ccna 7 cisco

ccna 7 cisco.A network attacker can manipulate the STP by spoofing the root bridge and changing the network topology, to launch an attack. An attacker can make its hosts behave as the root bridge, thus capturing all traffic within the direct switching domain.To perform an STP manipulation attack, the attacking host broadcasts STP configuration and topology change BPDUs to force a spanning tree recalculation. The BPDUs sent by the attacking host advertise a lower bridge priority in an attempt to be selected as the root bridge. If successful, the attacking host becomes the root bridge, and thus can see a large number of data frames that would otherwise be inaccessible.This attack can defeat all 3 security objectives, namely confidentiality, integrity, and availability. Mitigating the STP Manipulation Attacktechniques for the attack include enabling PortFast as well as root protection and BPDU protection.6.2.5 LAN Storms6.2.5.1 LAN Storm AttacksLayer 2 devices are also vulnerable to LAN storm attacks. LAN storms occur when packets are flooded within the LAN, which can generateThis generates a large amount of traffic and thus degrades network performance. Errors in the protocol stack, improper network configuration, or user-initiated DoS attacks can cause storms.Storms.Since the switch forwards broadcasts through all ports, during an attack, broadcast, multicast, and unicast frames will be flooded on all ports within the same VLAN.