GMPLS Actively Managed WDM Testbed · GMPLS Actively Managed WDM Testbed Y. J. (Ray) Chen...

UMBCLTS Review 2003 p1

GMPLS Actively Managed WDM Testbed

Y. J. (Ray) ChenDepartment of CSEE, UMBC

[email protected]


ObjectivelActively managed GMPLS Network

– Actively managed reconfigurable WDM optical network» Ultra-high capacity (~10Tps)» Scalability and efficiency of bandwidth utilization» Reconfiguration is buit into the traffic engineering process

– Delivery of quality of service (QoS)» Capable of providing variable levels of QoS according to service level

agreements (SLAs)– Considerable resiliency

» Prompt detection of failures» Fast protection switching/restoration

– Advanced network control and management

lBase on optical Ethernet – Internet traffic is dominated by Ethernet packets – Introduces QoS traffic engineering and Differentiated service– Low cost line rate and Ethernet switch devices– Very efficient packet delivery


Current GMPLS and Optical Ethernet Approachesl Inefficiency of current GMPLS implementation

– All-optical routing in the core region of the network» Coarse traffic granularity» High traffic blocking rate» Limited reconfiguration capability» No grooming; bandwidth utilization efficiency is limited

– MPLS and optical layers are managed separately» Complicates the OAM&P

– Layer 2 is passive and non-reconfigurable

l Difficulties of current Optical Ethernet– No carrier-class QoS– Lack of efficient OAM&P methods– Inefficient protection/restoration schemes

l Existing improvement attempts on Optical Ethernet– Resilient Packet Ring (RPR)

» Specially designed MAC for packet transport over fiber-optic rings» Introduces SONET-like protection and restoration schemes to optical Ethernet» Not suitable for other regular topologies, e.g., mesh topology

– Layer-3 switching» Merges layer 2 switching and layer 3 routing functions to a single switch box» Utilizes reconfigurable features of layer 2 to some extent

OXC

OXC OXC

OXC

OXC

OXC

O X C

Optical LayerOXC

MPLS Core Router

OXC/OADM

MPLS Edge Router

MPLS Layer

Combination of GMPLS and optical Ethernet–Incorporates both QoS and resilience features of GMPLS and efficiency of Ethernet


Our GMPLS Testbed

ü Implements an Integrated Reconfigurable Ethernet (layer 2) + Optical Switching Layer

− Even with legacy Ethernet switches (routing and signaling protocols required)

− Integrated management of the optical layer and Ethernet layer through QoS traffic engineering

üEnables traffic grooming and O/E/O wavelength conversion at the core of the network

üWavelength information and MAC addresses are utilized collectively to perform the GMPLS “label”functions


System Architecture

Ethernet Layer

OXC

OXC OXC

OXC

OXC

OXC

OXC

Optical Layer

OXC

MPLS Core Router

OXC/OADM

MPLS Edge Router

IP/MPLS Layer

Ethernet switch

â The label structureλ MAC Label EXP S TTL

L1 Label L2 Label MPLS Label

ã Three forwarding schemesall-opticalO/E/O at Ethernet layerO/E/O at IP/MPLS layer

– Different forwarding scheme can have different QoS level, e.g., bandwidth, latency, jitter, etc.

OXC


Benefitsl QoS path provisioning

– The device performance/response parameters are calibrated for each QoS level

– QoS paths are set up according to the committed service level agreement (SLA)

– Paths can be adjusted, i.e., reconfigured, according to traffic engineering decision

l QoS path performance improvement– Path latency reduction

l Efficient bandwidth utilization through O/E/O wavelength conversion and traffic grooming

l Potential system cost reduction– Inexpensive Ethernet switch devices– Low cost Ethernet deployment– Fast service provisioning


Hardware subjects for UMBC MPλS Testbed


The UMBC GMPLS Optical Testbed

l 9 optical nodes– IP/MPLS router– Ethernet switch– OXC

l 4 operational wavelengths– 100/1000Mbps line rate

lWeb-accessible GUI interface

L05-3

5 6 7 811 12 13 14

9 10 19 20

23 32 36 37

P5 P6 P7j5 P8j6 j7 j8

L07-3 L07-4 L08-3 L08-4

5 61211 13 14

22 26

41 42 43 101

P5 P6 P7j5 P8j6 j7 j8

28

L4-4

45

L06-3

15

L10-4

1

L10-3

5

915

103

i101

i2 02

i3o3

i4o4

o3i3

p0

i2o2

i6

i7

o6

o7

i8

o8

i1o1

NIC

1

i5 o5

i4

L9-4

6

j0 p0

L12-2

111

L06-4

16

L12-4

25

L12-1

110

NIC

1N

IC2

NIC

3N

IC4

NIC

5

NIC

1

NIC

2N

IC1

NIC

2

NIC

1

NIC

2

NIC

1N

IC2

NIC

3

NIC

4N

IC5

NIC

2

NIC

2

NIC

1L11-3

31

L12-5

NIC

1

NIC

2

i4 o4

L05-4

38

o4

Category 5 cable

SC connector

Multimode fiber

BNC-SMA cable

Single-mode fiber

PC/SC connectorL0x-3Laser

Transponder

ConverterNICGigabit NIC

GMPLS router

layer2 switch

OXC

ER1-2

CR1 CR2

CR3

ER1-1

ER2-1

ER2-2

ER3-1 ER3-2

L09-3

102

j0

NIC

1

NIC

2

i5o5

i6 o6 i7

i8

o7

o8

i2

o2

i1 o1

o3

i3

o8i8

i7o7

i6

i5

o6

o5

L3-3 L3-4 L04-3

GUI-Server

L12-3

24

Signaling channel


Traffic Generator and Testing Software

l Software: based on the 3rd party software as follows – Netperf

» Used to generate background traffic» Used to randomly generate traffic» Used to generate multiple user sessions

– Iperf 1.1.1» Used to test the packet drop rate (PDR), Packet Jitter,

User throughput

– ICMP Ping» Use to get the path round-trip latency


PC throughput capability

93%(iperf)3.52G(iperf)UDP STREAMClientDell SC600

83%2.33GUDP STREAMCR

UDP STREAM

TCP STREAM

TCP STREAM

TCP STREAM

DATA TYPE

70%2.53MER3-1,ER3-2ER2-2,ER2-1

96%(netperf)91~94%(iperf)

2.231G(netperf)2.2G(iperf)

ER3-1,ER3-2ER2-2,ER2-1

98%(netperf)92~96%(iperf)

2.290G(netperf)2.2G(iperf)

CR

95%(iperf)95%(netperf)

3.51G(iperf)4.1G(netperf)

Client Dell SC600

CPU utility rate-system

Maximum TCP (loopback) /UDPthroughput

l Experiment setup: local loopback


Path Latency Reduction

Note:•Test results are extracted from the 9-node UMBC Optical testbed.•Results only show single node latency.•Equipments used in the measurement : Cisco Catalyst 3550 router, Intel 100Mbps Ethernet switch,

PC-based NIST MPLS switch (Pentium 4 @ 2.0Ghz). •In this test, Layer 2.5 latency is limited by our home-built MPLS switch. Layer 2.5 latency should be

smaller if commercial MPLS switches are used.•Real values of throughput and latency may vary, if different router/switch/OXC devices were used.

However similar performance behavior is expected.

0.10

0.15

0.20

0.25

0.30

100 200 300 400 500 600 700

Layer 3 latencyLayer 2.5 latencyLayer 2 latencyLayer 1 latency

Traffic Load (Mbps)

Late

ncy

(ms)


Analysis on Bandwidth Utilization Efficiency

Note:•The comparison is based on the 30-nodes NSFNET topology assuming that each node has full L2 O/E/O

capability•Each individual bandwidth request <=2Mbps•All traffics are Internet best-effort traffic•All-optical : adaptive routing and first-fit (FF) wavelength assignment•O/E/O: standard SPF calculation

ã Comparison of system blocking probability ã Comparison of bandwidth utilization on a single node

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

2 4 6 8 10 12 14 16 18 20

All-optical RouteL2 O/E/O Route

Wavelength # = 16

ErLang

Blo

ckin

g P

roba

bilit

y

0.2

0.3

0.4

0.5

0.6

0.7

0 5 10 15 20

L2 O/E/O RouteAll-optical Route

Wavelength # = 16

ErLang

Ban

dwid

th u

tiliz

atio

n


Efficiency of Traffic Grooming

Note:•Test results are acquired from the UMBC Optical testbed•Equipments used in the measurement : Cisco Catalyst 3550 router, Intel 100Mbps Ethernet switch•Real values of throughput and latency may vary, if different router/switch/OXC devices were used.

However similar performance behavior is expected.

0.6

0.8

1.0

1.2

1 2 3 4 5 6 7 8

Grooming effiency on a 100Mbps Router portGrooming effiency on a 100Mbps Ethernet port

Number of users

Thro

ughp

ut (

100%

)


GMPLS Operating System Design Issues

for UMBC MPλS Testbed


The Operating System Is Based On…

l RFC GMPLS, MPLS Draftsl FreeBSD Rel. 3.3l NIST MPLS Switch enginel Alternative Queuing (ALTQ)l ReSerVation Protocol (RSVP) + TE

extensionl OSPF-TE


Our Special Considerations

l We assume full network-awareness at each node– A cluster network environment

l The QoS condition is treated as a binary constraint– Bandwidth, latency, packet drop rate

l No splitting trafficl Traffic history is not considered

» Routing decisions are made independent of past traffic pattern

l Dynamic cost factor modell Routing calculations based on heuristics


Routing & Signaling Process

Newrequest

PreferredRouting

Best-effortRouting

Signaling(Path Setup)

DataTransmission

NetworkStatusupdate

Trafficmeasurement

Error noderesponsible to find an

alternative routebetween itself anddestination node

Reject (Pathblocked)

Send errorinformation to

source node, wherean alternative route

is searched

Successful?

PremiumRouting

Successful?

No, Premium/ Preferred

Yes


No,Best-effort

No,Maximumretry timeexceeded


No, Maximum retrytime exceeded

NoNo

No

Successful

No

Yes

Hold request andWait for globalsynchronization


Routing – Dynamic Problem

l Given – Current network status– A set of QoS requests arriving one at a time

l Objective– Maximize total number of successful connections

l Constraints– Bounded QoS for premium and preferred services– Wavelength continuity constraint at each fiber– Grooming constraint : total bandwidth of premium and

preferred service at any Ethernet switch port cannot exceed the maximum physical outgoing bandwidth

» Assuming the Ethernet switch has DiffServ capability– Reconfiguration policy


Routing Design

Delay-Constrained Least-Cost Routing (DCLC)

l Graph Extraction Problem l S2 : Design of the Cost Functionl S3 : Design of the Delay Functionl S4 : Routing Heuristic


Graph Extraction

– Physical node extraction

oeocV ,

AdjacentNode 1

oxcincV ,

AdjacentNode 2

AdjacentNode 3

AdjacentNode 2

AdjacentNode 3

oxcoutcV ,

Wavelength 1

AdjacentNode 1

oxcincV ,

AdjacentNode 2

AdjacentNode 1

AdjacentNode 2

AdjacentNode 3

oxcoutcV ,AdjacentNode 3

Wavelength 2


Routing – Sub-Problem 1

l S1 : Two-Pass Dijkstra for DCLC– First pass : calculate least delay LDu from

every node u to destination node d and establish the feasible subset of nodes D(LDu’) < D

– Second pass : calculate least cost path from source s to d ; at each relaxation, count only nodes u’ that have D(LDu’) + delay so far <= D

– Time complexity : O(nlog(n)+m)– The path found by DCLC is a feasible path


Two-Pass Dijkstra : Simulations• NSFNET topology (32 nodes)• Uniformly generated cost&delay on the graph

1

3

2

45

6 17

13

7

9

16

14

15

12

11

10

18

21

1924

2223

25

29

27

28

30

32

31

20

268


Two-Pass Dijkstra : Simulations• NSFNET topology (32 nodes)• Uniformly distributed cost&delay factors on the graph

200

240

280

320

360

150 200 250 300

Optimal PathLeast Delay PathTwo-Pass Dijkstra

Delay Constraint

Cos

t

.1-1% inefficiency


Two-Pass Dijkstra : Simulations• NSFNET topology (32 nodes)• Uniformly generated cost&delay on the graph

226.3226.4226.5226.6226.7226.8226.9227.0227.1227.2227.3227.4227.5227.6227.7227.8227.9228.0228.1228.2228.3228.4228.5228.6

225 250 275

Optimal PathLeast Delay PathTwo-Pass Dijkstra

Delay Constraint

Cos

t


Conclusionsl A novel hybrid network scheme that applies GMPLS on

optical Ethernet is demonstrated– An integrated reconfigurable Ethernet (Layer 2) + Optical layer– QoS traffic engineering

» Efficient bandwidth utilization» Cost-effective

l The testbed is utilized to develop network control and management schemes

– Study advanced control plan issues

l Understand the issues related to actively managed network

– When, where and how to trigger network reconfiguration

l In our system, each data packet connection can be treatedas an independent circuit connection

– The system can be used to study networks with much larger dimension

GMPLS Actively Managed WDM Testbed · GMPLS Actively Managed WDM Testbed Y. J. (Ray) Chen...

Documents

Transcript of GMPLS Actively Managed WDM Testbed · GMPLS Actively Managed WDM Testbed Y. J. (Ray) Chen...