiving NIC --- Serial into Parallel form  Speed is measured in bps  Each NIC has a unique MAC address  Each NIC is assigned an IP Address by Network Administrator

12. 2.2 HUB  HUB stands for Hybrid Universal Bus  A small device gathers the signals from each individual device optionally amplifies, and sends the data to all other connected devices  All devices connected to a HUB share the bandwidth of network  More devices connected to a HUB, lower the network performance  12 or 24 ports available in standard HUB  Speed is measured in bps

13. 2.3 Switch  Switch works exactly in the same way as HUB except:  It does not broadcast  It does not interfere network bandwidth  8, 12, 24 Ports are usually available  Speed is measured in bps  Must be compatible with other network devices

14. 2.4 Routers  Routers connect two or more networks of different design  Find the best path (route) to transmit data  Routers can be programmed to define traffic rules  Expertise are required to configure routers

15. 2.5 Firewalls  A device (combination of hardware and software) that protects unauthorized access to a network Types of Firewalls  Packet Screening Firewalls  Proxy Servers  State full Inspection Proxies

16. 3.0 NETWORK CONFIGURATION FACTORS i.Choosing the Network Type / Utilization Peer to Peer Server Based Networking ii.Choosing the Network Topology / Performance Bus Star Ring iii.Choosing the Communication Media / Performance Physical Media Wireless Media Light Emitted Media iv.Future Considerations / Flexibility v.Cost vi.Maintenance