Optical Network Spectrum Defragmentation via Dependency Map
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Solution Overview
Problem
Optical network spectrum fragmentation due to varying optical bandwidths and channel placements leads to decreased efficiency in data transmission, as existing methods fail to effectively defragment the spectrum without service disruptions.
Innovation Solution
A method involving assigning optical signals to frequency slots, constructing a frequency slot dependency map, and reassigned signals upon departure events to maintain network efficiency with minimal service disruption, utilizing a continuous tuning of carrier wavelengths to ensure uninterrupted transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If optical bandwidths of frequency channels are adjusted depending on signal rate and other factors, then the optical network can support varying signal rates and bandwidth requirements, but the optical spectrum becomes fragmented leading to decreased transmission efficiency
Solution Approach 1:
The system performs preliminary actions by detecting optical signal departure events before they cause spectrum fragmentation, and proactively reassigning optical signals to consolidate frequency slots. The spectrum defragmentation controller continuously monitors the optical network state and preemptively rearranges frequency slot assignments to prevent fragmentation, thereby maintaining transmission efficiency while preserving bandwidth adaptability.
Solution Approach 2:
The system implements dynamic frequency slot reassignment based on real-time network conditions. When optical signals are added or removed, the controller dynamically adjusts frequency slot assignments to consolidate spectrum usage. This dynamic adaptation allows the network to maintain both bandwidth flexibility and transmission efficiency by continuously optimizing spectrum allocation rather than using static assignments.
2Productivity
If optical signals are reassigned to different frequency slots to defragment the spectrum, then transmission efficiency is improved, but service disruptions may occur during the reassignment process
Solution Approach 1:
The system performs preliminary actions by pre-planning frequency slot reassignments and preparing the network state before actual signal migration. The controller calculates optimal target frequency slots and prepares cross-connect configurations in advance, then executes the reassignment in a coordinated manner to minimize service disruption. This preliminary preparation ensures that service continuity is maintained while achieving spectrum defragmentation.
Solution Approach 2:
The system maintains continuous optical signal transmission during the frequency slot reassignment process. By using optical cross-connects that can switch signals without converting to electrical domain, and by coordinating the reassignment to occur during low-traffic periods or using protection switching mechanisms, the useful action of data transmission continues uninterrupted, thereby maintaining service reliability while improving transmission efficiency.
3Reliability
If frequency slot dependency maps are constructed and used for signal reassignment, then spectrum defragmentation is achieved with minimal service disruption, but the system complexity increases
Solution Approach 1:
The control system is segmented into modular functional components: a spectrum defragmentation controller that constructs and maintains frequency slot dependency maps, optical cross-connects that execute switching operations, and monitoring modules that detect signal departure events. Each component performs a specific function independently, which reduces overall system complexity by avoiding monolithic design while still achieving reliable service continuity through coordinated operation of these segmented modules.
Solution Approach 2:
The frequency slot dependency map acts as an intermediary data structure that mediates between the control logic and the physical optical network state. Rather than directly managing complex switching operations, the controller uses this intermediate representation to plan and coordinate reassignments. This intermediary layer simplifies the control logic by providing an abstract view of spectrum allocation and dependencies, reducing the complexity of the overall control system.
Data Source
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AI summary
According to an aspect of an embodiment, a method of spectrum defragmentation in an optical network may include assigning an optical signal within an optical network to a first frequency slot that spans a first portion of an optical spectrum of the optical network. The method may also include constructing a frequency slot dependency map based on the assignation of the optical signal to the frequency slot. The method may also include reassigning, as a result of an optical signal departure event, the optical signal to a second frequency slot based on the frequency slot dependency map. The second frequency slot may span a second portion of the optical spectrum of the optical network.