Networking

• What does topology refer to in networking?

  The structure of a network
• What are the two types of network topology?

  Physical and logical
• What does physical network topology refer to?

  The actual hardware of a network
• What are the two types of physical network topology?

  Star and bus
• How does a physical star network connect clients?

  Each client has its own direct connection to the hub
• What is the role of the central hub in a physical star network?

  To receive all packets and them to the correct recipients
• How can a server be added to a physical star network?

  Like clients are connected to the hub
• What are the advantages and disadvantages of a physical star network?

  Advantages:

  • Direct packet delivery to recipients
  • Easy to add/remove clients
  • No collisions on cables
  • Cable failure does not affect others

  
  

  Disadvantages:

  • Central hub failure stops communication
  • Expensive installation due to cable length
• How does a physical bus topology connect clients?

  Clients connect to a single cable called a backbone
• What device is placed at either end of the backbone in a physical bus topology?

  A terminator
• What is a key difference between physical star and bus topologies?

  Star uses a central hub, bus does not
• What are the advantages and disadvantages of a physical bus network?

  Advantages:

  • No central hub reduces failure risk
  • Inexpensive installation

  
  

  Disadvantages:

  • Shared backbone allows packet visibility
  • Backbone failure makes the network unusable
  • Risk of collisions
• What does logical network topology refer to?

  The flow of data packets within a network
• How does a logical bus network deliver packets?

  To all clients on the network
• How does a logical star network deliver packets?

  Only to their recipient
• Can a physical star network behave as a logical bus?

  Yes, by running a bus protocol
• What does CSMA/CA stand for?

  Carrier Sense Multiple Access with Collision Avoidance
• What is the purpose of CSMA/CA?

  To avoid data collisions in wireless networks
• What does a device do when it is ready to transmit using CSMA/CA?

  It listens to the communication channel
• What happens if the channel is busy in CSMA/CA?

  The device waits for a random time
• What is an exponential backoff algorithm used for in CSMA/CA?

  To increase wait time after each check
• What problem does CSMA/CA not overcome?

  Hidden nodes
• What protocol is used to address hidden nodes in CSMA/CA?

  Request to send/clear to send (RTS/CTS)
• What does the transmitting device do after checking the channel in RTS/CTS?

  It sends a "request to send" message

  
• What does the server respond with if it is idle in RTS/CTS?

  A "clear to send" message
• What happens if no "clear to send" message is received?

  The device must wait before retrying
• What do wireless networks allow clients to do?

  Communicate without physical connections
• What is required for wireless networks to function?

  A wireless access point
• What does WiFi refer to?

  A wireless local area network
• What is the purpose of WiFi?

  Devices connect seamlessly worldwide
• How is data secured in wireless networks?

  By encrypting transmitted data using WPA/WPA2
• What does WPA stand for?

  WiFi Protected Access
• What is one method to secure a wireless network?

  Disabling SSID broadcast
• What does disabling SSID broadcast do?

  Stops the network from being displayed
• What is a MAC address?

  A unique identifier for devices
• How can MAC address filtering secure a network?

  By allowing or blocking specific devices
• What is a host in networking?

  A device that provides services
• What is a client-server network?

  One or more servers provide services to clients
• How are servers typically connected in a client-server network?

  Like clients, but are more powerful
• What services do servers provide in a client-server network?

  File storage, email management, print queues