ccna on coursera

ccna on coursera.2 Telnet Telnet is used to remotely manage devices, sends passwords in clear text, easy to be eavesdropped Use SSHv2 instead of Telnet, and restrict the IP address of remotely managed clients with ACLs 73 Exploit weaknesses of various network services By default, network devices have many common services enabled, such as finger, which have their own weaknesses and can be used by hackers to launch attacks on the device Keep the necessary services and turn off unnecessary ones 204 MAC flooding attacks Flood the switch with data frames by sending frames with false source MAC addresses to fill the MAC address table Enable port security 75 DHCP Spoofing, Depletion Attack, and Man-in-the-Middle Attack Deplete the DHCP server's address pool by first impersonating a DHCPCUent to request an IP address, and then impersonate a DHCP server to assign an IP address and perform a man-in-the-middle attack Enable DHCP Snooping 106 VLAN hopping attack Encapsulating the VLAN tag of a data frame into another VLAN, leading to cross-VLAN access and attacks Disabling Trunk negotiation on an interface, setting the Native VLAN to a non-existent VLAN 87 Attacks between devices in the same VLAN Computers in the same VLAN are communicating, leading to threats to other computers once one host is compromised Enable port isolation or use PVLAN technology 138 STP Root Attack Change STP tree topology by sending higher priority BPDUs, which become STP root bridges Enable STP root protection 149 VTP attack Sending fake VTP information to overwrite normal VLAN information Configuring VTP authentication 13.386.Cisco Networking Lab CCNA Lab Guide (2nd Edition)20.1.2 Basic Switch Security Measures