mpls traffic engineering1526

KNOM Tutorial 2001

MPLS Traffic Engineering & Management Issues

Taesang Choi

2001. 12. 7.

Internet Architecture TeamElectronics Telecommunications Research Institute

2KNOM Tutorial 2001

Topics

▣ MPLS-TE Basics▣ MPLS-TE Operational Issues▣ MPLS Management Issues▣ MPLS-TE Management Solutions

KNOM Tutorial 2001

MPLS-TE Basics

4KNOM Tutorial 2001

What is Traffic Engineering?

▣The task of mapping traffic flows onto an existing physical topology to facilitate efficient and reliable network operations

▣Check mpls & tewg working group documents for more well-versed definitions◈Requirements for Traffic Engineering Over MPLS (RFC 2702)◈A Framework for Internet Traffic Engineering (draft-ietf-tewg-

framework-05.txt)

5KNOM Tutorial 2001

Legacy Internet TE Efforts▣ IGP Metric-Based TE

◈Remember “fish problem?”◈Drawbacks?“Blame Shifting”: only serves to move problem around?Lacks granularity?Instability

▣Overlay Network Approach◈ATM core ringed by routers & overlaid PVCs on top of it◈Drawbacks?Full mesh overhead?Not well integrated?Cell Tax?ATM SAR speed

6KNOM Tutorial 2001

MPLS-TE Advantages

▣The physical path of the “traffic-engineered path” is not limited to what the IGP would choose as the shortest path to reach the destination

▣Variously divisible traffic aggregation and disaggregation

▣Maneuvering load distribution▣Stand-by secondary paths and precomputed detouring

paths▣Strongly unified measurement and control for each

“traffic-engineered path”

7KNOM Tutorial 2001

Vocabulary▣ LSP (Label Switched Path)

◈ the “traffic-engineered path”

▣ Primary and Secondary Paths◈ an LSP can contain a primary path & zero or more secondary paths

▣ Named Path◈ a sequence of explicit hops

LSP A

Primary Path Secondary Path

LSP B

Primary Path Secondary Path

Named Path 1

Named Path 2

8KNOM Tutorial 2001

Vocabulary – cont’d

▣Traffic Trunk (TT)◈an aggregation of traffic flows going from an ingress to an

egress◈ forwarded through a common path with common TE

requirements◈characterized by?its ingress and egress?FEC which is mapped to it?a set of attributes that determines its behavioral

characteristics

9KNOM Tutorial 2001

Vocabulary – cont’d

▣Types of LSPs◈Static LSPs?no relevance to TE

◈LDP signaled LSPs?no relevance to TE

◈RSVP/CR-LDP signaled LSPs?Explicit-path LSPs?Constrained-path LSPs?Note: both of the two above are not mutually exclusive!

10KNOM Tutorial 2001

Components of MPLS-TE

▣Packet Forwarding Component◈MPLS, label switching itself

▣ Information Distribution Component◈ IGP (OSPF/IS-IS) extension

▣Path Selection Component◈Constrained Shortest Path First (CSPF) algorithm

▣Signaling Component◈LDP, CR-LDP, and RSVP-TE

▣Not all of these required!


How everything fits into?

Link attributes

Link attributesmodification

RSVP signalingTED

LSP pathsCSPFLSP attributes

Routing table

advertised byIGP-extension

operatorinput

computes

structured as

reservationLSP

establishment

topology &resources

advertised byIGP-extension


MPLS-TE Mechanisms

▣LSP Routing◈with TE attributes (LSP & Link attributes)◈dynamic vs. explicit

▣Traffic Protection (Resilience)◈secondary paths and fast reroute

▣Path Reoptimization (Adaptivity)▣Load Sharing and Balancing

◈LSP-level traffic bifurcation

▣LSP Hierarchy◈ forwarding adjacency LSPs, unnumbered links

KNOM Tutorial 2001

MPLS-TE Deployment and Operational Issues


MPLS-TE Deployment Issues

▣ MPLS is proposed as a standard TE solution by IETF, BUT◈ Vendor Interoperability problem◈ Limitation in online path calculation◈ Problems on Traffic Trunks◈ Measurement and Control Issues


Interoperability

▣Vendor specific implementation details diverge!◈Almost everything but signaling standard might be different◈Using more than two heterogeneous families in a domain may

cause unpredictable operational problems

▣Need a unified abstraction system to hide, moderate, and arbitrate the differences


Limitation in Online Path Calc.

▣Online path calc. considers one LSP at a time◈undeterministic◈The order in which an LSP is calculated plays a critical role!

▣Global optimization required◈Optimization tools that simultaneously examine each link’s

resource constraints and the requirements of each LSPs all together are necessary


Problems regarding to TT

▣How to define traffic trunks?◈No standard◈Manual classification?requires TE policies?granularity and scalability concern?practically, only dest. prefix based classification supported?requires, so called, “policy routing”

◈BGP-based classification?Transit traffic whose route updates’next_hop is identical to the

egress of an LSP are routed over the LSP◈ Implicit classification by IGP


Problems regarding to TT – cont’d

▣How to map a traffic trunk’s attributes onto LSPs’constraints?◈need a global view◈must be able to anticipate the effect, to some extent◈must be able to rationalize?by simulations?by measurements?by policies?by intuition??by experience?


Measurement and Control▣Measurement

◈provides rationale and fundamental bases to induce proper TE constraints for TTs and LSPs?such as, traffic (demand) matrices, congestion indication,

LSP statistics, etc.◈methods?SNMP (various MIBs), CLI, Cisco Netflow and TMS, and/or

JUNOS MPLS Statistics, RTFM probes, etc.

▣Control◈manages TE policies?policy editing, conflict check, enforcement, withdrawal, etc.?customized to service specific policies, such as VPN

policies


MPLS-TE Operational Issues

▣ Prohibitive costs for manual provisioning for multi-node and multi-vendor environment◈ Longer educational curve◈ Single highly skilled operator or multiple vendor specific many

operators◈ Tighter and precise communications among them

▣ Error-prone manual configuration and hard to detect the semantic configuration errors (e.g., typos in path name)

▣ LSP operations diagnosis (e.g., when LSP setup fails, it is very difficult to pin point the exact reasons. The system doesn’t tell much useful info.)


Configurable LSP Attributes▣ Can specify the following attributes either for each LSP or for each

path belonging to the LSP◈bandwidth (traffic profile in CR-LDP)◈constrained (dynamic) vs. explicit path◈affinity◈adaptivity?reoptimize-timer, reoptimize-event

◈ resilience?(stand by) secondary paths, fast reroute

◈priority & preemption?setup, hold

◈ route record◈hop-limit, cos, etc.

KNOM Tutorial 2001

Juniper Example


Minimum MPLS Configuration

▣ Required of transit routers, as well as the ingress and egress

[edit]interfaces {

interface-name {logical-unit-number {

family mpls; # required to enable MPLS on this intf.}

}}protocols {

mpls {interface (interface-name | all); # required to enable MPLS on this intf.

}rsvp {

interface interface-name; # required for RSVP signaled MPLS only}

}


Create a Named Path▣ Named Path

◈ means a physical path from the ingress to the egress

▣ Named Path and LSP◈ Configuring an LSP may require multiple named paths?primary and secondaries

◈ can specify the same named path on any number of LSPs

▣ Syntax

[edit protocols mpls]path path-name {

address | host name <strict | loose>;}


Create an LSP▣ Rough Syntax

[edit protocols mpls]label-switched-path lsp-path-name {

to address; # egress addressfrom address; # ingress address

# lots of statements for setting various LSP attributes;

primary path-name {

# lots of statements for setting various path attributes;

}secondary path-name {

# lots of statements for setting various path attributes;

} }

KNOM Tutorial 2001

Cisco Example


Minimum MPLS Configuration▣ Required of transit routers, as well as the ingress and

egress

◈ Turn on MPLS tunnels ◈ Turn on CEF ◈ Turn on IS-IS or OSPF ◈ Syntax? Router(config)# ip cef

? Router(config)# mpls traffic-eng tunnels

? Router(config-if)# mpls traffic-eng tunnels

? Router(config-if)# ip rsvp bandwidth bandwidth

? Router(config)# router ospf process-id ? Router(config-router)# mpls traffic-eng area 0 ? Router(config-router)# mpls traffic-eng router-id loopback0


Create a Named Path▣ Named Path

◈ means a physical path from the ingress to the egress

▣ Named Path and LSP◈ Configuring an LSP may require multiple named paths?primary and secondaries

◈ can specify the same named path on any number of LSPs

▣ Syntax

Router(config)# ip explicit-path name path-c7204-m5 enableRouter(config)# next-address 10.2.0.29Router(config)# next-address 10.2.0.34Router(config)# next-address 10.2.0.33


Create an LSP▣ Rough Syntax

Router(config)# interface tunnel 2003Router(config-if)# description c7204-m402Router(config-if)# ip unnumbered Loopback0Router(config-if)# tunnel mode mpls traffic-engineeringRouter(config-if)# tunnel destination 203.255.255.234Router(config-if)# tunnel mpls traffic-eng autoroute announceRouter(config-if)# tunnel mpls traffic-eng priority 7 7Router(config-if)# tunnel mpls traffic-eng bandwidth 10000Router(config-if)# tunnel mpls traffic-eng path-option 1 explicit name path-c7204-m5Router(config-if)# tunnel mpls traffic-eng record-routeRouter(config-if)# exit Router(config)# router traffic-engineeringRouter(config)# traffic-engineering filter 1 egress 10.14.0.111 255.255.255.255 Router(config)# router traffic-engineeringRouter(config)# traffic-engineering route 1 tunnel 2003


MPLS FCAPS▣ MPLS Configuration Management

◈ Automating complex MPLS configuration rules (including TE rules)

▣ MPLS Fault Management◈ MPLS LSP status monitoring◈ MPLS Traffic Trunks/LSP fault analysis◈ Link/Node failure diagnosis

▣ MPLS Performance Management◈ LSP traffic measurement and analysis◈ MPLS network global optimization

▣ MPLS Accounting Management◈ Mapping measured traffic data into billing purpose◈ Mapping accounting data into admission control information

▣ MPLS Security Management


MPLS Service Management

▣ SLA Provisioning & Monitoring management◈ General MPLS service (e.g., traffic trunk lease) SLA◈ Service specific MPLS service (e.g., MPLS VPN) SLA

▣ Inter-domain MPLS Management◈ Protocol level distributed solution (e.g. inter-domain signaling

such as GMPLS) is one thing ◈ and management of this mechanism from network

administrator viewpoint is another

▣ Many issues are still left open

KNOM Tutorial 2001

MPLS TE Management Solutions


TE Servers: Products Introduction

▣WANDL, Inc. - MPLSView ®◈Automated data collection, layout, event collection and filtering

(mainly focused on pre-configured LSPs)◈A quasi real-time view on the configuration of the network,

including LSP set-up & state and per-LSP traffic flow◈Partnership with Cisco and Juniper

▣Makesystems, Inc. - NetMaker ®◈Network engineering and simulation tool for IP and MPLS◈Merged to OPNET Technologies, Inc.

▣Alcatel GRATE▣ETRI - Wise<TE> ®


VPN Servers: Products Introduction

▣Orchaestream▣Cisco’s VPN Solution Center▣Dorado▣ETRI - Wise<TE/VPN>

KNOM Tutorial 2001

Wise<TE/VPN>


Wise<TE> addresses Questions▣ How are packets routed in our network, and how are routing

protocols configured ?

▣ Why is this link so congested, while others are underutilized ?

▣ Which path is the best fit for an LSP to serve a new VPN flow without QoS degradation ?

▣ Why is this LSP’s operational / signaling state down?

▣ How much would it be worse if this node (link) fails?

▣ How much would it be better if our MPLS network is globally optimized by recomputing all LSPs together?

▣ Can we achieve some traffic engineering goals by global LSP reoptimization, routing metric optimization, or a totally new capacity planning process?


How!

subnet subnet

subnetsubnet

Area 1 Backbone AreaArea 2

TE/VPN Policies

Wise<TE>™

MIB Values

IP, LSP & VPN TrafficMeasurement Results

Visualizing Network, Routing &

VPN Topologyand Behavior

EnforcingRouting, TE and

VPN Policies

Routing Protocol Info.(TED)

SimulationLogics

(CSPF, etc.)

TE Path (LSP)

IGP Path

Operational Status


Main Functionality▣ LSP / VPN Configuration Management and Quasi-realtime

Monitoring

▣ Versatile Views of IP, MPLS, Routing (OSPF and BGP), and VPN Topology

▣ TE and VPN Policy Management

▣ IP Traffic Measurement and Analysis for MPLS-TE and VPN Management

▣ Intelligent Path Computation, Recommendation, and Various Simulations


Wise<TE> Architecture

ConfigurationPackage

MeasurementPackage

GlobalConfig

Package

MiscPackage

GUI

TMS

RMS

PS

RATE

CSI (Common Service Interfaces)

Proxy Agent

ACE2000JuniperRouter

CISCORouter

TMSAgent

RMSAgent

COPSAgent

JunoscriptClient

CiscoCLI

ACECLI

MeasuredTraffic Data

CORBA

OSPF/BGP

CORBA CORBA

TrafficMeasurement

ResultsSNMPPollingResults

TMS DB

RMS DB

PS DB PIB

CORBA

SNMP

CORBA

COPS


Easy Steps to create LSP Tunnels and Easy Steps to create LSP Tunnels and VPNsVPNs

ConfigurationPackage

MeasurementPackage

GlobalConfig

Package

MiscPackage

PS

COPS

TMSAgent

RMSAgent

COPSAgent

JunOSCLI

CiscoCLI

Proxy Agent

ACECLI

ACE2000JuniperRouter

CISCORouter

CORBA

GUI

CLI/Telnet

CORBA


Versatile Topology Views: IPVersatile Topology Views: IP

IP Topology View

+

-

AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

20 ~ 40

0 ~ 20

40 ~ 6060 ~ 8080 ~ 100

Link Utilization: %

LV


Versatile Topology Views:Versatile Topology Views:

MPLS View - LSP Tunnel Statistics

+

-

AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

20 ~ 40

0 ~ 20

40 ~ 6060 ~ 8080 ~ 100

LSP Statistics: %

LV

LSP Tunnel Intf: Tae-Suw-Seo, 600Mbps

MPLS LSP TrafficMPLS LSP Traffic

Per LSP Statistics

m10-to-m5 203.255.255.232

c7204-to-m10

m201-to-m5

m10-to-c7204

m5-to-m202

203.255.255.233

203.255.255.232

203.255.255.235

203.255.255.235

203.255.255.232

203.255.255.235

203.255.255.236

203.255.255.234

2344556

24980

47837593759

57843578

478593

BPSEgressIngressLSP Name

203.255.255.236

Show Path OK Help


Versatile Topology Views:Versatile Topology Views: MPLS Reserved MPLS Reserved BwBwMPLS View - Reserved Bandwidth

+

-

AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

20 ~ 40

0 ~ 20

40 ~ 6060 ~ 8080 ~ 100

Reserved Bw: %

LV


Versatile Topology Views:Versatile Topology Views: MPLS AffinityMPLS Affinity

MPLS View - Affinity

+

-

AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

2

1

345

Affinity: Colors

LV


Versatile Topology Views:Versatile Topology Views: MPLS Link & TunnelsMPLS Link & Tunnels

MPLS View - Links and Tunnels

+

-

AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

LV


Versatile Topology Views:Versatile Topology Views: Routing ProtocolsRouting ProtocolsRouting Protocol View - OSPF

+

-

AV

PV

LV

AS64514: Area0

ABR

IGP: OSPFRouting Protocol View - BGP

+

-

AV

PV

LV

AS64514

AS9270

AS64513

AS64512

AS64515


Routing Protocol View - BGP

+

-

AV

PV

LV

VPN#1

VPN#1

VPN#2

VPN#2

PE1:203.255.255.232

PE2:203.255.255.233

PE5:203.255.255.236

PE4:203.255.255.235

PE3:203.255.255.234

VPN Tunnels

L2 Links

VPN#1

VPN#2

Cisco

Juniper

Versatile Topology Views:Versatile Topology Views: MPLS/BGP VPNMPLS/BGP VPN


Various Simulations:Various Simulations: Path Availability CheckPath Availability Check

Simulation - Path Availablity Check: Step 2

Available Path was found. Do you want to see it?

OK Cancel

MPLS View - Reserved Bandwidth

+

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AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

20 ~ 40

0 ~ 20

40 ~ 6060 ~ 8080 ~ 100

Reserved Bw: %

LV


Various Simulations:Various Simulations: Link/Node FailureLink/Node FailureSimulation - Link/Node Failure: Step 1

Cancel

2001/10/23 17:30

Duration

17 2001

This simulation is to see what happens when a link failsDescription:

Simulation date:

Tunnel Link Failure SimulationSimulation name:

From: yearhour 30 min. 23 day Oct month

18 2001To: yearhour 00 min. 23 day Oct month

Next >>


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AV

PV

Seoul

Suwon

Taejon

Kwangju

Pusan

Taegu

20 ~ 40

0 ~ 20

40 ~ 6060 ~ 8080 ~ 100

Reserved Bw: %

LV

Simulation - Link/Node Failure: Step 2

Select failed links or nodes from the map. Then, click the OK button.

OK


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AV

PV

Seoul

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Taejon

Kwangju

Pusan

Taegu

20 ~ 40

0 ~ 20

40 ~ 6060 ~ 8080 ~ 100

Reserved Bw: %

LV

Traffic Flows thru Standby Secondary

LSP


LSP/Network Traffic Measurement and AnalysisLSP/Network Traffic Measurement and AnalysisLSP tunnel statistics

Name: LSP3 1000Reserved Bandwidth:

kbps

Save ClosePrint

Daily Weekly Monthly Yearly

bpscurrent : 343 bpsmaximum: 543 bpsminimum : 132 bps

ppscurrent : 343 ppsmaximum: 543 ppsminimum : 132 pps

0 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2 2 3 2 4

500

1000

0 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2 2 3 2 4

500

1000

2001 10 23- - Graph

Tunnel StatisticsTunnel Statistics

Traffic MatrixFile(F) Statstics(S) View(V) Tool(T) Help(H)

Graphics Matrix Color

20~40 %

0 ~ 20 %

40~60 %

60~80 %

80 ~100 %

In.Out Bound PrefixTransit

AS 4323AS 32AS 432AS 5654AS 61232AS 41AS 865AS 232

AS 12AS 24AS 4AS 2352AS 845

src dest

AS 4

AS 12

AS 24

AS 2352

AS 4

700

700

700

AS 12

300

400

400

AS 24

200

700

400

AS 2352

700

700

700

AS 845

700

700

700

700

AS 845 700 400 400 400

max : 2343avg : 1234min : 234

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

500

1000

2001-10-23 2001-10-23~Daily bps pps

AS Matrix Table & Graph ViewAS Matrix Table & Graph View



20~40 %

0 ~ 20 %

40~60 %

60~80 %

80 ~100 %


AS 4323AS 32AS 432AS 5654AS 61232AS 41AS 865AS 232

AS 12AS 24AS 4AS 2352AS 845

AS 4

AS 2352

AS 845

AS 12

AS 24

2001-10-23 2001-10-23~DailyWeeklyMonthlyYearly

bps pps

756 bps

AS Matrix Relationship ViewAS Matrix Relationship View



20~40 %

0 ~ 20 %

40~60 %

60~80 %

80 ~100 %


129.254/16129.254.191/24203.255.254.130/2763.43.62/2413.53/1654.33.53/24211.75.163/245/8

129.254.75/24211.13.232.192/2632.23/16234.23.123/2410/8

234.23.123/24

10/8

32.23/16

211.13.232.192/26

129.254.75/24

2001-10-23 2001-10-23~DailyWeeklyMonthlyYearly

bps pps

Prefix Matrix Relationship ViewPrefix Matrix Relationship View

mpls traffic engineering1526

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