com.net2plan.libraries

Class FlexGridUtils

Object

com.net2plan.libraries.FlexGridUtils

public class FlexGridUtils
extends Object

Class implementing some static methods to assist in creating algorithms for flex-grid networks.

Since:

0.2.3

Author:

Pablo Pavon-Marino, Jose-Luis Izquierdo-Zaragoza

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FlexGridUtils.ModulationFormat Class to define modulation formats.

Method Summary

Methods

Modifier and Type	Method and Description
static List<Pair<Integer,Integer>>	computeAvailableSpectrumVoids(TreeSet<Integer> slotOccupancy, int totalAvailableSlotsPerFiber) Computes the list of spectral voids (list of available contiguous slots) from a slot availability vector of a path.
static int	computeMaximumRequests(List<Pair<Integer,Integer>> availableSpectrumVoids, int numSlots) Computes the maximum number of requests (each one measured in number of slots) which can be allocated in a set of spectrum voids.
static FlexGridUtils.ModulationFormat	computeModulationFormat(double pathLengthInKm, Set<FlexGridUtils.ModulationFormat> availableModulationFormats) Returns the modulation format with the maximum spectral efficiency, whereas the optical reach constraint is fulfilled, for the given path.
static FlexGridUtils.ModulationFormat	computeModulationFormat(Map<Long,Double> fiberLengthInKmMap, List<Long> seqFibers, Set<FlexGridUtils.ModulationFormat> availableModulationFormats) Returns the modulation format with the maximum spectral efficiency, whereas the optical reach constraint is fulfilled, for the given path.
static Map<Long,FlexGridUtils.ModulationFormat>	computeModulationFormatPerPath(CandidatePathList cpl, Map<Long,Double> fiberLengthInKmMap, Set<FlexGridUtils.ModulationFormat> availableModulationFormats) Returns the modulation format with the maximum spectral efficiency, while the optical reach constraint is fulfilled, for each path in a CandidatePathList object.
static int	computeNumberOfSlots(double bandwidthInGbps, double slotGranularityInGHz, double guardBandInGHz, FlexGridUtils.ModulationFormat modulationFormat) Computes the number of frequency slots required for a certain amount of bandwidth (measured in Gbps), including guard-bands.
static TreeSet<Integer>	computePathSlotOccupancy(List<Long> seqFibers, Map<Long,TreeSet<Integer>> slotOccupancyMap, int totalAvailableSlotsPerFiber) Computes the slot availability vector of a path, represented by a sequence of fibers, where each position indicates whether or not its corresponding frequency slot is available along the path.

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

computeAvailableSpectrumVoids

public static List<Pair<Integer,Integer>> computeAvailableSpectrumVoids(TreeSet<Integer> slotOccupancy,
                                                        int totalAvailableSlotsPerFiber)

Computes the list of spectral voids (list of available contiguous slots) from a slot availability vector of a path.

Parameters:

slotOccupancy - Set of slots that are already occupied

totalAvailableSlotsPerFiber - Number of slots per fiber

Returns:

List of spectrum voids, each one with a pair indicating both the initial slot id and the number of consecutive slots within the void. If no spectrum void is found, it returns an empty list

Since:

0.3.0

computeMaximumRequests

public static int computeMaximumRequests(List<Pair<Integer,Integer>> availableSpectrumVoids,
                         int numSlots)

Computes the maximum number of requests (each one measured in number of slots) which can be allocated in a set of spectrum voids.

Parameters:

availableSpectrumVoids - List of available spectrum voids (first item of each pair is the initial slot identifier, whereas the second one is the number of consecutive slots)

numSlots - Number of required slots for a reference connection

Returns:

Maximum number of requests which can be allocated in a set of spectrum voids

Since:

0.2.3

computeModulationFormat

public static FlexGridUtils.ModulationFormat computeModulationFormat(double pathLengthInKm,
                                                     Set<FlexGridUtils.ModulationFormat> availableModulationFormats)

Returns the modulation format with the maximum spectral efficiency, whereas the optical reach constraint is fulfilled, for the given path.

Parameters:

pathLengthInKm - Path length (in kilometers)

availableModulationFormats - Set of candidate modulation formats

Returns:

Best modulation format for the given path length

Since:

0.3.1

computeModulationFormat

public static FlexGridUtils.ModulationFormat computeModulationFormat(Map<Long,Double> fiberLengthInKmMap,
                                                     List<Long> seqFibers,
                                                     Set<FlexGridUtils.ModulationFormat> availableModulationFormats)

Returns the modulation format with the maximum spectral efficiency, whereas the optical reach constraint is fulfilled, for the given path.

Parameters:

fiberLengthInKmMap - Map indicating for each link its length (in kilometers)

seqFibers - (Loop-free) Sequence of traversed fibers (unchecked for conitinuity or cycles)

availableModulationFormats - Set of candidate modulation formats

Returns:

Best modulation format for the given path

Since:

0.3.0

computeModulationFormatPerPath

public static Map<Long,FlexGridUtils.ModulationFormat> computeModulationFormatPerPath(CandidatePathList cpl,
                                                                      Map<Long,Double> fiberLengthInKmMap,
                                                                      Set<FlexGridUtils.ModulationFormat> availableModulationFormats)

Returns the modulation format with the maximum spectral efficiency, while the optical reach constraint is fulfilled, for each path in a CandidatePathList object.

Parameters:

cpl - Candidate path list

fiberLengthInKmMap - Map indicating for each link its length (in kilometers)

availableModulationFormats - Set of candidate modulation formats

Returns:

Modulation format per path

Since:

0.2.3

computeNumberOfSlots

public static int computeNumberOfSlots(double bandwidthInGbps,
                       double slotGranularityInGHz,
                       double guardBandInGHz,
                       FlexGridUtils.ModulationFormat modulationFormat)

Computes the number of frequency slots required for a certain amount of bandwidth (measured in Gbps), including guard-bands.

Parameters:

bandwidthInGbps - Requested bandwidth (in Gbps)

slotGranularityInGHz - Slot granularity (in GHz)

guardBandInGHz - Guard-band size (in GHz)

modulationFormat - Modulation format

Returns:

Number of slots required to allocate the bandwidth demand

Since:

0.2.3

computePathSlotOccupancy

public static TreeSet<Integer> computePathSlotOccupancy(List<Long> seqFibers,
                                        Map<Long,TreeSet<Integer>> slotOccupancyMap,
                                        int totalAvailableSlotsPerFiber)

Computes the slot availability vector of a path, represented by a sequence of fibers, where each position indicates whether or not its corresponding frequency slot is available along the path.

Important: Loop-free paths should be employed, but it is not checked by the method.

Parameters:

slotOccupancyMap - Indicates per each fiber its slot occupancy, where already-occupied slots appear

seqFibers - (Loop-free) Sequence of traversed fibers (unchecked for conitinuity or cycles)

totalAvailableSlotsPerFiber - Number of slots per fiber

Returns:

Slot occupancy

Since:

0.3.0