Fibre Channel Switch Relative Addressing for Identifier Persistence

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In Fibre Channel networks, when a run-time domain changes, the corresponding Fibre Channel identifiers become invalid, causing frustration for administrators and degrading network performance due to the need to manually configure identifiers and the loss of device connections.

Innovation Solution

Implementing a relative addressing scheme in Fibre Channel switches that assigns a relative domain field value to each device, using reserved domain field values (0 and 240-255) or regular domain values in a new VSAN, allowing Fibre Channel identifiers to remain valid even if the run-time domain changes, by not explicitly storing the domain field in the identifiers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If Fibre Channel identifiers store absolute domain values, then the identifiers are valid within a specific domain, but the identifiers become invalid when the run-time domain changes, requiring manual reconfiguration

Engineering Contradiction:
Improveidentifier validityVSAvoidmanual reconfiguration burden
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent changes the parameter representation from absolute domain values to relative domain values. Instead of storing the actual domain number (e.g., domain 10), the system stores an offset value (e.g., 0) that is added to a base domain value. This transformation allows identifiers to automatically adapt when domain values change, eliminating the need for manual reconfiguration while maintaining identifier validity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces dynamic adaptability to Fibre Channel identifiers by using relative addressing. The identifiers are no longer static with fixed absolute domain values, but dynamically adjust to domain changes through the relative offset mechanism. When the base domain changes, all identifiers automatically update their effective domain value without requiring manual intervention.

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If Fibre Channel identifiers are manually configured, then administrators have control over identifier assignment, but significant administrative time is required when domain changes occur

Engineering Contradiction:
Improveidentifier controlVSAvoidadministrative time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent implements preliminary action by pre-configuring relative offset values that are designed to be invariant to domain changes. The system anticipates future domain changes and structures the identifiers with relative addressing that automatically adapts, eliminating the need for administrative reconfiguration work when domains change.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent enables self-service by allowing Fibre Channel identifiers to automatically adjust themselves when domain values change. The relative addressing mechanism causes identifiers to self-update their effective domain value without requiring administrator intervention, thus eliminating administrative time expenditure while maintaining control through the initial relative offset configuration.

Inventive Principle:
Principle #25Self-service

3Reliability

If Fibre Channel identifiers are lost when domain changes, then the system maintains domain uniqueness, but network performance is degraded due to connection loss

Engineering Contradiction:
Improvedomain uniquenessVSAvoidnetwork performance
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent segments the domain identification into two parts: a base domain value and a relative offset value. This segmentation allows the system to maintain domain uniqueness through the base value while using the offset to preserve identifier continuity. When domain changes occur, the base value updates but the relative offsets remain valid, preventing identifier loss and maintaining network connections.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a relative offset as an intermediary between the base domain value and the final identifier. This intermediary layer decouples the identifier from direct dependence on the absolute domain value, allowing domain changes to occur without losing identifier validity. The relative offset mediates the relationship, enabling both domain uniqueness and identifier persistence.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Quantity of substance

If thousands of Fibre Channel identifiers are stored in persistent memory, then device connectivity is maintained, but reconfiguration requires deleting and reconfiguring all entries

Engineering Contradiction:
Improveidentifier storage capacityVSAvoidreconfiguration complexity
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The patent changes the storage parameter from absolute domain values to relative domain offsets. This parameter transformation allows all stored identifiers to automatically adapt to domain changes without requiring deletion or reconfiguration. The relative offset representation maintains storage capacity while dramatically simplifying reconfiguration complexity.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2633645B1Domain-independent persistent fibre channel identifiers
Publication Date: 2016.08.17 CISCO TECHNOLOGY INC
  • EP2633645B1 patent drawingFigure 1
  • EP2633645B1 patent drawingFigure 2
  • EP2633645B1 patent drawingFigure 3~4

AI summary

A Fibre Channel switch and related methods are provided for a relative addressing scheme for domain values used by the switch to avoid losing other portions of a Fibre Channel identifier if a particular run-time domain becomes invalid. At a Fibre Channel switch, data is stored that assigns a relative domain field value to a run-time domain in one of a plurality of virtual storage area networks. The relative domain field value used for a Fibre Channel identifier is determined for each of a plurality of devices connected to the Fibre Channel switch based on the run-time domain of the respective devices and the virtual storage area network in which the respective devices are active. A Fibre Channel identifier is stored in a memory of the Fibre Channel switch for each of the plurality of devices. The Fibre Channel identifier comprises the relative domain field value determined for the device together with area and port values for the device. The relative domain value is either a reserved domain field value for an existing virtual storage area network or any of the regular domain field values for a new virtual storage area network. The reserved domain field value is a domain field value that is not to be explicitly used in a Fibre Channel network for Fibre Channel identifiers according to the applicable Fibre Channel industry standards.