1

Provisioning CERNET with Dark Fiber

Xing Li , Congxiao BaoCERNET Center

<2003-04-08>

2

Outline

Background

CERNET Optical Network

Operation Experience

Perspective

3

CERNET

China Education and Research Network is one of

the 10 national IP backbones in Mainland China

CERNET is the 2nd largest IP backbone

The equipment founding came from MoE and

State Planning Commission

The Operation is self funded

4

CERNET Link History

1995– 64K leased lines link to 8 regional network centers

1996– 512K leased lines link to 8 regional network centers

– 9.6K X.25 or 64K leased line to 28 provincial centers

1997– 3.7M point-to-point satellite link to 8 regional network centers

– 64K point-to-point satellite link to 12 remote provincial centers

1999– 155M SDH link to 8 regional network centers

5

CERNET Layer 3 Topology

徐闻

长春

哈尔滨

乌鲁木齐

拉萨

西宁兰州

银川

呼和浩特

台北

沈阳

南昌

西安 徐州

武汉 合肥

郑州

石家庄

北京

南宁

广州

福州

杭州上海

南京

天津

贵阳

海口三亚

湛江

无锡

大连

太原 济南 烟台

成都

长沙

重庆 黄梅

九江

昆明

青岛

汕头

唐山

汉中

宜昌

珠海深圳

惠州

柳州百色 厦门

主干网地区网

GigaPopPop

桂林

深圳

6

CERNET Statistics

36 PoPs covers all the provincial capitals

More than 1,000 universities located in 200+ cities

Currently about 10M users

There are 320M Students in China

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大连

北京

郑州

石家庄

武汉 合

肥

南京

上海

长沙

南昌 杭

州

广州

福州

成都

昆明

重庆

厦门

海口

桂林

沈阳

哈尔滨天津

济南

南宁

深圳

太原 青岛

GZ

SHNJWH

BJSY

XA

CD

CERNET Dark Fiber Topology

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Current Architecture

DWDM 16x2.5G Lucent

SDH 16x155M Lucent

Router Cisco Router Cisco

2.5G

2.5G

155M

Dark Fiber

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CERNET Transport Network

Transport network

– 20,000 km

– 200+ relay stations

– DWDM 16x2.5G

– SDH 155M

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Three Types DWDM sites

OA: Optical Amplifier

Terminal

Dual-Face

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CERNET DWDM System

16x2.5G DWDM system (two lambda’s are currently runni

ng)

OC48 POS links to 8 cities

OC3 POS SDH links to all provincial capitals (except Lhas

a)

unicast and multicast

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DWDM System

1550

1551

1552

1553

1554

1555

1556

1557

0

1

2

3

4

5

6

7

TransmitReceive 3R

1550

1551

1552

1553

1554

1555

1556

1557

0

1

2

3

4

5

6

7

Transmit Receive 3R

0

1

2

3

4

5

6

7

0

1

2

3

4

5

6

7

20 ppm

50 ppm

PLL

50 ppm

PLL

LOOPTIMING

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Hut Spacing

Span Span Span

Span Span Span SpanOptical

Amplifier

SpanRegenerator

Hut Spacing: 40 km vs 65 km vs 100 km vs … x km

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Power Budget

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Configuration of Terminal Site

OTU1

OTU2

OTUn

OM

U

OTU1

OTU2

OTUn

OD

U

OA

OA

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Configuration of Dual-Face Site

OTU1

OTU2

OTUn

OM

U

OTU1

OTU2

OTUn

OD

U

OA

OA

OD

UO

MU

OA

OA

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Typical Site Configuration Example

To Beijing To Hefei

(Ring1)

OLS80G6x155M(e)+4x155M(e)

To Guangzhou5x155M(e)

ADM16/1

(Ring2)

(Ring3)

2.5G To Beijing2.5G To Nanjing

2.5G To Guangzhou

TimingTSG3800

PRR-10 GSP48VPower

To University

9x155M(o)+5x155M(o)+4x155M(o)

ADM16/1

ADM16/1

ADM16/1

2x15

5Me)

ADM16/1

3x155M(e)4x155M(e)

OLS80G

3c

3c

9c1c

2c

3c

3c

1c

2c

9c

9c

2c

1c 1c

9c

4c2.5G To Chengdu

4x155M(e)

To Chengdu

2c

4c

3c

9c

OLS80G

OLS80G

OLS80G

OLS80G

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Stations

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Some Reality

Because POS interface is wavelength insensitive,

OTU need not to be used after ODU.

Because DWDM system is point-to-point connection

and has no self-healing capability, layer 3 routing

restoration must be depended in case of fiber

break.

Optical character test of optical interface must be

done periodically because of aging both in

equipment and fiber.

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CERNET Backbone Bandwidth

CERNET

US

0.001

0.1

10

1000

100000

10000000

Dec-

94

Dec-

96

Dec-

98

Dec-

00

Dec-

02

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Backbone Traffic

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CoreRouter

CoreRouter

CoreRouter

CoreRouter

CoreRouter

CoreRouter

borderRouter

EdgeRouter

EdgeRouter

EdgeRouterEdge

Router

EdgeRouter

2.5G POS

WAN

Guangzhou

Shanghai

Beijing

GELAN

GELAN

GELAN

GELAN

GELAN

GEMAN

To Japan

User Network (IPv6)

MAN/LAN

MAN/LAN

CERNET DWDM for IPv6-CJ Testbed

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Next Step

ELH for 3,500 km DWDM system– Remove SDH Layer

– Use OADM Unified Management System

– Optical

– IP

OXC– Traffic Engineering

CWDM for the MAN– City PoPs

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CapEx and OpEx is Reduced by ELH-DWDM

Replacing O-E-O by OA

2,000 km

EDFA/RAMAN

O-E-O Regenerator

Terminal Site

650 km 650 km

Terminal Site

650 km

EDFA EDFA EDFA

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Unified Control Plane (UCP)

Addressing, Routing, and Signaling ProtocolsAddressing, Routing, and Signaling Protocols

Common Set of Control Functions

Control Network

Generalized across Disparate Transport TechnologiesGeneralized across Disparate Transport Technologies

UCP Beneficiaries and Functions

End User On Demand, Optical Channel Provisioning

Transport Provider Low Cost Per Bit Data Aware Optimization

Application Provider New, Differentiated Services—At a Profit

UCP Beneficiaries and Functions

End User On Demand, Optical Channel Provisioning

Transport Provider Low Cost Per Bit Data Aware Optimization

Application Provider New, Differentiated Services—At a Profit

IP IP

MetroDWDMMetro

DWDMCore

DWDMMetro

SONETMetro

SONET

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Fiber ring OIX with OBGP

Figure 11.0

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850nm ： 778nm 、 801nm 、 825nm 、 850nm

O—Band:1275.5nm 、 1300.2nm 、 1324.7nm 、 1349.2nm

（ 1290 、 1310 、 1330 、 1350 ）

E—Band:1380 nm 、 1400nm 、 1420nm 、 1440nm

S+C+L Band:1470nm 、 1490nm 、 1510nm 、 1530nm 、 1550nm 、 1570nm 、 1590nm 、 1610nm

Spectrum of CWDM

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CNGI

Testbed

Test and Measurement

Network Services

Demo Applications

Commercial Services

Network Equipment