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MultiNetwork Information Dissemination

Nalini Venkatasubramanian

Dept. of Computer ScienceCERT/ UC Irvine

UCI: Valentina Bonsi, Mayur Deshpande, Hojjat Jafarpour, Kyungbaek Kim, Sharad Mehrotra, Do Minh Ngoc, Mirko

Montanari, Jeanettte Sutton, Kathleen Tierney, Bo Xing…….&

City of LA Emergency Preparedness Dept.City of Ontario, CA

Center for Emergency Response Technologies CERT Mission

lead research, technology development IT to improving emergency response. forum for collaboration between academia, industry, and government

Interdisciplinary researchers Computer Science, Social Science, Engineering

Close partnerships with local & state agencies, industry. Cities of LA/SD/Ontario/Rancho, OCFA, LA County Fire…

Responsphere – A campus-wide testbed for technology testing

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Industrial Partners5G Wireless

Broad-ranged IEEE 802.11 networking

AMDCompute Servers

Apani NetworksData security at layer 2

Asvaco1st responder (LAPD), and threat

analysis software

BoeingCommunity Advisory Board

Member

CanonVisualization equipment SDK

ConveraSoftware partnership

Cox CommunicationsBroadcast video delivery

D-LinkCamera Equipment and SDK

Ether2Next-generation ethernet

IBMSmart Surveillance Software (S3)

and 22 e330 xSeries servers

ImageCat, Inc.GIS loss estimation in emergency

response

MicrosoftSoftware

PrintronixRFID Technology

The School Broadcasting Company

School based dissemination

Vital Data TechnologySoftware partnership

Walker WirelessPeople-counting technology

Government PartnersCalifornia Governor’s Office of Emergency

Services

California Governor’s

Office of Homeland Security

City of Champaign City of Dana Point

City of Irvine City of Los Angeles

City of Ontario

Fire DepartmentCity of San Diego

Department of Health and Human Services – Centers

for Disease Control

Lawrence Livermore

National Laboratory

Los Angeles CountyNational Science

Foundation

Orange CountyOrange County Fire

Authority

U.S. Department of

Homeland Security

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Next Generation Alerting and Warning Project

Dissemination in

the Large

Content LayerResearch

Systems and Deployments

Delivery Layer Research

Wired Networks

Wireless Networks

CrisisAlert DisasterPortalEfficient Publish

Subscribe

Content Customization

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T: 0 45 secs

Scenario: Earthquake Dissemination Timeline

Warning Damage Analysis & Response

Disseminating Public Information

2-5 mins

5-60 mins

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Flash Dissemination in Wired Networks

Early Earthquake Warning Systems (0-45 seconds) Sound sirens, backup data, avoid bridges Goals: Speed and reliability

USGS Shakecast (2-5 minutes) Highly Detailed GIS data Partial infrastructure availability

Information Portals(>1 hour) Up-to-date Information from authoritative

sources Website under heavy load: Spikes crash

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Flash Dissemination in the Large (Wired Networks)

Early Earthquake Warning Systems (0-45 seconds) Sound sirens, backup data, avoid bridges Goals: Speed and reliability Approach: Reliable ALM Protocols over

P2P Networks (FareCAST)

USGS Shakecast (2-5 minutes) Highly Detailed GIS data Partial infrastructure availability Approach: Gossip-Based Random Walker

Protocols on P2P Networks (CREW)

Information Portals(>1 hour) Up-to-date Information from authoritative

sources Website under heavy load: Spikes crash Approach: P2P WebServers (Flashback)

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FaReCast : Fast and Reliable Application Layer Multicast

1. Forest-Based M2M ALM StructureMultiple Fan-In – for reliabilityMultiple Fan-Out – for speed↑Path Diversity, ↑ reliability, ↑speed

1. Forest-Based M2M ALM StructureMultiple Fan-In – for reliabilityMultiple Fan-Out – for speed↑Path Diversity, ↑ reliability, ↑speed2. Multidirectional

MulticastingDon’t fix, trigger sends judiciouslyBackup Dissemination L2L (Leaf-to-Leaf) Dissemination

2. Multidirectional MulticastingDon’t fix, trigger sends judiciouslyBackup Dissemination L2L (Leaf-to-Leaf) Dissemination

Traditional Tree : Multiple Fan-Out Efficient and Fast, Single Point of FailureNo time to recover, ack/resend

Traditional Tree : Multiple Fan-Out Efficient and Fast, Single Point of FailureNo time to recover, ack/resend

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FaReCast: Fast Reliable Appl. Layer Multicast

No significant increase in latency

for over 99% of nodes

No significant increase in latency

for over 99% of nodes

100%reliability under

40% of failed nodes

100%reliability under

40% of failed nodes

Simulation with 100,000 nodes

Simulation with 100,000 nodes

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Richer Information (2-5 minutes)CREW (Concurrent Random Expanding Walkers) Protocol

1231

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3

4

2

6

1

5

3

4

2

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Basic Idea: Servers ‘serve’ data to only a few clients Who In turn become

servers and ‘recruit’ more servers

Split data into chunks Chunks are

concurrently disseminated through random-walks

Self-scaling and self-tuning to heterogeneity

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CREW Protocol: Latency, Reliability

RapIDInformation Reintegration Module

Chunk Forwarding Module Neighbor Maintenance Module

CORBA-based Middleware (ICE)

Network / OS

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An Hour and Beyond…Flashback: Scalable Dissemination of Web Pages

Spike loads crash Web sites Slashdot, Disaster-Portals

A Distributed Web Server Browsers that want the web-

page are now collectively behaving as a P2P webserver No intermediaries, setup

Medium Size Content 100KB – 1-2MBs

Repeated catastrophes!!! 10 secs – user interaction,

peer download times Roulette Protocol

Grandma-proof! Setup/configure, firewalls Diverse OS, browsers

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Performance Measurement: Basic Scalability

Flashback is highly scalable HTTP download time is linear in number of nodes Flashback download time is Log in number of nodes

Test Setup Web-server hit with a “one-shot” number of clients; server 800Kbps BW Average time for a client to get the whole file measured

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Fast, Reliable Dissemination in Wireless Networks

The problem: Broadcast of rich content data over wireless networks at crisis site

Delayed Dissemination in Disconnected Networks

Hybrid Networks for Reachability and Scalability

GoalsGoals

Reliability

Timeliness

Message Efficiency

Instant Disseminationin Connected Networks

Cellular, WiFi, MANETS, DTNs, Mesh

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RADCAST: Flash Broadcast in MANETS Concurrent dissemination of awareness and content

Data diffusion: based on a mix of push/pull (Pryer) Awareness assurance: network traversal using walkers (Peddler)

Problem: fast network traversal Minimizing cover time, termination time and transmission overhead

AwarenessAssurance

Fragmentation

DataDiffusion

ReliableContent

Dissemination

Metadata

Content Data

{{

{concurrent

Walker

Walker

concurrent

Assures reception

Pull

Push

concurrent

GuidesRetrievesmissing

Spreads

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Sticker: A Protocol for Spatial Dissemination in Disconnected Networks

Replication

ForwardingContext Sens-ing & Collection

{Purging

Fixed Number of Distinct Copies

Location-Closeness Based

Aliveness-Signi-ficance Based

Devices cache and carry messages for others,

Messages exchanged during encounters

Problem: Post messages to a geographic location without infrastructure support h

Instant Mesh Networks

Network Backhaul

Mesh Backbone

Client Latency

MobileClients

Backbone Latency Gateway

Data Network

Dynamically deployed mesh networks for providing short-term infrastructure coverage at incident/event sites

• Fast, easy deployment• Expanded coverage• External information

Gateway Designation in Instant Mesh Networks

Given:Given:

GoalGoal::

OptimizeOptimize::

A connected network formed by stationary mesh routers An initiator mesh router

Distributedly find the mesh router with maximum centrality and report it to the initiator mesh router

Transmission Efficiency: least number of transmissions Time Efficiency: least execution time

Closeness Centrality:Closeness Centrality:1

( )( , )c

t V

nC v

d v t

1( )

max ( , )g

t V

C vd v t

Graph Centrality:Graph Centrality:

-- Capturing average backbone latency-- Capturing max backbone latency

Measured based on link quality metrics

The Problem:To determine which mesh router in a given mesh backbone should serve as the gateway, so that backbone latency is minimized.

FACE: An Approximation Algorithm

CentralityMeasuring

ExtremaFinding

GatewayDesignation{

Popping up the maximum centrality along a spanning

tree rooted at initiator (PST)

Popping up the maximum centrality along a spanning

tree rooted at initiator (PST)

Centrality Approximation using spanning tree root/leaves as sample

points

Centrality Approximation using spanning tree root/leaves as sample

points

Distance Notification through Spanning trees (SSTs) for centrality

calculation

Distance Notification through Spanning trees (SSTs) for centrality

calculation

FACEFACEFACEFACE

Centrality Approximation:Centrality Approximation:Using randomly picked nodes as sample points to approximate centrality [Eppstein SODA 2001]- additive error based on number of sample points

Some Performance Results

The FACE-designated gateways significantly enhances the timeliness of disseminations of external information.

Impact of FACE on Inbound dissemination latencies (32KB data)

Mesh Network Deployments

Commercial mesh routers not good enough

5X improvement with new antenna technology

Better signal coverage better building penetration

• Some Setup effort required • Not always feasible• Vulnerable to hardware failures

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In the future

Research Geographically Correlated Failures Uncertainty and Correlations in Information Dissemination Understanding/Incorporating Social Media dissemination

Twitter, Facebook, rimoftheworld.net Multinetwork messaging Towards a Unified Warning Model and System

Implementation Standards, Multihazard warning

Testing and Deployment Partnerships, Pilot Studies

Training

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BACKUPS

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Organization PolicySpecifications

•Who will receive the notifications?

•What modalities will be used?

•School Principal:

•Receives updates

•Makes decisions

•Communicates decision to others

•All Staff

•Receives messages

CrisisAlert – A Meta Alerting System for Organizations

Crisis PolicySpecifications

Crisis Alert

•Which messages to send?

•Who should receive them?

•Personalization and Customization

Crisis Information from Emergency Operations Center

Automatic notification systems (USGS, EDIS, CAP based systems. ..)

Proprietary delivery mechanism used by the organization/school

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Implementation on Mobile Devices

Maemo

Spatial Dissemination

RADcast

Flash Broadcast

People close to the epicenterDetailed map of the damages

Location of sheltersPeople close to chemical facilities

Map of the damaged area, Location of the dangerous

chemical facilitiesInformation about the chemical

People in safe areasHospital information

General information about the emergency

Short & Long Term Warning

Part of the Disaster Portal Project: in use by the City of Ontario

Earthquake ScenarioEarthquake Scenario

Timeline

Shakecast Information

Detailed Information

Earthquake Early Warning

Visual and sound notifications of

“Duck and Cover”

Earthquake hits the area

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Map of the affected areaGeneric first-aid information