Data link layer
function
link creation, maintenance, management
frame encapsulation, transmission, synchronization
error check
address
MAC address Media Access Control address structure 48-bit binary number 12 hexadecimal digits
frame encapsulation certain source MAC // MAC / / data // CRC
switch works learning / broadcast / forward / update
up local area network
1 install the software cisco cpt
2 deployment of switches and host
3 direct line connection, host and switch.
4 arranged for each IP host, ping each test
5 by show mac-address-table. Observation switch works.
6 Replace the interface to a host computer connected to the switch, the ping test again observe update the switch.
Network layer
Brief IP address classification
category A (1 ~ 126) Class B (128 ~ 191) C class (192 to 223) Class D (224 ~ 239) a multicast Class E (240 to 255) Research
Description of private IP addresses Category
Category A: 10.0.0.0 ~ 10.255.255.255
class B: 172.16.0.0 ~ 172.31.255.255
C class: 192.168.0.0 ~ 192.168.255.255
