The HIPPI specification defines the mechanical, electrical and signalling protocol for a high performance simplex interface [data transmits in one direction only]. An additional HIPPI interface is required to transmit data in a full-duplex mode.

Parallel HIPPI operates bi-directionally (point to point) at 100 MBps [HIPPI-800] or with a throughput of 200 MBps [HIPPI-1600], up to 25 meters, using copper cabling [wire]. Serial HIPPI will run at 100 MBps [HIPPI-800 Serial], or 200 MBps [HIPPI-1600 Serial] using coaxial cable for distances up to 25 meter, and fiber optic cabling for distances up to 1K meter (Multi Mode) or 10K meters (Single Mode) HIPPI-6400 will run at 1.6Gbps [1.2 Gbaud rate]. The term HIPPI-800 means 800M bits per sec or 100M Bytes per sec, HIPPI-1600 refers to 1600 Bits per sec or 200M Bytes per sec. The HIPPI specification defines the physical layer and is used with LAN [Local Area Networks]. The data bus consists of either 32 bit data lines [D00 to D31] or 64 bit lines [D00 to D63].

Parallel HIPPI (HIPPI-PH) [PH is Physical] uses two 100 pin shielded twisted pair (STP) cables [50 twisted pairs, 28AWG wire], using differential ECL [copper wire interface]. Of course by definition all Emitter Coupled Logic [ECL] devices require Trace Termination. The Drain wire is also 28AWG, and the Braid shield wire is 36AWG. The HIPPI cables are grounded at both ends via the cable shield and connector shell bond. The pinout is defined in the HIPPI-PH Specification.
HIPPI-6400 is also termed Super-HIPPI, and may also be produced under the commercial name of Gigabyte System Network 'GSN'.

A HIPPI-PH channel transmits data in one direction [simplex interface], two channels are required for full-duplex operation. The HIPPI interface is a point-to-point bus that does not support multi-drop operation. Data runs in bursts, each burst contains between 1 and 256 words.