Browse Prior Art Database

Description of the Service Interface of the IBM Wireless LAN Card

IP.com Disclosure Number: IPCOM000116006D
Original Publication Date: 1995-Jul-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 4 page(s) / 82K

Publishing Venue

IBM

Related People

Bauchot, F: AUTHOR [+3]

Abstract

Disclosed is an interface mechanism between two communicating entities such as an I/O adapter card and its Device Driver (DD) which contains some key features addressing the following characteristics: discrimination between multi-type data frames, point-to-multipoint topology, congestion control, flow negotiation, data integrity checking. The following description assumes a DD-to-I/O card interface, but can be generalized to other types of interfaces.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Description of the Service Interface of the IBM Wireless LAN Card

      Disclosed is an interface mechanism between two communicating
entities such as an I/O adapter card and its Device Driver (DD) which
contains some key features addressing the following characteristics:
discrimination between multi-type data frames, point-to-multipoint
topology, congestion control, flow negotiation, data integrity
checking.  The following description assumes a DD-to-I/O card
interface, but can be generalized to other types of interfaces.

      The interface is based on two communication mechanisms:
  1.  A mail box mechanism that allows
      a.  The DD to send 1 Byte to the adapter and interrupt the
           microcode,
      b.  the Microcode to send 1 Byte to the DD and interrupt the
           microcode.
      This Mechanism is used for commands/control of the interface.
  2.  A First In/First Out (FIFO) mechanism that used to send data
both
       ways

      The working principle of this interface is the following:  When
the DD sends a frame to the adapter, it first signals it with a mail
box, then sends a header in the FIFO that indicates to the adapter
the type (Data,Control,network management) of the frame to be sent
(e.g., 1 byte), its size (e.g., 2 bytes), and the destination address
(e.g., 6 bytes), and then the actual frame to the FIFO.  When the
Adapter sends a frame to the DD, it first signals it with a mail box,
then...