JetDirect

HP Jetdirect is the name of a technology sold by Hewlett-Packard that allows computer printers to be directly attached to a Local Area Network. The "Jetdirect" designation covers a range of models from the external 1 and 3 port parallel print servers known as the 300x and 500x, to the internal EIO print servers for use with HP printers. The Jetdirect series also includes wireless print server (Bluetooth, 802.11b and g) models, as well as gigabit Ethernet and IPv6-compliant internal cards.

HP Jetdirect was first introduced in March 1991 (code named QuickSilver) with the LaserJet IIIsi network printer (code named Eli). Jetdirect is based on HP's MIO (Modular Input/Output) interface, which was designed from the ground up with the IIIsi to create a mainstream full function high performance networked printer. The initial MIO interface card had Ethernet and Token Ring physical layer variants and used various over an AUI/BNC connection. Initially, a printer needed a separate card for each protocol, such as TCP/IP, IPX/SPX, AppleTalk, or DLC/LLC. The following year the team applied the technology to the legacy accessory slot on the LaserJetIIs and IIIs XIO (Extended Input/Output). MIO type Jetdirect cards were also used for network connectivity on some HP/Agilent laboratory equipment such as the 6890A and 6890 Plus series of gas chromatographs. These included unusual network connection types such as HPs I-Net which was used as an interconnect between various pieces of hardware that controlled the 58xx and 68xx series gas chromatographs. Not until 1994 would MIO interface cards be released that could support more than one protocol per card.

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