Browse Prior Art Database

Method for Allowing More than 255 Dependent Logical Units Over a Single Physical Line

IP.com Disclosure Number: IPCOM000118225D
Original Publication Date: 1996-Nov-01
Included in the Prior Art Database: 2005-Apr-01
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Carey, T: AUTHOR [+4]

Abstract

This disclosure is driven by a requirement to have an infinite number of dependent local Logical Units (dependent LUs) over a single physical link of any type. Furthermore, the solution has to be transparent to the existing dependent LU code.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 61% of the total text.

Method for Allowing More than 255 Dependent Logical Units Over a
Single Physical Line

      This disclosure is driven by a requirement to have an infinite
number of dependent local Logical Units (dependent LUs) over a single
physical link of any type.  Furthermore, the solution has to be
transparent to the existing dependent LU code.

      Currently, the Systems Network Architecture (SNA) assigns an
Address Space (AS) to a Path Control (PC) during the creation of a
Transmission Group (TG or physical link).  The architected address
space range only allows for 255 dependent LUs and 1 Physical Unit
(PU).  In order to achieve the desired requirement, multiple physical
links were required.

      This disclosure combines the capabilities of the Dependent
Logical Unit Requester (DLUR) architecture with a virtual TG (link)
concept to provide greater than 255 dependent LUs over a single
physical link while being transparent to the dependent LU code
underneath.

      The DLUR architecture addresses the requirement of allowing an
infinite number of dependent LUs over a single physical link of any
type.  This is accomplished by establishing an LU 6.2 session pipe
(known as the CP-SVR pipe) between the requester and its Dependent
Logical Unit Server (DLUS).  The requester multiplexes the PUs and
associated LU sessions over the CP-SVR pipe which runs over a single
physical link of any type.

      DLUR is only a partial solution because it leaves 1 address
spa...