Digital Ethernet Local Network Interconnect

A Digital Ethernet Local Network Interconnect (DELNI)

The Digital Ethernet Local Network Interconnect (DELNI) was an Ethernet hub with nine ports and AUI connectors, made by Digital Equipment Corporation (DEC). Ports one to eight had male connectors and are normally used to attach computer interfaces directly. Port number nine (marked by a square instead of a number) had a female connector and was used to attach a media access unit (MAU), for example a DESTA with a thinwire connector or the H4000 for thickwire Ethernet.

The ninth port could also be used as an input from another DELNI. Cascading was allowed for a maximum of two steps. If the ninth port was used for that purpose, then the switch next to it was set to the upper position (marked by an empty square). This switch was in the lower position (crossed square) when port nine is attached to a computer system.^{[1] [2]}

The DELNI had its own power supply switchable between 120VAC and 240VAC. It had a standard 19" wide rackmount housing and occupied 1.5 rack units. The DELNI was also available as a desktop (or better floor-stand) unit with cosmetic plastic covers.

The DELNI was produced from 1983 until it was replaced by the so-called "Replacement DELNI" in 1994. This replacement DELNI had exactly the same functions but was produced with more modern components and a more stylish cover.

PAIX, one of the earliest Internet exchange points, used a DELNI as its interconnection infrastructure.^[3]

References

1. DEC DELNI Installation and Owners Manual PN: EK-DELNI-IN-002
2. "DEC Replacement DELNI Installation and Operating Information PN: EK-DELNX-IN.A01" (PDF). Feb 1992. Retrieved 2010-12-26.
3. "NANOG post by Stephen Stuart: "Re: IXP"". April 18, 2009. Retrieved 2009-11-18.