In general terms, a Host Bus Adapter (HBA) is any adapter that allows a computer bus to attach to another bus or channel. Today, the term is most often used to refer to a Fibre Channel interface card. However, the term has, in the past, referred to other bus interconnects, including SCSI and ESCON. Recently, the advent of iSCSI has brought about Ethernet HBAs, some including TCP Offload Engines.
Fibre Channel HBAs are available for all major open systems computers and busses, including PCI and SBUS. Each HBA has a unique World Wide Name (WWN), which is similar to an EthernetMAC address in that it uses an OUI assigned by the IEEE. However, WWNs are longer (16 bytes).
The hostadapter bridges the physical and logical chasm that separates the SCSI bus from the host computer's internal bus.
Modern hostadapters contain all the electronics and firmware required to execute SCSI transactions, and often include a BIOS that not only allows the host system to boot from a SCSI device, but also facilitates configuration of the hostadapter.
Each HBA has a unique World Wide Name (WWN), which is similar to an Ethernet MAC address in that it uses an OUI assigned by the IEEE.
PCI busadapters transfer 32 or 64 bits of data at a clock speed of 33 MHz and support three to five critical peripherals, which integrate either directly onto the motherboard or via expansion cards.
Busadapters also differ according to the number of terminating connections or the range of acceptable ports or slots that can be added to the system.
PCMCIA busadapters are cards that plug into a 68-pin host socket connected either to the motherboard or to an expansion.
Feeds |
Contact