Browse Prior Art Database

Optical Switch Response Buffer

IP.com Disclosure Number: IPCOM000120279D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 2 page(s) / 53K

Publishing Venue

IBM

Related People

Peterson, MJ: AUTHOR [+2]

Abstract

Disclosed is a method of sending a message (frame) on a serial channel. This method is implemented in a port adapter device as a part of a fiber-optic switching system. (Image Omitted)

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 86% of the total text.

Optical Switch Response Buffer

      Disclosed is a method of sending a message (frame) on a
serial channel. This method is implemented in a port adapter device
as a part of a fiber-optic switching system.

                            (Image Omitted)

      The Port Adapter (PA) in the fiber-optic switch must be able to
respond with BUSY frames or several kinds of REJECT frames to
incoming request frames.  The response buffer in the PA provides this
function.  These responses may have header information associated
with them, or they may only contain the data portion of the frame and
require the hardware to provide the header information.  This allows
the processor to load the response buffer with a DATA FRAME if
desired and have the hardware send the header information.

      The PA response buffer is used to hold a frame generated by the
CP before it is transmitted at link speeds and for
controller-initiated internal testing of the PAs and matrix switch.
The response buffer will be read out by PA, but not written by it.
The PA will read this buffer upon receiving a CP Bus Trigger command
telling it to send a frame.  The layout of the response buffer is
shown in the figure.

      When a Send Frame command is received from the switch's control
processor, the PA will start transmitting from location X'1' of the
buffer and send until location X'F'. The CP must ensure that the PA
generates the correct delimiter (by setting bits in...