Browse Prior Art Database

Optimized Splitting of an Integrated Services Digital Network Layer 1 Interface

IP.com Disclosure Number: IPCOM000122285D
Original Publication Date: 1991-Nov-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 2 page(s) / 45K

Publishing Venue

IBM

Related People

Luechtefeld, RA: AUTHOR [+4]

Abstract

ISDN (Integrated Services Digital Network) is an evolving standard for data transmission. There is no common set of safety or power sensing requirements for countries implementing this standard. A method for splitting an ISDN Layer 1 interface to allow flexibility in meeting safety and power sensing requirements is disclosed.

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This is the abbreviated version, containing approximately 98% of the total text.

Optimized Splitting of an Integrated Services Digital Network Layer
1 Interface

      ISDN (Integrated Services Digital Network) is an evolving
standard for data transmission.  There is no common set of safety or
power sensing requirements for countries implementing this standard.
A method for splitting an ISDN Layer 1 interface to allow flexibility
in meeting safety and power sensing requirements is disclosed.

      The Layer 1 front end circuitry is split into two parts.
Circuitry which is unlikely to change is placed on a main logic card.
Circuitry which is unique to a certain set of requirements, or likely
to change as the standard evolves, is placed on a network interface
adapter card. This second card is packaged "offboard" so that it may
be easily removed and replaced.

      All safety requirements (isolation, fusing, etc.) and
network-side power source-sensing components are placed on the
network interface adapter card.  Several network interface adapter
cards may be developed to meet the requirements of different
networks, while the main logic card can remain unchanged.  This is
illustrated by the figure.

      Components on the main logic card include drivers and
receivers, relays, secondary surge suppression, and secondary-side
power source sensing components.  Components on the network interface
adapter card include transformers, fuses, surge suppressors, ferrite
beads (for electro-magnetic interference reduction), and network-side
power s...