MANET WG Overview - Internet Engineering Task Force · PDF file• RFC 7188 (OLSRv2/NHDP updates on TLV processing) • RFC 7367 (SMF MIB) ... Select 1-hop Nbr providing only path

MANETWGOverview96thIETFBerlin2016

ManetWGChairs

WhatisMANET?•  MobileAdhocNetwork

–  Thevision:tosupportrobustandefficientoperaGoninmobilewirelessnetworksbyincorporaGngIProuGngfuncGonalityintomobilenodes.

– MayoperateinisolaGon,ormayhavegatewaystoandinterfacewithafixednetwork.

•  KeyFeaturesofaMANETnetwork–  Dynamictopologies–  Bandwidth-constrainedwirelesslinks–  Energy-constrainedoperaGon–  Limitedphysicalsecurity– Wirelessinterfaces

Wiredvs.WirelessOverview

Traditional Network characteristics

Networks are based on high-speed links, with very low transmission error rates

Topology changes are relatively rare, and typically planned events

Strict hierarchical design is easy to enforce

Ad-hoc Network characteristics Low bandwidth, variable

speed links Packet loss rates of 50%

are common Rapid topology changes

makes strict hierarchy impossible

Network must function in harsh environmental conditions

RadioTypes

Radio types •  Point-to-Point – These radios typically use

TDMA; some also employ highly directional beams.

•  Appear to a router as a single point-to-point link, or a collection of point-to-point links

•  Use directional beams for better transmission length, and lower probability of detection/interception

•  Broadcast/multicast traffic must be replicated for physical transmission on all radio links

Radio types continued

•  Broadcast, Multi-Access radios •  At OSI Layer 2, these radios employ MAC

protocols that are similar to Ethernet (e.g. 802.11)

•  Base use case is omni-directional, broadcast/multicast transmission is accomplished with a single physical send.

Addressing

Wired Network Topology

10.3.3.x 10.3.2.x 10.3.1.x

Wireless addressing

12.10.80.0 14.22.60.0 22.40.31.0

Subnetting Doesn’t Work!!! (at least not well)

Other Addressing Issues

•  Standard methods for auto-assigning non-duplicate addresses in a MANET do not exist

•  Reacquiring addresses based on motion or location disrupts applications and causes security issues

IETFMANETDocumentsRFCs

•  RFC2501(issuesandconsideraGons)•  RFC3561(AODV)•  RFC3626(OLSR)•  RFC3684(TBRPF)•  RFC4728(DSR)•  RFC5148(Jiaer)•  RFC5444(PacketBuildingBlock)•  RFC5497(Gmetlv)•  RFC5498(IANAAllocaGons)•  RFC6130(NHDP)•  RFC6621(SMF)•  RFC6622(packetbbintegritycheck)•  RFC6779(NHDPMIB)•  RFC7181(OLSRv2)•  RFC7182(updatedpacketbbintegritycheck)•  RFC7183(OLSRv2useofsec)•  RFC7184(OLSRv2MIB)•  RFC7185(OLSRv2metricraGonal)•  RFC7186(NHDPsecthreats)•  RFC7187(OLSRv2opGmizaGon)•  RFC7188(OLSRv2/NHDPupdatesonTLVprocessing)•  RFC7367(SMFMIB)•  RFC7466(NHDPopGmizaGon)•  RFC7631(TLVnaming)•  RFC7722(OLSRv2mulGtopology)•  RFC7779(DATmetric)•  RFC7859(idenGybasedsignatures)

InthePipe•  SecurityThreatsforSimplifiedMulGcastForwarding(SMF)•  NHDPMIB•  RFC5444Usage•  OLSRv2secthreats•  OLSRv2mulGpath•  DynamicLinkExchangeProtocol•  CreditwindowextensionforDLEP

Dead•  AODVv2

Neartermdeliverables•  ManetManagementanddeployment•  DLEPextenGons•  MulGcastForwardingInformaGonBase

FirstGeneraGonExperimentalProtocols

MANETBriefHistoryMANETStart~1997-2007• 2ExperimentalProacGveProtocols

• 2ExpReacGve

MANETReboot2005-2016• 1standardProacGve• 1standardReacGve

BuildingBlockApproach2006-2011• Packetformat• Neighbordiscovery• Protocols• GeneralizedmulGcast

Today2010-current•  Radio/RouterInterface•  MulGcastbuildingblock

approach

Extensions2007-current•  Time•  Security•  ProtocolImprovements

SecThreats(atAD)

SecThreats(InIESG)

SecThreats(RFC7183)

MIB(RFC6779)

MIB(RFC7367)

MANETIANA(RFC5498)

PacketBB(RFC5444)

TimeTLV(RFC5497)

NHDP(RFC6130)

SMF(RFC6121)

MIB(RFC7184)

OLSRv2(RFC7181)

Jiaer(RFC5148)

PacketBBSec(RFC7182)

PacketIBS(RFC7859)

IETFMANETDocumentStructureOverview

IntCheck(RFC7183)

DATmetric(RFC7779)

MulGTopo(RFC7722)

NHDPOpt(RFC7466)

DLEP(WGLCfinished)

PacketBuildingBlock(Packetbb)RFC5444Overview

WhatisPacketbb?RFC5444

•  PacketBuildingBlock–  apacketformatdesignedforcarryingmulGplerouGngprotocolmessagesforinformaGonexchangebetweenMANETrouters

•  KeyFeaturesofPacketbb–  MulGplemessagesperpacket–  ExtensibleviaTypeLengthValuefields

•  PacketTLV•  MessageTLV•  AddressTLV

–  Compression•  Addresscompression•  TLVcompression

–  MulGplexerformulGprotocoloperaGon

Packet

Pkt-headr

Version

Pkt-flags

Pkt-seq-num?

Tlv-block?

Tlvs-length

Tlv*

Tlv-type

Tlv-flags

Tlv-type-ext?

Index-start

Index-stop?

Length

Value?

Message*

Msg-header

Msg-type

Msg-flags

Msg-addr-length

Msg-size

Msg-orig-addr?

Msg-hop-lim

it?

Msg-hop-count?

Msg-seq-num

?

Tlv-block

Tlvs-length

Tlv*

Tlv-type

Tlv-flags

Tlv-type-ext?

Index-start

Index-stop?

Length

Value?

Addr-block*

Num

-addr

Addr-flags

Head-length

Head?

Tail-length

Tail?

Mid*

Prefix-length*

Tlv-block*

Tlvs-length

Tlv*

Tlv-type

Tlv-flags

Tlv-type-ext?

Index-start

Index-stop?

Length

Value?

PacketBuildingBlock(RFC5444)Structure

2/14/2011 18NavalResearchLab

Packet

Pkt-headr

… Tlv-block

… Pkt-Tlv

Tlv-type

…

Value

Message

Msg-header

Msg-type

…

Tlv-block

… Msg-Tlv

Tlv-type

…

Value

Addr-block…

Tlv-block

… Addr-Tlv

Tlv-type

…

ValuePacketBuildingBlock(RFC5444)Usage

2/14/2011 19NavalResearchLab

PacketBuildingBlockRFC5444

,------------------

|PACKET|------------------|*Packetversion:0|*Packetflags:0|,-------------------||MESSAGE||-------------------||*Messagetype:7||*Messageaddr.length:4||*Messageflags:0|`-------------------|`------------------

• SimpleExample

01234567890123456789012345678901+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|00000000|Msgtype=7|00000011|Leng|+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|th=6|TlvBlockLength=0|+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

NeighborhoodDiscoveryProtocol(NHDP)RFC6130Overview

WhatisNeighborhoodDiscoveryProtocol(NHDP/RFC6130)?

•  NeighborhoodDiscoveryProtocol–  UseslocalexchangeofHELLOmessagessothateachroutercan

determinethepresenceof,andconnecGvityto,its1-hopandsymmetric2-hopneighbors

•  KeyFeaturesofNHDP–  UsesRFC5444

•  Extendable•  CanusecommonlydefinedTLVs

–  Hellobaseddiscovery•  DiscoversoneandtwohopneighborinformaGon•  DiscoversSymmetry•  Supportsmetrics•  DynamicGmers

–  ProvidesinformaGonbasesforuseofotherprotocols–  MulGpleinterfacesupport

A B C

1 2 3

1 2 3

NHDPExample1StandardSingleInterfaceTopology

PhysicalNetworkTopology NHDPRepresentaGon

A B C

1 2,4 3

1 2,4 3

NHDPExample2DualAddressedIfaceon1-HopNeighbor


A B C

1 2 3,4

1 23

4

NHDPExample3DualAddressedIfaceon2-HopNeighbor


A B C

1,5 2,6 3,4

1,5 2,63

4

NHDPExample4DualAddressedInterfaces


A B C

1 2 3

4

1 2 3

4

NHDPExample5DualInterfaceon2-HopNeighbor


A B C

1 2

5 4

1 2

5 4

NHDPExample6Dualinterfaceon1-HopNeighbor


A B C

1 2 3

5 4

1 2

5

3

4

NHDPExample7DualIfaceon1-Hopand2-HopNeighbors


A B C

1 2 3

6 5

1 2

5

3

6

2

5

3

NHDPExample8DualIfaceLocallyandon1-HopNeighbor

PhysicalNetworkTopology

NHDPRepresentaGon

A B C

1 2 3

6 5 4

1 2

5

3

4

6

2

5

3

4

NHDPExample9DualInterfaceonAllRouters


NHDPRepresentaGon

A B C

1,2 5,6 9,10

3,4 7,8 11,12

1,2 5,6

7,8

9

10

12

11

3,4

5,6

7,8

9

10

12

11

NHDPExample1DualAddressedDualIfacesonAllRouters


NHDPRepresentaGon

SimplifiedMulGcastForwarding(SMF)RFC6621CDSElecGonOverview

WhatisSMF?•  SimplifiedMulGcastForwarding

–  providesbasicIPmulGcastforwardingsuitableforMANETuse

•  KeyFeatures– DuplicatepacketdetecGon

•  IPheaderdupID•  Hashbased

– NetworkwidedisseminaGon–  ReducedforwardingviaconnecteddominaGngset(CDS)algorithms

– GatewaytotradiGonalInternetIPmulGcast

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SMFCDSalgorithmsillustraGon:• ECDS• S-MPR• MPR-CDS

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Requirements:• 2-hopneighborinformaGon• UniquerouterpriorityselngsFeatures:• SinglesharedCDSforallrouters• SelfelecGon• SimplesupportforclassicforwardersAlgorithm1.  Ifleafnodethen,doNOTforward2.  Ifpriority>all1-hopand2-hopneighbors,

forward3.  StarGngwithgreatestpriority1-hop

neighborvisitneighbors1.  Addneighborsvisitedwith>priority

thanlocaltoqueue2.  Popqueue,visititsneighbors

4.  Ifany1-hopneighborunvisited,forward

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ECDSRequirements• 2-hopneighborinformaGon• UniquerouterpriorityECDSAlgorithm1.  Ifleafnodethen,doNOT

forward2.  Ifpriority>all1-hopand2-

hopneighbors,forward3.  StarGngwithgreatest

priority1-hopneighborvisititsneighbors1.  Addneighbors

visitedwith>prioritythanlocaltoqueue

2.  Popqueue,visititsneighbors

1.  Ifany1-hopneighborunvisited,forward

UseRouterIDsforthisexampleExamplefrom1Notaleafnode,

nextstep

1isnot>allneighbors,next

step

13isunvisitedso1willforward

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ResultantCDS

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Requirements:• 2-hopneighborinformaGon• PrevioushopinformaGonrequired• MethodtoinformneighborsofMPRstatusFeatures:• Sourcespecificfloodingpaths• Electedbyneighbors• ShortesthoppathsusedAlgorithm1.  Eachrouterselects,asitsMPRs,asubset

of1-hopneighborswhichcoverall2-hopneighbors

2.  RoutersinformneighborsofMRPstatus3.  TrafficfirstreceivedfromanMPRselector

isforwardedotherwiseblocked

Examplefrom1

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S-MPRRequirements• 2-hopneighborinformaGon• PrevioushopinformaGon• MethodtoinformNbrsofMPRsS-MPRAlgorithm1.  SelectMPRs

1.  Select1-hopNbrprovidingonlypathto2-hopNbr

2.  Select1-hopNbrwhichwouldcovermostcoverednodes

2.  InformneighborsofMPRstatus

3.  TrafficfirstreceivedfromanMPRselectorisforwarded

4.  Trafficfirstreceivedfromanon-MPRselectisblocked

No2-hopNbrslentocover

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ResultantMPRelecGon

NoGcethat15doesnotforward

SamplefloodstarGngfrom4

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ResultantCDS(whenstarGng

from4!)11

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Requirements:• 2-hopneighborinformaGon• MethodtoinformneighborsofMPRstatus• UniquerouterpriorityselngsFeatures:• SinglesharedCDSforallroutersAlgorithm1.  MPRelecGonisperformedandsharedin

thesamewayasS-MPR2.  Routerswhichhavebeenselectedasan

MPRbyanyotherrouterforwardif1.  ithaslargerprioritythanallofits1-

hopneighbors2.  the1-hopneighborwiththelargest

priorityhasselecteditasanMPR

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MPR-CDSRequirements• 2-hopneighborinformaGon• MethodtoinformNbrsofMPRs• UniquerouterpriorityselngsMPR-CDSAlgorithm1.  MPRelecGonisperformed

andsharedinthesamewayasS-MPR

2.  RouterswhichhavebeenselectedasanMPRbyanyotherrouterforwardif1.  ithaslargerpriority

thanallofits1-hopneighbors

2.  the1-hopneighborwiththelargestpriorityhasselecteditasanMPR

Examplefrom1

Doesnothavelargestpriority15hasselectedusasitsMPR

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ResultantCDS 11

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OpGmizedLinkStateRouGngProtocolv2RFC7181Overview

WhatisOLSRv2?•  OpGmizedLinkStateRouGngProtocolv2

–  AproacGveunicastrouGngprotocolforuseinMANETnetworks.

•  KeyFeatures–  UsesNHDP

•  UsestwohopinformaGon•  AugmentsNHDPhellomessageswithOLSRv2specificTLVs

–  MetricSupport–  UseofmulG-pointrelayfordisseminaGngnetworktopologyusingreducedforwardingset

–  Supportsaaachednetworks–  Providesshortestpathroutes–  DynamicTimers

What’sOpGmizedaboutOLSRv2?•  ReducednumberofrouterssourcingTCmessages

–  OnlyroutersselectedasMPRsourceTCmessages•  ReducedadverGsedaddressincludedintopologycontrol(TC)messages–  OnlyMPRselectorsareadverGsed

•  ReducGonofforwardedTCmessagesusingMPRelecGon–  OnlyMPRneighborsrebroadcastTCmessages.

•  Dynamic+distancebasedGmers–  allowdynamicallyslowerupdaterates–  allowlimitedfloodingofTCmessages(e.g.fisheyeorhazyflooding)

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Reduced#ofSourcesforTCmessages

Reduced#ofAdverGsed

neighborsinTCmessages

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Reduced#ofForwardersforTC

messages

Forwarderswhenwhen

starGngfrom4

ManetDaemon

•  GraphState

NHDPInstance

OLSRv2Instance

SMFInstance

NHDPInstance

SMFInstance

NHDPInstance

OLSRv2InstanceOLSRMI

NHDPMI

SMFMI

IF0

IF1

IFN

Mult-cast

Mult-cast

Mult-cast

ManetInterfaceMux(IfN)

ManetInterfaceMux(IF0)

ManetInterfaceMux(IF1)

PacketBBClassMessages

RawPacketBBPackets

SMFChannel

ControlChannel

SMFForw

arding

Engine

SMFController

DynamicLinkExchangeProtocolOverview

WhatisDLEP?

•  DynamicLinkExchangeProtocol•  KeyFeatures

– AllowsradiostoindicatethecharacterisGcsofvariable-qualityRFlinksastheychange

– Routerscanaskradioforspecificdatarateordelay

•  DLEPspecifies“what”dataitemsgetexchanged–NOT“how”thoseitemsareused

What is DLEP (continued) •  MANETs need to handle rapid mobility profiles

–  Both in terms of topology changes, and devices entering and leaving the network due to mobility

•  In these environments, relying solely on ‘HELLO’ and ‘DEAD’ timers running at Layer 3 can be problematic

•  And all the while, the link quality (speed, delay) can and does change

•  Routers and radios must be able to signal each other in order for route tables to converge quickly –  Convergence events are necessary to minimize black-

holes and routing loops –  Link metrics are needed to advertize the robustness of

the path

What is DLEP (last slide - I promise)

•  DLEP is specified as a 1-hop ONLY protocol –  Multicast discovery ‘signals’ are sent/received with

TTL=1 •  TCP session employs the Generalized TTL

Security Mechanism (GTSM – RFC 5082) •  ALL specified messages are designed to be

exchanged between a radio and its LOCALLY ATTACHED routers –  NO Over-The-Air (OTA) messaging is specified –  However, some proprietary OTA signaling between

modems and/or modem-to-hub is implicit

DLEP using multiple radios Routers can use radio feedback to monitor link status and find the best wireless paths through complex networks

JTRS Satellite Link

TTNT

CDL

§  Op0mizesIProu0ngoverradionetworks

§  Immediatelyrecognizesandadaptstonetworkchanges

§  Easilyroutesbetweenline-of-sightandnon-line-of-sightlinks