Internet Connectivity Sharing inInternet Connectivity Sharing

Internet Connectivity Sharing inInternet Connectivity Sharing inInternet Connectivity Sharing in Internet Connectivity Sharing in MultiMulti--path Spontaneous Networks: path Spontaneous Networks:

C i d I t ti N t kC i d I t ti N t kComparing and Integrating NetworkComparing and Integrating Network--and Applicationand Application--Layer ApproachesLayer Approaches

Paolo BellavistaCarlo GiannelliCarlo Giannelli

1.7.2010 - Mobilware'10DEIS, Università degli Studi di Bologna,

Viale Risorgimento, 2 - 40136 Bologna [email protected]

AgendaAgenda

Spontaneous networkingSpontaneous networkingopportunities and technical challenges

Internet connectivity sharingInternet connectivity sharingmulti-hop, multi-path, heterogeneous, opportunisticopportunisticlayer-3 vs. layer-7 approaches

RAMP middlewareRAMP middlewarelayered architecture

i iddl f iliti f ti dprimary middleware facilities for supporting and facilitating app developmentpreliminary experimental results

Chicago, USA — 1.7.2010 Paolo Bellavista - Mobilware '10

preliminary experimental results

1/18

SpontaneousSpontaneous NetworkingNetworking (1)(1)gg ( )( )

Impromptu interconnection of mobile and fixed nodesilli t h t t dusers willing to share content and resources

Maximize resource/service utilization by potentially interconnected nodes

heterogeneous wireless technologiesboth infrastructure and ad-hoc connectivitymultiple connectivity opportunities


multiple connectivity opportunitiessporadic/opportunistic Internet connectivity

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Spontaneous Networking (2)Spontaneous Networking (2)Node cooperation to

id i l h ti it

UMTS Base Station

IEEE 802.11Access Point

provide single-hop connectivitymanage multi-hop connectivitysupport peer-to-peer services

CDA

E

IEEE 802.11IBSS

BluetoothPi tsupport peer to peer services

FB G

interface providing ad hoc connectivity

Piconet

Bluetooth Piconet

IEEE 802.11IBSS

l h l k

Peer-to-peer resource sharing (Internet connectivity file sharing )

single‐hop link

(Internet connectivity, file sharing, …)service advertising: NodeA provides lesson notesservice discovery: NodeF looks for nodes that share filesservice invocation: NodeF browses and downloads notes stored on NodeA

NodeA and NodeF may reside in different layer 3


NodeA and NodeF may reside in different layer-3 networks

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Spontaneous Networking:Spontaneous Networking:Technical ChallengesTechnical ChallengesTechnical ChallengesTechnical Challenges

Heterogeneous nodes and connectivityIEEE 802 11 Bl t th Eth tIEEE 802.11, Bluetooth, Ethernetseveral operating systems

Decentralized and loosely-coupled networkDecentralized and loosely-coupled network management

localized provisioning of layer-2/3 connectivityinterconnection of heterogeneous layer-3 networks

Erratic and unpredictable behaviord b l /d i f knodes abruptly create/destroy pieces of network

nodes dynamically join/move/leave

Scenario and management complexity makes hard the development of novel applications from


hard the development of novel applications from scratch => need for middleware solutions

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RAMP: Real AdRAMP: Real Ad--hoc hoc MultiMulti--hop Peerhop Peer--toto--peerpeerMultiMulti hop Peerhop Peer toto peerpeer

Easy-to-use middleware supporting spontaneous network management transparent in relation tonetwork management, transparent in relation to

operating systemswireless technologieslayer-3 network configurationsnode mobility

Unicast and broadcast comm. supportper-packet sendUnicast, sendBroadcast, p p , ,receive

Peer-to-peer service provisioning and discoveryi i i fi d iper-service registerService, findService

RAMP Java prototype available on MS Windows


RAMP Java prototype available on MS Windows XP/Vista/7, Linux, and Mac OS X

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RAMP RAMP Layered ArchitectureLayered ArchitectureLayered ArchitectureLayered Architecture

Service Layerhigh-level features for

sendUnicastsendBroadcastreceive

S i

registerServicefindServices

gpeer-to-peer service offering and discoveryDiscovery: mission-oriented E2E Comm

ServiceLayer

localservices

ServiceManager

Discovery

Discovery: mission orientedTTL-bound broadcastServiceManager: registration and advertising

CoreLayer

Dispatcher Listener XHeartbeater

E2E Comm

and advertisingservice invocation via Core Layer

Core LayerCore Layerlow-level primitives for end-to-end communicationE2EComm: communication primitives for data en/decapsulation into RAMP packetsRAMP packetsHeartbeater for local IP addresses gathering and single-hop neighbors discoveryDispatcher: actual inter-node packet forwarding


Dispatcher: actual inter-node packet forwardinglistener-based plug-in for run-time packet management

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Internet Connectivity SharingInternet Connectivity Sharingin Spontaneous Networksin Spontaneous Networksin Spontaneous Networksin Spontaneous Networks

Border Nodes (BNs) with di t I t t ti itdirect Internet connectivity share their access UMTS

Base StationIEEE 802.11Access Point

Layer-3 (L3) approachoperating system default

t t t lti hC

DAIEEE 802.11

IBSSgateway to create multi-hop pathsat most one path for each

dF

B

E

G

BluetoothPiconet

nodeLayer-7 (L7) approach

packets managed and interface providing d h ti it

default gateway

Bluetooth Piconet

IEEE 802.11IBSS

L3 multi‐hop path

single‐hop link

packets managed and dispatched by RAMPsimultaneous exploitation of different paths and

ad hoc connectivityL3 multi‐hop path


different paths and different access

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Guidelines for InternetGuidelines for InternetConnectivity SharingConnectivity SharingConnectivity SharingConnectivity Sharing

L3 and L7 approaches togetherL3: minimum routing and communication overhead but localL3: minimum routing and communication overhead, but local decisions may affect remote nodesL7: multi-path enabling and operating system transparent, but increased communication overheadincreased communication overheadmultiple modes of combining L3 and L7 approaches

Context aware path selection (see also MMHC)Context-aware path selection (see also MMHC)quantitative metric for dynamic path evaluationlimited information dissemination to minimize overhead

Differentiated metrics at service initialization and provisioning timeprovisioning time

first, coarse-grained evaluation based on rather static context informationthen finer grained dynamic re evaluation based on context


then, finer-grained dynamic re-evaluation based on context related to actual run-time performance

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Internet Internet ConnectivityConnectivity SharingSharing::ApplicationApplication ComponentsComponentsApplicationApplication ComponentsComponents

InternetServiceBNs directly connected to the InternetregisterService to advertise Internet connectivity provisioningprovisioning

InternetClientInternetClientRAMP node requiring Internet connectivityfindService to discover BNs providing connectivity

Layer3Managerlayer-3 gateway modification Dispatcher listener monitoring traversing packets on intermediary nodes


intermediary nodes

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L3SP Mode:L3SP Mode:LayerLayer--3 Single Path3 Single PathLayerLayer 3 Single Path3 Single Path

BN1 X Y CIEEE 802.11Access Point single hop link1

BNUMTS

Access Point

default gateway

L3multi hop path

single‐hop link

C ll b ti f i t di d

BN2Base StationL3 multi‐hop path

Collaboration of intermediary nodesrequest forwarding from client to BNd i difi ti f l l d f lt tdynamic modification of local default gateway

Layer3ManagerLayer3Managermonitor traversing packets and recognize modification requests


qe.g., in Linux route and iptables commands

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L7MP Mode:L7MP Mode:LayerLayer--7 Multi Path7 Multi PathLayerLayer 7 Multi Path7 Multi Path

BN1 X Y CIEEE 802.11Access Point

single‐hop link1

UMTS

Access Pointdefault gateway

L7 multi‐hop path

Data to/from the Internet encapsulated into RAMP

BN2Base Station

ppackets at app layer and forwarded via DispatcherDouble proxy architetcure

I t tCli t/S i t iInternetClient/Service act as proxiese.g., HTTP proxy server on clients and BNs, en/decapsulating HTTP requests and responses

Multi-path connectivityincreased overall bandwidth


increased overall bandwidthgreater reliability

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L3L7CMP Mode:L3L7CMP Mode:L3 L7 Combo Multi PathL3 L7 Combo Multi PathL3 L7 Combo Multi PathL3 L7 Combo Multi Path

IEEE 802 11 single hop linkBN1 X Y CIEEE 802.11Access Point

default gateway

L3multi hop path

single‐hop link

BN2UMTS

Base Station

L3 multi‐hop path

L7 multi‐hop path

Both L3 and L7 approachesInternetClient selects the most proper mode atInternetClient selects the most proper mode at runtime

one L3 path + multiple L7 pathsp p pdouble-proxy in case of L7 approachsingle-proxy in case of L3 approach (no InternetService)

Chicago, USA — 1.7.2010 Paolo Bellavista - Mobilware '10 12/18

L3SP, L7MP, and L3L7CMP:L3SP, L7MP, and L3L7CMP:a Comparisona Comparisona Comparisona Comparison

L3SP modeprovides direct access to the Internet with no additionalprovides direct access to the Internet with no additional overheadbut path modification requests may affect other nodes

L7MP modeno need of path pre-configurationp p gbut double-proxy en/decapsulation overhead (only HTTP at the moment)

InternetBNX

L3L7CMP modesuitable for dynamic

i t ( L7MP)

Client node

Internet Client

Path L7

Internet Service

L7

L7cation

multi BNY net

environments (as L7MP)reduced overhead(in case of single-proxy)

Selector L3

L3

App

lic path

singlepath

Internet Service

L7

Y

Intern


(in case of single-proxy) BNZ

OS

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Dynamic Path SelectionDynamic Path Selection

Context-aware performance monitoring/evaluation and selection of available pathsp

dynamic weight-based exploitation of every BNstatic and dynamic metrics

PathLengthPathLengthstatic comparison of path length

PathThroughputwBN1=0.40wBN2=0.60

wBN1=0.33wBN2=0.67

wBN1=0.67wBN2=0.33at oug put

lightweight throughput monitoring BN1 X Y C

dynamic weight reconfigurationBN2

Chicago, USA — 1.7.2010 Paolo Bellavista - Mobilware '10 14/18

L7MP PerformanceL7MP PerformanceGoogle maps browsing: HTTP intensive communicationcommunication

very frequent interactions with limited payload size

B d idth li it ti t d BNBandwidth limitation towards BNsperiodic weights re-evaluation accordingly to really achieved throughputachieved throughputbandwidth allocation swap after 105s Internet

BN

C

BN1

X

125 (25) KB/s

( ) /BN2

25 (125) KB/s


Internet

BN1 BN215/18

L3L7CMP L3L7CMP PerfomancePerfomanceSame bandwidth allocation, both L3 and L7 approaches simultaneouslypp y

L3 path towards BN1, L7 path towards BN2throughputs are similar, L3 path slightly betterL7 h i h d b li h l l I t tL7 path weight tend to be slightly lower

Approach swap after 125sweights change accordingly after few iterations

Internet

BN1weights change accordingly after few iterationsC

BN1

X

30 KB/s

30 KB/BN2

30 KB/s

Internet


BN1 BN216/18

Conclusions andConclusions andOngoing WorkOngoing WorkOngoing WorkOngoing Work

RAMP supports multi-hop service-oriented communication in heterogeneous spontaneouscommunication in heterogeneous spontaneous networks

easy-to-use API for service development by non-expert programmers

Internet-connectivity sharing as possible central applicationapplication

layer-3 and layer-7 approaches simultaneouslymulti-path for greater quality and reliability

th d i l ti d l tiproper path dynamic evaluation and selection

Ongoing workOngoing worklive multimedia stream via DVB-T re-castingporting to additional mobile platforms, e.g., Google Android

d iPh OS


and iPhoneOS

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Any Questions?Any Questions?

Thanks for your attention ☺yQuestions time…

Prototype code and implementation insightshttp://lia.deis.unibo.it/research/RAMP/


http://lia.deis.unibo.it/Staff/PaoloBellavista/

18/18

Documents

Internet Connectivity Sharing inInternet Connectivity Sharing