1 Davis Social Links S. Felix Wu Computer Science Department University of California, Davis [email protected] wu

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Davis Social Links

S. Felix WuComputer Science DepartmentUniversity of California, Davis

[email protected]://www.cs.ucdavis.edu/~wu/

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Internet Architecture & Routing

Applications with Tests

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Internet Architecture & Routing

• Any identity (email address, IP, url) can communicate with any one else.– Email, web, bittorrent, warcraft, skype…

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Social-Control Routing

Applications with Tests

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3

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The value of the “Network”

• A concern about a network losing its “value”– while we are unsure about how to quantify the true value…

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Open Issues

• What is the “value” of this social network?

• How would this “value” be distributed and allocated to each individual peers?

• MySpace, Facebook, LinkedIn didn’t define the “game” for network formation and value allocation.– But, it is important to design the game such that the OSN will eventually converge to a state to best support the communities.

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Social Network Games

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Fighter’s Club

• A Coalition game ~ like Warcraft• Team members who are Facebook friends receive higher fighting powers

• ~1400 new friendships established daily

• ~10% of users with >95% friendships purely based on this game.

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Facebook versus Personal Web Site

• WWW: everybody can see it• Facebook: a selected set of people on your social network can see it

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Activities, Knowledge Sharing, and Social Relationship

Scalability, Privacy, Trust, Robustness,Performance…

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Social Network Applications

• Social-based collaborative filtering

• Recommendation• Privacy-control• Advertising

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Urgent! Please contact me!

FROM:MR.CHEUNG PUIHang Seng Bank LtdSai Wan Ho Branch171 Shaukiwan RoadHong Kong.

Please contact me on my personal box [[email protected]]

Let me start by introducing myself. I am Mr. Cheung Pui, director of operations of the Hang Seng Bank Ltd,Sai Wan Ho Branch. I have a obscured business suggestion for you.

Before the U.S and Iraqi war our client Major Fadi Basem who was with the Iraqi forces and also business man made a numbered fixed deposit for 18 calendarmonths, with a value of Twenty Four millions Five Hundred Thousand United State Dollars only in my branch. Upon maturity several notice was sent to him,…

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http://www.ebolamonkeyman.com/cheung.htm

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Pick your favor Spam Filter(s)

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This was considered a spam!

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This was considered a spam!

Sometimes, the cost of False Positive may be very high…

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The Implication of FP’s

• Spam-filters have to be conservative…

• We will have some false negatives in our own inboxes.

• We will use our own time to further filter..– For me, 1~2 seconds per email

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The emails I received just THIS morning…

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You have about 1 second to decide……

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“ Social Spams”

• They might not be spams as we often overlooked the social values of them!

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Motivations

• The value of social communication– To leverage– To protect

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Communicate: [A, D]

A

B

C

D

As long as “A” knows “D’s routable identity”

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Hijackable Routable Identify

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[A,D] + social context

A

B

C

D

“A” has to explicitly declare if there is any social context under this communication activity with “D”!

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Internet & Routable Identity

• URL, IP address, email,….– For ANYWHERE in the Internet

• Without Routable Identity– Only available to certain parts of Social Networks

• Using OSN to perform access control

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Who is Salma?

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Who is Salma?

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Who is Salma?

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My message to Salma

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The Social Path(s)

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“ Optimality”

• Not necessarily “the shortest path”– Social context consideration

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More Examples

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CyrusDSL

• How do we accomplish these features?

• How do we realize the concepts scaleable?

• How will this system work against spams?

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Just a couple issues …

• How to establish the social route?– How would “A” know about “D” (or “D’s identity”) ?

• How to maintain this “reputation network”?– MessageReaper: A Feed-back Trust Control System (Spear/Lang/Lu)

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[A,D] + social context

A

B

C

D

“A” has to explicitly declare if there is any social context under this communication activity with “D”! But, “D” only cares if it is from “C” or not!

??

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Search on “OSN”

• How to get to from ?

• The Small world model– 6 degree separation (Milgram, 1967)– “existence of a short path”– How to find the short path? (Kleinberg, 2000)

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Re-wiring (Watts/Strogatz)

Trade off between D and Ccluster !

Structured/Clustered

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Routing in a Small World

• Common question: do short paths exist?

• Algorithmic question: assuming short paths exist. How do people find them?

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Kleinberg’s results

A decentralized routing problem– For nodes s,t with known lattice coordinates, find a short path from s to t.

– At any step, can only use local information,

– Kleinberg suggests a simple greedy algorithm and analyzes it:

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Kleinberg’s Model

• Use only Local information, except the distance to the target.– However, what is the “global distance” in cyber space? Yet, the assumption behind is that the “edges” depend on the “relative distance”.

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• How will we tell whether the relative distance between X&Y is closer than X&Z?– X, Y, Z (assuming they are all direct friends to each other)

• One simple idea: “Keyword intersection”– KW(X), KW(Y), KW(Z)– 1/(#[KW(a) KW(b)] + 1)

– Will this work? How about global distance?

X, Y, and Z

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Similarity

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Similarity

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Social Route Discovery for A2D

A

B

C

D

Let’s assume A doesn’t have D’s “routable identity”Or, “D” doesn’t have a global unique identity!Then, how can we do A2D?

??

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Finding

A

B

C

D

A2D, while D is McDonald’s!D would like “customers” to find the right route.“idea: keyword propagation” e.g., “McDonald’s”

??

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Announcing

A

B

C

D

Hop-by-hop keyword propagation

K: “McDonald’s”

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Announcing

A

B

C

D

Hop-by-hop keyword propagation

K: “McDonald’s”

K: “McDonald’s”

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Announcing

A

B

C

D

Hop-by-hop keyword propagation

K: “McDonald’s”

K: “McDonald’s”

K: “McDonald’s”

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Announcing

A

B

C

D

Hop-by-hop keyword propagation

And, I know I am doing FLOODING!!

K: “McDonald’s”

K: “McDonald’s”

K: “McDonald’s”

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Now Finding

A

B

C

D

Search Keyword: “McDonald’s”A might know D’s keyword via two channels(1) Somebody else (2) From its friendsQuestions: does D need an identity? Scalable?

K: “McDonald’s”

K: “McDonald’s”

K: “McDonald’s”

Q: McDonald’s

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Application Tests

• Example 1: credential-oriented– “PKI certificate” as the keyword– If you can sign or decrypt the message, you are the ONE!

• Example 2: service-oriented– Service/protocol/bandwidth support

• Example 3: offer-oriented– Please send me your coupons/promotions!

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“ Routable Identity”

• Application identity =M=> Network identity

• Network identity =R=> Network identity

• Network identity =M=> Application identity

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“ App/Route Identity”

• Application identity =M=> Network identity

• Network identity =R=> Network identity• Network identity =M=> Application identity

• Keywords =(MF-R)=> “Multiple Paths”• Application identity selection• Network route selection

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Finding

Search Keyword: “McDonald’s”Questions: is this the right Felix Wu’s?How to avoid/control flooding??

A

B

C

D

K: “McDonald’s”

K: “McDonald’s”

K: “McDonald’s”

Q: McDonald’s

Application Test

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Scalability - Avoid the Flooding

• As it is, every keyword will need to be propagated to all the nodes/links (but the same keyword will be propagated through the same link once possibly with different policies).

• The issue: “who should receive my keywords?”

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in Community of Davis

A

B

C

D

Who should receive the keyword announcement for “McDonald’s”?

??

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as the Social Peer

• Attributes:– {McDonald’s Express, 640 W Covell Blvd, # D, Davis, (530) 756-8886, Davis Senior High School, Community Park, North Davis}

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“ Per-Keyword Policy”

• For each keyword, we will associate it with a propagation policy: [T, N, A]– T: Trust Value Threshold– N: Hop counts left to propagate (-1 each step)

– A: Community Attributes

• Examples:– [>0.66, 4, “Davis”] K via L1

– [>=0, , ] K via L2

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Scalability & Controllability

• McDonald’s doesn’t want to flood the whole network– It only wants to multicast to the “Target set” of customers

• And, it only wants this target set of users being able to use that particular keyword to contact.– Receiver/owner controllability

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Social/Community Attributes

A

B

C

D

Who should receive the keyword announcement for “McDonald’s”? Answer:

??

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Community

A

B

C

D

??

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Community

• A connected graph of social nodes sharing a set of community attributes

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Community

A

B

C

D

??

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Social/Community Attributes

A

B

C

D

Who should receive the keyword announcement for “McDonald’s”? Answer: but not ALL

??

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Community

A

B

C

D

??

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Network Formation

A

B

C

D

??

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Network Formation

A

B

C

D

??

Both A & C: why would A & C be willing to establish a direct friendship?

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Open Issues

• What is the “value” of this social network?

• How would this “value” be distributed and allocated to each individual peers?

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Fighter’s Club

• A Coalition game ~ like Warcraft• Team members who are Facebook friends receive higher fighting powers

• ~1400 new friendships established daily

• ~10% of users with >95% friendships purely based on this game.

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[email protected] +

A

B

C

D

Who should receive the keyword announcement for “[email protected]”? Answer:

??

K: “wu@…” + Policy

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Even if “A” claims

A

B

C

D

Who should receive the keyword announcement for “[email protected]”? Answer:

??

K: “wu@…”

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“ B” can help…

A

B

C

D

What is B’s incentive? What is B’s risk?

??

K: “wu@…”

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Message Value & Prioritization

Application IDS

Link RanksReputationIncentives

Other Trust Metrics

[good, bad] messages

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Reputation

• Adding “Trust” as another consideration in routing

• Per-packet Reputation Update• Fast Stabilization• Mobility without per-hop authenticated Global/Unique Network layer Identities

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Reputation on Feed-back

A

B

C

D

“D” is the one to decide whether the message from A/B/C is good or bad!

??

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One Route path from A to D

Pkt[a>d]

End2End Trust: “is this really from A?”

RoutePath Trust: “Should this path be used?”

A B C D

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Basic Assumption about the Link

Pkt[a>d]

B & C have a way to decide whether they should establish a link between them, and they can authenticate each other:

Secure MAC authenticationSocial Links in OSNReputation-based AuthenticationSybil Attack robustness

A B C D

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The Attack Model• Does the receiver really like this packet being delivered to me over a route path of links:– Corrupted information– Spam– An incorrectly E2E-Authenticated packet– Malware

• Assumption: the receiver has its own security policy to determine whether it like the packet/message or not!

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D decides, and rewards/punishes…

A B C DPkt[c>d]

Trust(D>C)Pkt[bcd]

Trust(C>B)Pkt[abc]

Trust(B>A)Pkt[ab]

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Trust Structure

We want to stabilize these decentralized values such that they can be used to effectively choose the “best” route.

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Game Theory Analysis

A B C DPkt[c>d]

Trust(D>C)Pkt[bcd]

Trust(C>B)Pkt[abc]

Trust(B>A)Pkt[ab]

Value Allocation: if a bad message is delivered, how should we distribute the “damage” along the route path?

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Trust Structure as the Utility

We want to stabilize these decentralized values such that they can be used to effectively choose the “best” route.

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Three Trust Values per Relationship

• Ta(u,v): u is directly connected to v. How much u trusts v?

• Ainit: v, as the initiator, sends a packet to u.

• Afwd: v forwards a packet to u . I.e., v is not the initiator of the packet.

• Art: sends a packet to, and, v forwards that packet to one of its other neighbors. And, the packet eventually reaches the destination.

u v

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Example

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Routing with Trust

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1000 nodes, 20% bad

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1000 nodes, 10%/40% bad

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Increasing the Spammers

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Orkut (15329 nodes)

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Open Issues

• What is the “value” of this social network?

• How would this “value” be distributed and allocated to each individual peers?

• MySpace, Facebook, LinkedIn didn’t define the “game” for network formation and value allocation.– But, it is important to design the game such that the OSN will eventually converge to a state to best support the communities.

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Social Network Development

• Social Graph• User-defined keywords and attributes

• DSL server • Trust Routing Protocol

DSL

Facebook

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DSL is an old idea!

We, as human, have been using similar communication principles. Maybe it is a good opportunity to re-think about our cyber communication system.

Identity is a per-application, context-oriented, and sometime relative issue.

Forming cyber communities of interests for application.

A B

A BF

FF

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DSL, Facebook, AL-BGP and GENI

Facebook

AL-BGP over GENI/PlanetLab

http://www.geni.net/DSLport

Each DSL/FB user should select a “closer” GENI entrance as www.geni.net. In other words, we might need to set up DNS records correctly.

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DSL Architecture

AL-BGP

DSL

Applications with Tests

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Link

Applications with Tests

12 3

4

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AS-oriented Social Mapping

Applications with Tests

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Control versus Data Path

Applications with Tests

data path

control path

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Social-Control Routing

Applications with Tests

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3

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Easy to Send & Receive

•Easy for both the good users and the spammers. (fair simplicity)

•The spammers abuse the “sending” right, while the good users have very limited options to counter back.–how easy can we change our email address?

–how often do we need to do that?•A “receiver” or “the owner of the identity” should have some control.–But, that means also “burden” to the users.

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Easy to Send & Receive

•Easy for both the good users and the spammers. (fair simplicity)

•The spammers abuse the “sending” right, while the good users have very limited options to counter back.–how easy can we change our email address?

–how often do we need to do that?•A “receiver” or “the owner of the identity” should have some control.–But, that means also “burden” to the users.

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Davis Social Links

• Peer-to-Peer System (P2P)– How human socially communicate?

• Online Social Network (OSN)– How to utilize OSN to enhance communication?

– How to have a securer OSN?

• Autonomous Community (AC)– How to build/develop more effective community-based social networks?

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AcknowledgementA B

A BF

FF