Expediting Searching Processes via Long Paths in P2P Systems

05/30 IDEA Lab

Outline

Motivations Related Work Our Approach

Flow Chart of Long Path Establishment

Detailed Steps

Motivations

Efficient indexing Efficient searching

Lower searching time Lower internet traffic Lower query messages

Use long paths to connect high responding peers

P2P Overview

Centralized

Structured

P2P

DHT

Decentralized

Napster

Unstructured

CANChordPastryTapestry

GnutellaFreenet

Yes No

Unstructured P2P: Gnutella Flooding

D

C

BE

JF

I

H

A

G

N neighbors: N duplicated messages

MessageTraffic

Related Work

Random Walk Sequential search

MessagesSearch time

Related Work

Random Walk Sequential search

Directed Flooding Query logs

ASeparate interest categories

HistoryArt Science

B

Harry PotterDistributeddatabases

Warcraft

MessagesSearch time

Related Work

Random Walk Sequential search

Directed Flooding Query logs

Overwhelmed links High update cost Not for various query types

A

HistoryArt Science

Intuitions Goal

Link # Fast locate various contents

Small communication cost Searching efficiency

Traffic Query messages Search time Hop #

Method Set up long paths

Our Approach

Set up long paths Assumption

Each peer will calculate its Self Evaluation Score

Capable peer Self Evaluation Score > threshold

Set up Long Paths

A

Capable peer

Our Approach

Set up long paths Assumptions

Each peer will calculate its Self Evaluation Score

Each peer has to share files and knows his neighbors’ similarities

Our Approach

Shared files Class types and percentages of

each neighbor Knows his neighbors’ similarities

Jazz 80%Pop 15%

Classical 5 %

Pop 60%Rock 30%

Classical 10 %

Rock 70%Jazz 20%

Pop 10 %

Set up Long Paths

A

Cluster

Capable peer

ClusterCluster

Cluster

Cluster

Cluster

Cluster

Neighbor list

Set up Long Paths

A

Cluster

Capable peer

ClusterCluster

Cluster

Cluster

Cluster

Cluster

Neighbor list

scorescore

score

score

score

score

score

score

score

Set up Long Paths

A

Cluster

Capable peer

ClusterCluster

Cluster

Cluster

Cluster

Cluster

scorescore

score

score

score

score

score

score

score

1

2

3

41

5

2

3

6

Our Approach

Set the long path candidate peers according to scores Marker 1

Set up Long Paths

A

Cluster

Capable peer

ClusterCluster

Cluster

Cluster

Cluster

Cluster

scorescore

score

score

score

score

score

score

score

1

2

3

4

5

2

3

6

Flow Chart of Long Path Establishment

Capable Peer Cluster neighbors

Select candidates

Pass Flag

Listening all flags

Update flags info

Timeout?YES

Long path?

Establish Long path

NO

Direct or indirectCandidate?

YES

NO

Send flag to last hop location

Direct

Indirect

Neighbor PeerReceive Flag

Update flag into to issuer

Far enough? ORNear cluster boundary?

Select candidate

NO previous one

Pass Flag

Initial flag Resent flag

Establish long path

Select Candidates

Scoring mechanism The total score: direction of

searching Self evaluation score

Uptime Link # Load Balance

Peer evaluation score Query support rate Query latency

Calculate Self Evaluation Score Criteria

Uptime Link # Load Balance

50

Calculate Self Evaluation Score Criteria

Uptime Link # Load Balance

score1

0

normalized

50

Calculate Self Evaluation Score Criteria

Uptime Link # Load Balance

1 2 3 4 5 6 7

0.2

0.4

0.6

0.8

1

suggestioncurrent max

score

normalized

Calculate Peer Evaluation Score

Query support rate Query latency

Communication power of a peer

Capability of this network

responding time (second)

score

normalized

1

0

The total score

( ) ( )

( )

( 1)

TotalScore N SelfEvaluationScore N

PeerEvaluationScore N

( 0.5, 0.5) Initial value:

Thank you for your attentions!!