Computer bus:
to solve the problem connected to different devices, different devices connected to the system bus
memory:
CPU> Cache> main memory (RAM)> secondary memory (hard disk)
computer network
Application layer (http, ftp ...) -> Transport Layer (tcp / udp) -> network layer (IP) -> Data Link Layer -> physical layer
data link layer
Encapsulated in a frame (frame header, data, tail frames), transparent transmission, error detection
maximum transmission unit: the MTU, typically 1500 bytes
Ethernet protocol:
Encapsulation: [type of frame the source address in the CRC data]
Network layer
arp protocol:
Mapping Address Resolution Protocol ip and mac address
to view the arp cache: arp -a
ICMP protocols:
Internet Message Protocol
Transport Layer
Interprocess communication with the process, a different port editing process
udp:
Encapsulation: [udp application layer header data]
User Datagram Protocol, not merged, not split application layer data
connectionless unreliable, reported for packet transmission, no congestion control, header overhead is small (source port, destination port, udp data, checksum)
tcp:
encapsulation: [tcp header data tcp]
transmission control protocol
connection-oriented, reliable, full duplex work, the byte-stream-oriented, user data will merge, split,