To be added to improve
Request course Web page
Application layer
Message master
Transport Layer
Segment,
Network layer
Datagrams, routers, IP address
Link layer
Ethernet frame switch, MAC address
Step 1) to 4), involves three machines are portable, Ethernet switches, routers
Portable device: generates the DHCP request packet, encapsulates the packet into the segment, the segment encapsulated datagram, the datagram is encapsulated into an Ethernet frame, the broadcast Ethernet frame
Ethernet Switches: receiving portable pass over Ethernet frames, the broadcast Ethernet frame
Router: receiving an Ethernet frame from the Ethernet switch, extracts packet data from the Ethernet frames, extracting the data packets from the segment extracted from the DHCP request packet segment
Note: DHCP server running on the router
Host: an application layer, transport layer, network layer, link layer
Switch: link layer
Router: a link layer, network layer, transport layer, application layer
LAN address, physical address and MAC address is one thing, they are link-layer address
Not host or router has a link-layer address, but their adapters (i.e., network interface) link-layer address having
DNS to resolve host names to IP addresses, DNS host to resolve host names anywhere on the Internet
ARP resolves the IP address for the MAC address, ARP interface only resolve the IP address for hosts and routers in the same subnet
IP 5.7.1 get their own IP, default gateway router's IP, DNS server, network mask
5.7.2 obtained gateway router MAC
5.7.3 obtain an IP www.google.com