com.net2plan.examples.general.offline.nfv

Class Offline_nfvPlacementILP_v1

Object

com.net2plan.examples.general.offline.nfv.Offline_nfvPlacementILP_v1

All Implemented Interfaces:

com.net2plan.interfaces.networkDesign.IAlgorithm, com.net2plan.internal.IExternal

public class Offline_nfvPlacementILP_v1
extends Object
implements com.net2plan.interfaces.networkDesign.IAlgorithm

Algorithm based on an ILP solving several variants of the service chain allocation problem in networks with nodes equipped with IT resources (CPU, RAM, HD), and the possibility to instantiate user-defined virtualized network functions (VNFs).

The demands in the input design are service chain requests. The design produces one or more routes (just one if non-bifurcated routing option is used) from the demand input to the output nodes, traversing the resources of the required types (e.g. firewall, NAT, ...). Resource types to traverse are user defined. Each resource type is associated a cost, a capacity, and an amount of IT resources it consumes when instantiated (CPU, RAM, HD). The algorithms produces a design where all the service chain requests are satisfied, traversing the appropriate user-defined resources so that no resource is oversubscribed, and IT resources (CPU, HD, RAM) in the nodes are also not oversubscribed.

The algorithm solves an ILP based on a flow-path formulation, where for each demand, a maximum of k (user-defined parameter) minimum cost service chains are enumerated, using a variant of the k-shortest path problem. Each candidate service chain for a demand traverses the appropriate resources in the appropriate order. The formulation optimally searches among all the options for all the demands, the best global solution.

The result is returned by instanting the appropriate Demand (service chain request), Route (service chain) and Resource (virtualized functions, and It resources) objects in the output design.

The details of the algorithm will be provided in a publication currently under elaboration.

Keywords:

• JOM, NFV

Input parameters:

k: Default: 5 Maximum number of admissible service chain paths per demand shortestPathType: Value to select within {hops, km} Criteria to compute the shortest path. Valid values: 'hops' or 'km' nfvTypesInfo: Default: NAT 1 1 1 1 1 ; FW 1 1 1 1 1 Info of NFVs that could be placed, separated by ';'. Each NFV info has six space-separated parameters: 1) type, 2) cost (measured in same units as the cost of one BW unit in a link), 3) CPU use, 4) RAM use, 5) HD use, 6) capacity in same units as traffic nonBifurcatedRouting: Boolean type (default: false). True if the routing is constrained to be non-bifurcated overideBaseResourcesInfo: Boolean type (default: true). If true, the current resources in tne input n2p are removed, and for each node aone CPU, RAM and HD resources are created, with the capacities defined in input parameter defaultCPU_RAM_HD_Capacities defaultCPU_RAM_HD_Capacities: Default: 100 100 100 THe default capacity values (space separated) of CPU, RAM, HD overideSequenceTraversedNFVs: Boolean type (default: true). If true, all demands will reset the sequence of NFVs to traverse, to this (NFV types in this param are ; separated) defaultSequenceNFVsToTraverse: Default: FW NAT The default sequence of NFVs that demands must traverse solverName: Value to select within {glpk, ipopt, xpress, cplex} The solver name to be used by JOM. GLPK and IPOPT are free, XPRESS and CPLEX commercial. GLPK, XPRESS and CPLEX solve linear problems w/w.o integer contraints. IPOPT is can solve nonlinear problems (if convex, returns global optimum), but cannot handle integer constraints solverLibraryName: Default: The solver library full or relative path, to be used by JOM. Leave blank to use JOM default. maxSolverTimeInSeconds: Default: -1.0 Maximum time granted to the solver to solve the problem. If this time expires, the solver returns the best solution found so far (if a feasible solution is found) optimizationTarget: Value to select within {min-total-cost} Type of optimization target. Choose among (i) minimize the link BW plus the cost of instantiated resources (assumed measured in cost units equal to the cost of one link BW unit) maxLengthInKmPerSubpath: Default: -1.0 Subpaths (parts of the path split by resources) longer than this in km are considered not admissible. A non-positive number means this limit does not exist maxNumHopsPerSubpath: Default: -1 Subpaths (parts of the path split by resources) longer than this in number of hops are considered not admissible. A non-positive number means this limit does not exist maxPropDelayInMsPerSubpath: Default: -1.0 Subpaths (parts of the path split by resources) longer than this in propagation delay (in ms) are considered not admissible. A non-positive number means this limit does not exist

Constructor Summary

Constructors

Constructor and Description
Offline_nfvPlacementILP_v1()

Method Summary

Modifier and Type	Method and Description
String	executeAlgorithm(com.net2plan.interfaces.networkDesign.NetPlan netPlan, Map<String,String> algorithmParameters, Map<String,String> net2planParameters)
String	getDescription()
List<com.net2plan.utils.Triple<String,String,String>>	getParameters()

Methods inherited from class Object

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

Constructor Detail

Offline_nfvPlacementILP_v1

public Offline_nfvPlacementILP_v1()

Method Detail

executeAlgorithm

public String executeAlgorithm(com.net2plan.interfaces.networkDesign.NetPlan netPlan,
                               Map<String,String> algorithmParameters,
                               Map<String,String> net2planParameters)

Specified by:

executeAlgorithm in interface com.net2plan.interfaces.networkDesign.IAlgorithm

getDescription

public String getDescription()

Specified by:

getDescription in interface com.net2plan.interfaces.networkDesign.IAlgorithm

Specified by:

getDescription in interface com.net2plan.internal.IExternal

getParameters

public List<com.net2plan.utils.Triple<String,String,String>> getParameters()

Specified by:

getParameters in interface com.net2plan.interfaces.networkDesign.IAlgorithm

Specified by:

getParameters in interface com.net2plan.internal.IExternal