io.kgraph.library

Class SybilRank

java.lang.Object

io.kgraph.library.SybilRank

All Implemented Interfaces:

ComputeFunction<Long,SybilRank.VertexValue,Double,Double>

public class SybilRank
extends Object
implements ComputeFunction<Long,SybilRank.VertexValue,Double,Double>

This is an implementation of the SybilRank algorithm. In fact, this is an extension of the original SybilRank algorithm published by Cao et al at NSDI'12. This version of the algorithm assumes a weighted graph. The modified algorithm has been developed by Boshmaf et al.

Author:

dl

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	SybilRank.Initializer This class is used only to initialize the rank of the vertices.
static class	SybilRank.SybilRankComputation This class implements the main part of the SybilRank algorithms, that is, the power iterations.
static class	SybilRank.TrustAggregation This computation class is used to calculate the aggregate number of trusted nodes.
static class	SybilRank.VertexValue Represents the state of a vertex for this algorithm.

Nested classes/interfaces inherited from interface io.kgraph.pregel.ComputeFunction

ComputeFunction.Aggregators, ComputeFunction.Callback<K,VV,EV,Message>, ComputeFunction.InitCallback, ComputeFunction.MasterCallback, ComputeFunction.ReadAggregators, ComputeFunction.ReadWriteAggregators

Field Summary

Fields

Modifier and Type	Field and Description
static String	AGGREGATOR_NUM_TRUSTED Name of aggregator used to calculate the total number of trusted nodes.
static String	ITERATION_MULTIPLIER Property name for the iteration multiplier.
static int	ITERATION_MULTIPLIER_DEFAULT Default multiplier for the iterations.
static String	TOTAL_TRUST Property name for the total trust.

Constructor Summary

Constructors

Constructor and Description
SybilRank()

Method Summary

Modifier and Type	Method and Description
void	compute(int superstep, VertexWithValue<Long,SybilRank.VertexValue> vertex, Iterable<Double> messages, Iterable<EdgeWithValue<Long,Double>> edges, ComputeFunction.Callback<Long,SybilRank.VertexValue,Double,Double> cb) The function for computing a new vertex value or sending messages to the next superstep.
static double	computeDegree(Iterable<EdgeWithValue<Long,Double>> edges) This method computes the degree of a vertex as the sum of its edge weights.
protected long	getTotalNumVertices(ComputeFunction.ReadAggregators aggregators)
void	init(Map<String,?> configs, ComputeFunction.InitCallback cb) Initialize the ComputeFunction, this is the place to register aggregators.
void	masterCompute(int superstep, ComputeFunction.MasterCallback cb) A function for performing sequential computations between supersteps.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.kgraph.pregel.ComputeFunction

postSuperstep, preSuperstep

Field Detail

TOTAL_TRUST

public static final String TOTAL_TRUST

Property name for the total trust.

See Also:

Constant Field Values

ITERATION_MULTIPLIER

public static final String ITERATION_MULTIPLIER

Property name for the iteration multiplier.

See Also:

Constant Field Values

ITERATION_MULTIPLIER_DEFAULT

public static final int ITERATION_MULTIPLIER_DEFAULT

Default multiplier for the iterations.

See Also:

Constant Field Values

AGGREGATOR_NUM_TRUSTED

public static final String AGGREGATOR_NUM_TRUSTED

Name of aggregator used to calculate the total number of trusted nodes.

See Also:

Constant Field Values

Constructor Detail

SybilRank

public SybilRank()

Method Detail

computeDegree

public static double computeDegree(Iterable<EdgeWithValue<Long,Double>> edges)

This method computes the degree of a vertex as the sum of its edge weights.

Parameters:

edges - the edges

Returns:

the degree

init

public void init(Map<String,?> configs,
                 ComputeFunction.InitCallback cb)

Description copied from interface: ComputeFunction

Initialize the ComputeFunction, this is the place to register aggregators.

Specified by:

init in interface ComputeFunction<Long,SybilRank.VertexValue,Double,Double>

Parameters:

configs - configuration parameters

cb - a callback for registering aggregators

masterCompute

public void masterCompute(int superstep,
                          ComputeFunction.MasterCallback cb)

Description copied from interface: ComputeFunction

A function for performing sequential computations between supersteps.

Specified by:

masterCompute in interface ComputeFunction<Long,SybilRank.VertexValue,Double,Double>

Parameters:

superstep - the superstep

cb - a callback for writing to aggregators or halting the computation

compute

public void compute(int superstep,
                    VertexWithValue<Long,SybilRank.VertexValue> vertex,
                    Iterable<Double> messages,
                    Iterable<EdgeWithValue<Long,Double>> edges,
                    ComputeFunction.Callback<Long,SybilRank.VertexValue,Double,Double> cb)

Description copied from interface: ComputeFunction

The function for computing a new vertex value or sending messages to the next superstep.

Specified by:

compute in interface ComputeFunction<Long,SybilRank.VertexValue,Double,Double>

Parameters:

superstep - the count of the current superstep

vertex - the current vertex with its value

messages - a Map of the source vertex and the message sent from the previous superstep

edges - the adjacent edges with their values

cb - a callback for setting a new vertex value or sending messages to the next superstep

getTotalNumVertices

protected long getTotalNumVertices(ComputeFunction.ReadAggregators aggregators)