H
- half duplex
The capacity to transfer data in only one direction at a time between a sending unit and receiving unit. See also full duplex.
- hardware address
A Data Link layer address assigned to every NIC at the MAC sublayer. The address is in the format xx:xx:xx:xx:xx:xx. Each xx is a two-digit hexadecimal number. See also Media Access Control (MAC), Network Interface Card (NIC).
- hardware loopback
A small plug used in a NIC that connects the transmission pins directly to the receiving pins, allowing diagnostic software to test whether a NIC can successfully transmit and receive. See also Network Interface Card (NIC).
- heartbeat
The data transmission between two servers in a cluster to detect when one fails. When the standby server detects ...
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