Continuous Queries in P2P Networks

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2005/11/09

• Continuous Queries in P2P Networks

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Motivation
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Motivation - Cardinality
How many people are currently listening POP music?
POP
POP
Classic
Result 2
Rock
Classic
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Motivation Top-K
What is the Top-2 Songs?
Because of you by Kelly Clarkson
Shake It Off by Mariah Carey
Wake Me Up When September Ends by Green Day
Wake Me Up When September Ends by Green Day
Because of you by Kelly Clarkson
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Motivation Top-K
What is the Top-2 Songs?
Because of you by Kelly Clarkson
Shake It Off by Mariah Carey
Wake Me Up When September Ends by Green Day
Wake Me Up When September Ends by Green Day
Because of you by Kelly Clarkson
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Motivation Social Network
I want to make friends who have similar interests
as I have
POP
POP
Classic
Rock
Classic
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Motivation Social Network
I want to make friends who have similar interests
as I have
POP
POP
Classic
Rock
Classic
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Motivation Social Network
I want to make friends who have similar interests
as I have
POP
POP
Classic
Rock
Classic
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Motivation Social Network
I want to make friends who have similar interests
as I have
POP
POP
Classic
Rock
Classic
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Motivation - Ontology
Search Shake Your Bon Bon by Ricky Martin
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Motivation - Ontology
Search Shake Your Bon Bon by Ricky Martin
I have Shake Your Bon Bon
Sorry, I have none
I do have this song but its name is Martins Ass
Dude, get away from me
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Motivation - Ontology
Search Shake Your Bon Bon by Ricky Martin
Ontology
The result of exact matching 1 By we want to
get the actual result 2
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Continuous Queries

• Cardinality
• Top-K
• Social network
• Ontology

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Cardinality

• The state-of-the-art
• Aggregation in P2P system
• Montresor et al. DSN'04
• Epidemic, adaptive
• Aggregation with streaming data
• Das et al. VLDB04
• Global knowledge of frequent items

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Cardinality (Contd.)

• As far as we know, there is no study focus on
  this issue in P2P environment with streaming data
• Progress after our summer presentation
• Use statistics distribution to estimate changes

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Top-K

• The state-of-the-art
• Traditional Top-K problem
• Combine information for database systems Fagin
• Approximation on data streams
• Proposed for data streams under guaranteed
  tolerance, but cant be deployed to P2P.
• Super peer based Top-k in P2P
• Iteratively query
• Locality was mentioned, but the method is
  straight-forward

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Top-K (Contd.)

• Assumptions
• Based on superpeer-structured P2P networks due to
  the heterogeneity of peers
• Each super-peer would maintain a routing table
  and some metadata for Top-k query

P
P
P
SP1
P
P
SP2
SP4
P
P
SP3
P
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Top-K (Contd.)

• Problem
• Query whom? ?Locality
• space
• Interest
• Query routing (routing table)
• Reduce the size of table
• Minimize the communication
• peers update occurs
• load balance

Type
Node
T1
SP2
T1
SP3
T2
SP4
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Social network Ontology

• The state-of-the-art
• Similarity computing
• Compute the similarity between two nodes/peers,
  and fix-point scores will be assigned
• ?

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Social network Ontology

• ?
• Our thoughts
• Using some hierarchical domain structures
• Ontology / classification

Rock
Avril Lavigne
Bon Jovi
A a1, a2 B a3, a4 C a1, b1, b2
a1
a2
a3
a4
b1
b2
b3
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Thank You!
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What is ontology
Back

• A formal, explicit specification of a shared
  conceptualization

Class
attribute
Object
Object
relation
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Example
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Example
Ballet
Kung Fu
Swim
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Example
Ballet
Swim
Kung Fu
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