1Copyright © 2000, Juniper Networks, Inc.

Packets & Photons: The Emerging Two

Layer Network

October 2001October 2001

2

Agenda

History of IP BackbonesHistory of IP Backbones

The Emerging Two Layer NetworkThe Emerging Two Layer Network

Network PlatformsNetwork Platforms

Standards and ForumsStandards and Forums

GMPLSGMPLS

3

Typical IP Backbone (Late 1990’s)

Data piggybacked over traditional voice/TDM transportData piggybacked over traditional voice/TDM transport

SONET/SDHDCS

SONET/SDHDCS

CoreRouter

ATMSwitch

MUX

SONET/SDHADM

CoreRouter

ATMSwitch

MUX

CoreRouter

ATMSwitch

MUX

CoreRouter

ATMSwitch

MUX

SONET/SDHADM

SONET/SDHADM

SONET/SDHADM

4

Why So Many Layers?

RouterRouter Packet switchingPacket switching Multiplexing and statistical Multiplexing and statistical

gaingain Any-to-any connectionsAny-to-any connections Restoration (several Restoration (several

seconds)seconds) ATM/Frame switchesATM/Frame switches

Hardware forwardingHardware forwarding Traffic engineeringTraffic engineering Restoration (sub-second)Restoration (sub-second)

MUXMUX Speed match router/ Speed match router/

switch interfaces to switch interfaces to transmission networktransmission network

SONET/SDHSONET/SDH Time division Time division

multiplexing (TDM)multiplexing (TDM) Fault isolationFault isolation Restoration Restoration

(50mSeconds)(50mSeconds) DWDMDWDM

Raw bandwidthRaw bandwidth Defer new constructionDefer new construction

ResultResult More vendor integrationMore vendor integration Multiple NM SystemsMultiple NM Systems Increased capital and operational costsIncreased capital and operational costs

5

SONET/SDH

DWDM

CoreRouter(IP/MPLS)

IP Backbone Evolution

MUX becomes MUX becomes redundantredundant

IP trunk requirements IP trunk requirements reach SDH aggregate reach SDH aggregate levelslevels

Next generation Next generation routers include high routers include high speed SONET/SDH speed SONET/SDH interfaces interfaces

CoreRouter(IP/MPLS)

MUX

SONET/SDH

DWDM(Maybe)

FR/ATM Switch

6

SONET/SDH

DWDM

CoreRouter(IP/MPLS)

IP Backbone Evolution

Removal of ATM Removal of ATM LayerLayer

Next generation Next generation routers provide trunk routers provide trunk speedsspeeds

Multi-protocol Label Multi-protocol Label Switching (MPLS) on Switching (MPLS) on routers provides routers provides traffic engineeringtraffic engineering

CoreRouter(IP/MPLS)

MUX

SONET/SDH

DWDM(Maybe)

FR/ATM Switch

7

Removing the ATM Layer

Why Remove ATM?Why Remove ATM? Two networks to manage - IP and ATMTwo networks to manage - IP and ATM Cell tax Cell tax Lack of high-speed SAR interfacesLack of high-speed SAR interfaces High density of virtual circuitsHigh density of virtual circuits IP routing protocol stressIP routing protocol stress

Logical Topology

8

Agenda

History of IP BackbonesHistory of IP Backbones

The Emerging Two Layer NetworkThe Emerging Two Layer Network

Network PlatformsNetwork Platforms

Standards and ForumsStandards and Forums

GMPLSGMPLS

9

Collapsing Into Two Layers

Optical Transport(OXCs, WDMs, SONET ?)

Optical Core

IP Service (Routers)

10

Collapsing Into Two Layers

IP router layer functionsIP router layer functions Service creationService creation Multiplexing and statistical gainMultiplexing and statistical gain Any-to-any connectionsAny-to-any connections Traffic engineeringTraffic engineering Restoration (10s ms)Restoration (10s ms) Subscriber to transport speed matchingSubscriber to transport speed matching Delay bandwidth buffering and congestion controlDelay bandwidth buffering and congestion control Internet scalabilityInternet scalability

Optical Transport(OXCs, WDMs, SONET ?)

Optical Core

IP Service (Routers)

11

Collapsing Into Two Layers

Optical transport layer functionsOptical transport layer functions TDM and standard framing formatTDM and standard framing format Fault isolation and sectioningFault isolation and sectioning Restoration (10’s ms)Restoration (10’s ms) SurvivabilitySurvivability Cost efficient transport of massive bandwidth (DWDM)Cost efficient transport of massive bandwidth (DWDM) Long haul transmission distancesLong haul transmission distances Metro transmission distances ????Metro transmission distances ????

Optical Transport(OXCs, WDMs, SONET ?)

Optical Core

IP Service (Routers)

12

The Emerging Two-Layer Network

Data Layer

Transport Layer

Routers

OXC’s

WDM’sLH Transport

TDM’s

IP Services

Reduced costReduced cost Transport layer visible to IP Transport layer visible to IP

ServicesServices Transport layer signaling is Transport layer signaling is

an open standard (RSVP & an open standard (RSVP & CR-LDP)CR-LDP)

Reduced complexityReduced complexity Network more scalableNetwork more scalable Uniform admin & Uniform admin &

management of IP and management of IP and transport layerstransport layers

13

Agenda

History of IP BackbonesHistory of IP Backbones

The Emerging Two Layer NetworkThe Emerging Two Layer Network

Network PlatformsNetwork Platforms

Standards and ForumsStandards and Forums

GMPLSGMPLS

14

SONET/SDH Benefits

Rapid and predictable restorationRapid and predictable restoration 10s of ms; depends on ring size10s of ms; depends on ring size Simple to engineerSimple to engineer

Standard framing and multiplexing Standard framing and multiplexing (Time Division Multiplexing [TDM])(Time Division Multiplexing [TDM])

MaintainabilityMaintainability Performance monitoringPerformance monitoring Fault isolation and sectioningFault isolation and sectioning Bandwidth managementBandwidth management Network managementNetwork management

TransparencyTransparency Voice, video or data trafficVoice, video or data traffic

ChallengeChallenge Remove complexity Remove complexity

and keep benefitsand keep benefits

15

TrafficQuickly

ReroutedAfter Failure

SONET/SDH Benefits

Rapid and predictable restorationRapid and predictable restoration 10s of ms; depends on ring size10s of ms; depends on ring size Simple to engineerSimple to engineer

Standard framing and multiplexing Standard framing and multiplexing (Time Division Multiplexing [TDM])(Time Division Multiplexing [TDM])

MaintainabilityMaintainability Performance monitoringPerformance monitoring Fault isolation and sectioningFault isolation and sectioning Bandwidth managementBandwidth management Network managementNetwork management

TransparencyTransparency Voice, video or data trafficVoice, video or data traffic

ChallengeChallenge Remove complexity Remove complexity

and keep benefitsand keep benefits

16

SONET/SDH Limitations

Traditional SONET/SDH-based networksTraditional SONET/SDH-based networks Engineered for voice, not dataEngineered for voice, not data Slow to provisionSlow to provision

Planning complexityPlanning complexity Grooming complexityGrooming complexity Delivery measured in weeksDelivery measured in weeks

Expensive to scaleExpensive to scale Space, power, one wavelength per chassisSpace, power, one wavelength per chassis

InflexibleInflexible Static not dynamic bandwidthStatic not dynamic bandwidth Granularity – why not 5.5Gbps ?Granularity – why not 5.5Gbps ?

Little interoperability at “control plane”Little interoperability at “control plane” Customers forced to buy from one vendorCustomers forced to buy from one vendor Stifles “best-in-class” deploymentStifles “best-in-class” deployment

Packet layer – no visibility into optical layerPacket layer – no visibility into optical layer

17

What is an IP Router?

Minimum qualificationsMinimum qualifications Capable of switching IP datagrams: Capable of switching IP datagrams:

L3 forwardingL3 forwarding Symmetric any-port-to-any-port Symmetric any-port-to-any-port

switching speedswitching speed Delay-bandwidth buffering, Delay-bandwidth buffering,

plus congestion controlplus congestion control Internet scale IS-IS, OSPF, MPLS, BGP4Internet scale IS-IS, OSPF, MPLS, BGP4

Today’s benchmarkToday’s benchmark Wire-rate forwarding on all ports Wire-rate forwarding on all ports

for 40-byte packetsfor 40-byte packets Performance independent of loadPerformance independent of load Support of CoS queuing, shaping, Support of CoS queuing, shaping,

and policingand policing Traffic engineeringTraffic engineering Classification and filtering at wire rateClassification and filtering at wire rate

A Device Which Moves IP Datagrams Across

an Internetwork From Source to Destination

1 - Physical

2 - Datalink

4 - Transport

5 - Session

6 - Presentation

7 - Application

ISO 7 Layer Model

3 - Network3 - Network

18

What is an IP Router?

Optimal routesOptimal routes Calculate and select the best routes – Calculate and select the best routes –

many methodsmany methods SimplicitySimplicity

Functional efficiency with low routing Functional efficiency with low routing protocol overheadprotocol overhead

Robust and stableRobust and stable Predictable and correct functionality Predictable and correct functionality

in a variable environment (hardware in a variable environment (hardware failure, high load, topology changes)failure, high load, topology changes)

Rapid convergenceRapid convergence Slow route calculations cause loops Slow route calculations cause loops

and drops in serviceand drops in service FlexibilityFlexibility

Speed + accuracy to adapt to Speed + accuracy to adapt to network changes (bandwidth, delays, network changes (bandwidth, delays, queues, traffic levels, etc.)queues, traffic levels, etc.)

Routing Algorithm Goals

1 - Physical

2 - Datalink

4 - Transport

5 - Session

6 - Presentation

7 - Application

ISO 7 Layer Model

3 - Network3 - Network

19

What is an IP Router?

Any-to-any connectivityAny-to-any connectivity Internet scale routing allows anyone Internet scale routing allows anyone

to connect to anyone to connect to anyone (within or outside of own company)(within or outside of own company)

ApplicationsApplications Processing granularity to Processing granularity to

differentiate HTML from FTPdifferentiate HTML from FTP MulticastMulticast

Not possible with voice circuit Not possible with voice circuit switching technology switching technology

Internet radio, video on demand, Internet radio, video on demand, push Webpush Web

Content sitesContent sites Directing Web trafficDirecting Web traffic Complementing cache serversComplementing cache servers SecuritySecurity

IP Service Creation

1 - Physical

2 - Datalink

4 - Transport

5 - Session

6 - Presentation

7 - Application

ISO 7 Layer Model

3 - Network3 - Network

20

Optical Cross-connects (OEO)

DXC/DCS

SONET/SDHDigital Cross-connect (DXC) Also known as DigitalCross-connect Switch (DCS)

21

Optical Cross-connects (OEO)

DS-1 DS-3

ST

S-1

STS-N

AT

MD

S-3

STS-NATM STS-1

DS

-1

STS-N

ATM

DS

-1

DS-1

DS-3

ST

S-N

Electrical SwitchMatrix

SONET/SDHDigital Cross-connect (DXC) Also known as DigitalCross-connect Switch (DCS)

STS-N ATM DS-1 DS-3

22

All Optical Cross-connects (OOO)

OXC/PXC

All Optical Cross-connect (OXC) Also known as PhotonicCross-connect (PXC)

23

All Optical Cross-connects (OOO)

Optical SwitchFabric

3

2

2

4

4

1

1

3

All Optical Cross-connect (OXC) Also known as PhotonicCross-connect (PXC)

24

What is an OpticalCross-connect?

Connects one port (Connects one port () to ) to another portanother port

Add/Drop function with Add/Drop function with certain certain

Delivers high bandwidthDelivers high bandwidth Quick to provision bandwidthQuick to provision bandwidth

Port 3

Port 4

1

1

2

2

Port 2

Port 1

1 - Physical

2 - Datalink

4 - Transport

5 - Session

6 - Presentation

7 - Application

ISO 7 Layer Model

3 - Network

25

Reflector

MEMs tilting mirrors

Fibers

Imaging Lenses

OXC/PXC Switching Mechanisms

Micro-electrical Mechanical Micro-electrical Mechanical SystemsSystems

MEMsMEMs Used for many other applicationsUsed for many other applications

From Lucent, Corning, Xros From Lucent, Corning, Xros (Nortel), and others(Nortel), and others

Currently 8 x 8 OXC Currently 8 x 8 OXC 256 mirrors, long-term goal 1,024256 mirrors, long-term goal 1,024

OXCOXC ADM uses seesaw MEMSADM uses seesaw MEMS

Electrical controlsElectrical controls Voltage applied to mirror; tilts on Voltage applied to mirror; tilts on

2 axis + or – 6 degrees2 axis + or – 6 degrees

Switch times typically 10 to 25 msSwitch times typically 10 to 25 ms

26

OXC/PXC Switching Mechanisms

Liquid Crystal Light ValvesLiquid Crystal Light Valves From Spectra From Spectra

Switch and ChorumSwitch and Chorumtechnologiestechnologies

Switch speed Switch speed sub-millisecondsub-millisecond

Future switch Future switch speed in nanosecondspeed in nanosecond

1 x 2 port switch1 x 2 port switch 2 x 2 Add/Drop2 x 2 Add/Drop Electrical controlsElectrical controls

Input Output 1

Polarizing Beam

Splitter

ON

Liquid Crystal Cell

Polarizing Beam

Splitter

Liquid Crystal Cell

27

OXC/PXC Switching Mechanisms

Liquid Crystal Light ValvesLiquid Crystal Light Valves From Spectra From Spectra

Switch and ChorumSwitch and Chorumtechnologiestechnologies

Switch speed Switch speed sub-millisecondsub-millisecond

Future switch Future switch speed in nanosecondspeed in nanosecond

1 x 2 port switch1 x 2 port switch 2 x 2 Add/Drop2 x 2 Add/Drop Electrical controlsElectrical controls

Input

Output 2

Liquid Crystal Cell

Polarizing Beam

Splitter

Liquid Crystal CellOFF

Polarizing Beam

Splitter

28

OXC/PXC Switching Mechanisms

BubblesBubbles From AgilentFrom Agilent 32 x 32 or dual 16 x 32 ports32 x 32 or dual 16 x 32 ports Suitable forSuitable for

Wavelength Interchange Wavelength Interchange Cross-connect (WIXC)Cross-connect (WIXC)

Wavelength Selective Wavelength Selective Cross-connect (WSXC)Cross-connect (WSXC)

Optical Add/Drop Multiplexers Optical Add/Drop Multiplexers (OADM)(OADM)

Inkjet + Silica Planar Inkjet + Silica Planar Lightwave CircuitryLightwave Circuitry

Electrical controlsElectrical controls Bubbles created by heating Bubbles created by heating

“index matching fluid”“index matching fluid” Switch times under 10 msSwitch times under 10 ms

29

Developing an All OpticalPacket Router

NeedsNeeds How do you read a photonic header?How do you read a photonic header?

The “pipeline” approach?The “pipeline” approach? Switching and logicSwitching and logic

Current technology not fast enoughCurrent technology not fast enough Lithium Niobate devices have speed, Lithium Niobate devices have speed,

but too much crosstalkbut too much crosstalk Photonic Bandgap Devices Photonic Bandgap Devices

(optical equivalent to transistor)(optical equivalent to transistor) Buffering/MemoryBuffering/Memory

Optical buffers (fixed loop delays) exist, Optical buffers (fixed loop delays) exist, but are insufficientbut are insufficient

Bi-stable lasersBi-stable lasers Holographic memoriesHolographic memories SEEDS (Self Electro-optic Effect Devices)SEEDS (Self Electro-optic Effect Devices)

30

Agenda

History of IP BackbonesHistory of IP Backbones

The Emerging Two Layer NetworkThe Emerging Two Layer Network

Network PlatformsNetwork Platforms

Standards and ForumsStandards and Forums

GMPLSGMPLS

31

Operational Approaches:Overlay and Peer Models

Overlay modelOverlay model Two independent control planesTwo independent control planes

IP/MPLS routing IP/MPLS routing

Optical domain routingOptical domain routing

Router is client of optical domainRouter is client of optical domain

Optical topology invisible to routersOptical topology invisible to routers

Routing protocol stress – scaling issuesRouting protocol stress – scaling issues

Does this look familiar?Does this look familiar?

Peer modelPeer model Single integrated control planeSingle integrated control plane

Router and optical switches are peersRouter and optical switches are peers

Optical topology is visible to routersOptical topology is visible to routers

Similar to IP/MPLS modelSimilar to IP/MPLS model

?

32

Operational Approaches:The Hybrid Model

Hybrid modelHybrid model Combines peer & OverlayCombines peer & Overlay

Middle ground of 2 extremes Middle ground of 2 extremes

Benefits of both modelsBenefits of both models

Multi admin domain Multi admin domain support support

Derived from overlay Derived from overlay modelmodel

Multiple technologies Multiple technologies within domainwithin domain

Derived from peer modelDerived from peer model UNI

Peer

33

Standards and Industry Forums

Optical Internetworking Forum (OIF)Optical Internetworking Forum (OIF) Industry forumIndustry forum Kick-off meeting May 1998Kick-off meeting May 1998 Standard OIF UNI based Standard OIF UNI based

on IETF work (CR-LDP/RSVP)on IETF work (CR-LDP/RSVP)

Internet Engineering Task Force (IETF)Internet Engineering Task Force (IETF) Driving GMPLS standards developmentDriving GMPLS standards development

Initial application was MPlambdaSInitial application was MPlambdaS Peer model and Hybrid modelPeer model and Hybrid model Extend MPLS traffic engineering Extend MPLS traffic engineering

to the optical control planeto the optical control plane Rapid provisioningRapid provisioning Efficient restorationEfficient restoration

ITU-TITU-T Study Group 13Study Group 13 Study Group 15Study Group 15

34

IETF

GMPLS now Hosted by CCAMP WGGMPLS now Hosted by CCAMP WG Common Control And Measurement PlaneCommon Control And Measurement Plane

MPLS WG revised charter (without GMPLS)MPLS WG revised charter (without GMPLS) Eleven main GMPLS building blocksEleven main GMPLS building blocks

Internet DraftsInternet Drafts Current work includes extending existing control Current work includes extending existing control

protocols (example, OSPF & ISIS)protocols (example, OSPF & ISIS) New & future extensions consideredNew & future extensions considered

BGP4BGP4 For cross AS, and Carrier of Carriers applicationsFor cross AS, and Carrier of Carriers applications

LCASLCAS Link Capacity Adjustment Scheme protocol for SONETLink Capacity Adjustment Scheme protocol for SONET SONET Virtual Concatenation (dynamic TDM circuit control)SONET Virtual Concatenation (dynamic TDM circuit control)

Intent to submit work to ITU-TIntent to submit work to ITU-T

35

ITU-T

Study Group 13 (SG13)Study Group 13 (SG13) Focus: Multi-protocol & IP-based networks Focus: Multi-protocol & IP-based networks

& their inter-working& their inter-working Study Group 15 (SG15)Study Group 15 (SG15)

Focus: Optical & other transport networksFocus: Optical & other transport networks G.ASON – Automatically Switched Optical G.ASON – Automatically Switched Optical

NetworkNetworkAddresses the control layer for intelligent Addresses the control layer for intelligent

optical networksoptical networks

Ambition to reference IETF standardsAmbition to reference IETF standards

36

OIF Optical UNI Signaling

Uses procedures and messages defined for MPLS traffic Uses procedures and messages defined for MPLS traffic engineering and GMPLSengineering and GMPLS

FeaturesFeatures Runs in UNI-only mode (overlay model) Runs in UNI-only mode (overlay model) Optical path creation, modification, and deletionOptical path creation, modification, and deletion Optical path status inquiry and responseOptical path status inquiry and response

Allows one protocol to support two different Allows one protocol to support two different applicationsapplications OIF UNI: client bandwidth requests (hide optical topology)OIF UNI: client bandwidth requests (hide optical topology) GMPLS: service provider provisioning (expose optical topology)GMPLS: service provider provisioning (expose optical topology)

IETF-GMPLSOIF-UNI

OpticalTransmission

Network

UNI

UNI

UNI

UNI

UNI

UNI

37

Agenda

History of IP BackbonesHistory of IP Backbones

The Emerging Two Layer NetworkThe Emerging Two Layer Network

Network PlatformsNetwork Platforms

Standards and ForumsStandards and Forums

GMPLSGMPLS

38

Traditional MPLS Applications

Traffic Engineering

Layer 3 Routing Traffic Engineered LSP

Source Destination

VPNs

FT/VRS

Site 2

Site 3

Site 1

Site 1

Site 3

Site 2

CPE

CPE

CPE

PE PE

PE

P

P

P

P

P

PE

FT/VRF

FT/VRF

FT/VRF

FT/VRF

FT/VRF

CPE

CPE

CPE

FT/VRF

39

Generalized MPLS (GMPLS)

Traditional MPLS supports packet & cell Traditional MPLS supports packet & cell switching switching

Extends MPLS to support multiple switching Extends MPLS to support multiple switching typestypes TDM switching (SDH/SONET)TDM switching (SDH/SONET) Wavelength switching (Lambda)Wavelength switching (Lambda) Physical port switching (Fiber)Physical port switching (Fiber)

Peer modelPeer model Uses existing and evolving technologyUses existing and evolving technology Facilitates parallel evolution in the IP and optical Facilitates parallel evolution in the IP and optical

transmission domainstransmission domains Enhances service provider revenuesEnhances service provider revenues

New service creationNew service creation Faster provisioningFaster provisioning Operational efficiencies Operational efficiencies

40

GMPLS Mechanisms

IGP extensionsIGP extensions Forwarding adjacencyForwarding adjacency LSP hierarchyLSP hierarchy Constraint-based routingConstraint-based routing Signaling extensionsSignaling extensions Link Management Protocol (LMP)Link Management Protocol (LMP) Link bundlingLink bundling

41

IGP Extensions

OSPF and IS-IS extensions OSPF and IS-IS extensions Flood topology information among IP routers and OXCsFlood topology information among IP routers and OXCs New link typesNew link types

Normal link (packet)Normal link (packet) Non-packet link (TDM, Non-packet link (TDM, , or fiber), or fiber) Forwarding adjacency (FA-LSP)Forwarding adjacency (FA-LSP)

42

IGP Extensions

OSPF and IS-IS extensions OSPF and IS-IS extensions Flood topology information among IP routers and OXCsFlood topology information among IP routers and OXCs New link typesNew link types

Normal link (packet)Normal link (packet) Non-packet link (TDM, Non-packet link (TDM, , or fiber), or fiber) Forwarding adjacency (FA-LSP)Forwarding adjacency (FA-LSP)

43

IGP Extensions

New Link Type sub-New Link Type sub-TLVsTLVs

Link protectionLink protection Protection capabilityProtection capability AttributesAttributes

None, 1+1, 1:N, or None, 1+1, 1:N, or ringring

Priority for a working Priority for a working channelchannel

1:1 Protection

1:3 Protection

Working

Protection

Working

Protection

44

IGP Extensions

New Link Type sub-TLVsNew Link Type sub-TLVs Link descriptorLink descriptor

Characteristics of the linkCharacteristics of the link Selected attributesSelected attributes

Link typeLink type SONET, SDH, clear, SONET, SDH, clear,

Gig E, 10 Gig EGig E, 10 Gig E Minimum reservable bandwidthMinimum reservable bandwidth Maximum reservable bandwidthMaximum reservable bandwidth

Attributes change over timeAttributes change over time Provides a new constraint Provides a new constraint

for LSP calculationfor LSP calculation Shared Risk Link Group Shared Risk Link Group

(SRLG)(SRLG) List of the link’s SRLGs List of the link’s SRLGs Does not change over timeDoes not change over time

1:1 Protection

1:3 Protection

Working

Protection

Working

Protection

45

Forwarding Adjacency

A node can advertise an LSP into the IGPA node can advertise an LSP into the IGP Establishes LSP using RSVP/CR-LDP signalingEstablishes LSP using RSVP/CR-LDP signaling IGP floods FA-LSPIGP floods FA-LSP Link state database maintains conventional links and FA-LSPsLink state database maintains conventional links and FA-LSPs

A second node wanting to create an LSP can use an FA-LSP as A second node wanting to create an LSP can use an FA-LSP as a”link”a”link”in the path for a new, lower order LSP in the path for a new, lower order LSP

The second node uses RSVP/CR-LDP to establish label bindings for The second node uses RSVP/CR-LDP to establish label bindings for the lower order LSPthe lower order LSP

ATMSwitch

ATMSwitch

SONET/SDHADM

Ingress Node(High Order LSP)

Egress Node(High Order LSP)

FA-LSP

Ingress Node(Low Order LSP)

Egress Node(Low Order LSP)

SONET/SDHADM

46

Forwarding Adjacency

ATMSwitch

Ingress Node(High Order LSP)

Egress Node(High Order LSP)

Ingress Node(Low Order LSP)

Egress Node(Low Order LSP)

IGP attributes describing a forwarding adjacencyIGP attributes describing a forwarding adjacencyLocal (ingress) and remote (egress) interface IP Local (ingress) and remote (egress) interface IP

addressesaddressesTraffic engineering metricTraffic engineering metricMaximum reservable bandwidthMaximum reservable bandwidthUnreserved bandwidthUnreserved bandwidthResource class/color (administrative groups)Resource class/color (administrative groups)Link multiplexing capability (packet, TDM, Link multiplexing capability (packet, TDM, , or fiber) , or fiber)Path information (similar to an ERO)Path information (similar to an ERO)

ATMSwitch

SONET/SDHADM

FA-LSPSONET/SDHADM

47

LSP Hierarchy

FA-LSC

FA-TDMFA-PSC

BundleFiber n

Fiber 1

FSC CloudLSC

CloudTDM

CloudPSC

CloudLSC

CloudTDM

CloudPSC

Cloud

ExplicitLabel LSPs

Time-slotLSPs Fiber LSPs LSPs

ExplicitLabel LSPs

Time-slotLSPs

(Multiplex Low-order LSPs) (Demultiplex Low-order LSPs)

LSPs

Nesting LSPs enhances system scalability Nesting LSPs enhances system scalability LSPs always start and terminate on similar interface typesLSPs always start and terminate on similar interface types LSP interface hierarchyLSP interface hierarchy

Fiber Switch Capable (FSC) HighestFiber Switch Capable (FSC) Highest Lambda Switch Capable (LSC)Lambda Switch Capable (LSC) TDM CapableTDM Capable Packet Switch Capable (PSC) LowestPacket Switch Capable (PSC) Lowest

48

Constraint-based Routing

Reduces the level of manual configurationReduces the level of manual configuration Input to CSPFInput to CSPF

Path performance constraintsPath performance constraints Resource availabilityResource availability Topology informationTopology information

(including FA-LSPs)(including FA-LSPs)OutputOutput

Explicit route for GMPLS signalingExplicit route for GMPLS signaling

Extended IGPExtended IGP

RSVP SignalingRSVP Signaling

Explicit RouteExplicit Route

UserUserConstraintsConstraintsRouting TableRouting Table Traffic EngineeringTraffic Engineering

Database (TED)Database (TED)Constrained ShortestConstrained Shortest

Path First (CSPF)Path First (CSPF)

49

GMPLS Signaling Extensions

Label Related Formats (“Generalized Labels”)Label Related Formats (“Generalized Labels”)Generalized label requestGeneralized label request

Link protection type (none, 1+1, 1:N, or ring)Link protection type (none, 1+1, 1:N, or ring)LSP encoding type (packets, SONET, SDH, clear, DS-0, DS-1, LSP encoding type (packets, SONET, SDH, clear, DS-0, DS-1,

…)…)Generalized label objectGeneralized label object

Packet (explicit in-band labels)Packet (explicit in-band labels)Time slots (TDM)Time slots (TDM)Wavelengths (lambdas)Wavelengths (lambdas)Space Division Multiplexing (fiber)Space Division Multiplexing (fiber)

Suggested labelSuggested labelLabel can be suggested by the upstream nodeLabel can be suggested by the upstream nodeSpeeds LSP setup timesSpeeds LSP setup times

Label setLabel setRestrict range of labels selected by downstream nodesRestrict range of labels selected by downstream nodesRequired in operational networksRequired in operational networks

50

SONET/SDHADM

SONET/SDHADM

RESV

PATH

GMPLS Signaling Extensions

Bi-directional LSPsBi-directional LSPs Resource contention experienced by reciprocal LSP using separate Resource contention experienced by reciprocal LSP using separate

signaling sessionssignaling sessions Simplifying failure restoration in the non-PSC caseSimplifying failure restoration in the non-PSC case Lower setup latencyLower setup latency

RSVP notification messagesRSVP notification messages Notify message informs non-adjacent nodes of LSP eventsNotify message informs non-adjacent nodes of LSP events Notify-ACK message supports reliable deliveryNotify-ACK message supports reliable delivery

Egress controlEgress control Terminate LSP at a specific output interface of egress LSRTerminate LSP at a specific output interface of egress LSR

51

Link Management Protocol

The link between two nodes consists ofThe link between two nodes consists ofAn in-band or out-of-band control channelAn in-band or out-of-band control channelOne or more bearer channelsOne or more bearer channels

Link Management Protocol (LMP) Link Management Protocol (LMP) Automates link provisioning and fault isolationAutomates link provisioning and fault isolationAssumes the bi-directional control channel is always Assumes the bi-directional control channel is always

available available Control channel is used to exchangeControl channel is used to exchange

Link provisioning and fault isolation messages (LMP)Link provisioning and fault isolation messages (LMP)Path management and label distribution messages Path management and label distribution messages

(RSVP or CR-LDP) (RSVP or CR-LDP) Topology information messages (OSPF or IS-IS)Topology information messages (OSPF or IS-IS)

Control ChannelBearer Channel

LMP LMPLMP LMP

52

Link Management Protocol

Control channel managementControl channel management Lightweight keep-alive mechanism (Hello protocol)Lightweight keep-alive mechanism (Hello protocol) Reacts to control channel failuresReacts to control channel failures

Verify physical connectivity of bearer channelsVerify physical connectivity of bearer channels Ping test messages sent across each bearer channelPing test messages sent across each bearer channel

Contains sender’s label [(fiber, Contains sender’s label [(fiber, λ) pair] object λ) pair] object for channelfor channel Eliminates human cabling errorsEliminates human cabling errors

Link property correlationLink property correlation Maintains a list of local label to remote label mappingsMaintains a list of local label to remote label mappings Maintains list of protection labels for each channelMaintains list of protection labels for each channel

Fault isolationFault isolation ““Loss of light” is detected at the physical (optical) layerLoss of light” is detected at the physical (optical) layer Operates across both opaque (DXC) and transparent (PXC) Operates across both opaque (DXC) and transparent (PXC)

network nodesnetwork nodes

Services Provided by LMP

53

Multiple parallel links between nodes can be advertisedMultiple parallel links between nodes can be advertisedas a single link into the IGPas a single link into the IGP

Enhances IGP and traffic engineering scalabilityEnhances IGP and traffic engineering scalability Component links must have the sameComponent links must have the same

Link typeLink typeTraffic engineering metricTraffic engineering metricSet of resource classesSet of resource classesLink multiplex capability (packet, TDM, Link multiplex capability (packet, TDM, λλ, port), port)

(Max bandwidth request) (Max bandwidth request) (bandwidth of a component link) (bandwidth of a component link) Link granularity can be as small as a Link granularity can be as small as a λλ

Bundled Link 1

Bundled Link 2

Link Bundling

54

GMPLS Benefits

Open standards allow selection of best-in-class Open standards allow selection of best-in-class equipmentequipment

Routers have visibility into the transmissionRouters have visibility into the transmissionnetwork topologynetwork topology Eliminates NEliminates N22 meshes of links scaling issue meshes of links scaling issue Reduces routing protocol stressReduces routing protocol stress Optical paths span an intermix of routers and OXCs to Optical paths span an intermix of routers and OXCs to

deliver provisioning-on-demand networkingdeliver provisioning-on-demand networking

Leverages operational experience with MPLS-TELeverages operational experience with MPLS-TE No need to reinvent a new class of control protocolsNo need to reinvent a new class of control protocols Promotes parallel evolution of UNI and NNI standardsPromotes parallel evolution of UNI and NNI standards Enables rapid development & deployment of new OXCsEnables rapid development & deployment of new OXCs

55

GMPLS: Modern Thinking for Modern Times

Aligns with the way that the next generation network needs Aligns with the way that the next generation network needs to be built and managedto be built and managed

20th Century – Transmission network was dominant20th Century – Transmission network was dominant Voice ran over the transmission networkVoice ran over the transmission network ATM/Frame Relay delivered private data servicesATM/Frame Relay delivered private data services Internet was just one among many servicesInternet was just one among many services Transmission network created subscriber servicesTransmission network created subscriber services

21st Century – Internet is dominant21st Century – Internet is dominant Routers create the services that matter ($)Routers create the services that matter ($) Network must be optimized for IP/InternetNetwork must be optimized for IP/Internet OC-48/OC-192 make routers the largest consumers of bandwidthOC-48/OC-192 make routers the largest consumers of bandwidth New architecture is driven by routers subsuming functions New architecture is driven by routers subsuming functions

previously performed by the transmission networkpreviously performed by the transmission network The transmission network must evolve in a way that is most The transmission network must evolve in a way that is most

beneficial to the creation of Internet services beneficial to the creation of Internet services

56Copyright © 2000, Juniper Networks, Inc.

Thank You

http://www.juniper.nethttp://www.juniper.net