Introduce some of the next attacks and solutions _ security settings

MAC addresses flooding
To make the switch's Mac table full by simulating a large number of source MAC addresses
can be solved by port security.

VLAN hopping
Access to other VLANs by changing the packet Vlan-id
Strictly set trunk allow which VLAN to pass, put the useless port into the common VLAN (i.e. vlan1)

Attacks between devices on a common VLAN
Devices that belong to the same VLAN can also attack each other.
Through the Pvlan to solve

DHCP starvation
An attacker sends countless DHCP requests, come on. The address in the DHCP server address pool is depleted
Using DHCP snooping to resolve

STP compromises
The attackers set their own bridge priority to be the biggest, so that they become bridge root.
Manually set bridge priority to 0 and set up a backup root to open root guard

Mac Spoofing/arp Spoofing
The attacker would change his MAC address to the MAC address of the target, so that he could receive data from the attacker.
Manually bind MAC addresses and interfaces, or ARP inspection

CDP manipulation
Because the CDP information is plaintext, an attacker can crawl its information
Turn CDP off on an interface that does not need to run CDP

SSH and Telnet attacks
Some attacks on SSH and Telnet
Using SSH v2, use Access-class for Telnet