VMware NIC teaming is a way to group several network interface cards (NICs) to behave as one logical NIC.
Any physical NIC bonded to the NIC team will transmit packets, and packets coming in from a physical NIC to the appropriate logical NIC. The virtual machines assigned to a logical NIC are not aware of the physical NICs supporting the system.
Properly configured NIC teams allow guest virtual machines (VMs) in a VMware ESX environment to failover if one NIC or network switch fails. VMware NIC teaming also helps load balance network traffic. Bonding NICs can also improve fault tolerance by preventing a single point of failure for the physical NICs; this is sometimes called NIC redundancy.