IPv4

  • The network layer

    • Provides services for fragments of data exchanged over the network between each terminal device
    • The basic process
      • addressing
      • encapsulation
      • routing
      • decapsulation
    • agreement
      • Internet Protocol Version 4 (IPv4)
      • Internet Protocol Version 6 (IPv6)
      • AppleTalk
      • Novell Internet Packet Switching Protocol (IPX)

  • Network layer protocol instance

    • IPv4 encapsulates transport layer data segments or packets to be sent across the network to the destination host. In any case, the data part of the packet, the transport layer of the encapsulationPDUWill remain unchanged throughout the network layer

Split the host into groups

  • Network Division Basis
    • The geographical position
    • use
    • The ownership of
  • Why divide hosts into networks?
    • performance
    • security
    • Address management
  • How to divide the network?
    • Hierarchical addressing

routing

  • IP packets – Send data end-to-end
  • Gateway – The exit to the network
  • Routing – The path to the network
  • Next hop – the next destination of the packet

  • Packet forwarding – Sending packets to their destination host
    • Forward to the destination host
      • A directly connected network
    • Forward to the next-hop router
      • There is a match entry
      • There is no match entry but a default route exists
    • discarded
      • There is no match and no default route

Routing protocol

Static route: Finish the configuration on the router

Dynamic routing: Routers dynamically share the set of rules by which their routing protocols are based

Common dynamic routing protocols include:

  • Routing Information Protocol (RIP)
  • Enhanced Internal Gateway Routing Protocol (EIGRP)
  • Developing Shortest Path First (OSPF)