Transporting Ethernet

Copyright Innocor Ltd. www.innocor.com

Gaoyao TangApplications Engineer, Innocor Ltd

April 2006

Copyright Innocor Ltd., 2006 www.innocor.com

Optical Ethernet -------An introduction

• LAN boundary extended to encompass the wide area networks (WAN) and metropolitan area networks (MAN).

• Ethernet over Fiber, Ethernet over WDM, Ethernet over PDH/SONET/SDH, Ethernet over digital wrapper and Ethernet over RPR, etc. are some of the enabling technologies.

• Virtual LAN service becomes popular thanks to Q-in-Q, MAC-in-MAC and VPLS

WAN or MAN

• This presentation discusses the techniques used for the transport of Ethernet over optical networks and the tests needed to evaluate a network’s ability to carry Ethernet frames

1GE or10 GE

1GE or10 GE


What is Ethernet80

2.10

Sec

urity

802.3MediumAccess

802.3Physical

802.4MediumAccess

802.4Physical

802.5MediumAccess

802.5Physical

802.6MediumAccess

802.6Physical

802.11MediumAccess

802.11Physical

802.12MediumAccess

802.12Physical

802.15MediumAccess

802.15Physical

802.16MediumAccess

802.16Physical

802.2 Logical Link

802.1 Bridging

802.

1 M

anag

emen

t

802.

Ove

rvie

w a

nd A

rchi

tect

ure

Ethernet : A LAN which couples the IEEE802.3 CSMA/CD MAC to a family ofthe IEEE802.3 Physical Layers.

Ethernet over … means the transport of the IEEE 802.3 MAC frame over a transport vehicle which may be SONET/SDH, WDM, OTN, RPR, …


Ethernet over fiber----1GE & 10GE

10GBASE-W1000BASE-SX (850nm)1000BASE-LX (1310nm)

ReconciliationMAC- Media Access Control (IEEE 802.3)

64B/66B PCS

10GBASE-R 10GBASE-X

PMAPMD

PMAPMD

8B/10B PCS

PMAPMD

WIS64B/66B PCS 64B/66B PCS

PMAPMD

8B/10B PCS

Reconciliation

• Ethernet in its native format, mainly full duplex operation

• Defined for 1G and 10G• Short operating distance• Transmission codes are

different for 1GE (8B/10B) and 10GE (64B/66B)

• Control information defined for link configuration (1GE) and link fault signaling (Local fault and remote fault)

1 Gigabit Ethernet and 10 Gigabit Ethernet

300m (S) /10km (L) /40km (E)64B/66B850(S)/1310(L)/1550(E) nm10 Gigabit Ethernet

550m (MMF), 5km (1310 SMF)8B/10B850/1310 nm1 Gigabit Ethernet

Operating distanceTransmission code

Wavelength


Examples of transmission codes

Input Data S

Y N C

Block Payload

Bit Position Data Block Format

01 2 65

D0D1D2D3/D4D5D6D7 01 D0 D1 D2 D3 D4 D5 D6 D7 Control Block Formats Block Type

Field

C0C1C2C3/C4C5C6C7 10 0x1e C0 C1 C2 C3 C4 C5 C6 C7 C0C1C2C3/O4D5D6D7 10 0x2d C0 C1 C2 C3 O4 D5 D6 D7 C0C1C2C3/S4D5D6D7 10 0x33 C0 C1 C2 C3 D5 D6 D7 O0D1D2D3/S4D5D6D7 10 0x66 D1 D2 D3 O0 D5 D6 D7 O0D1D2D3/O4D5D6D7 10 0x55 D1 D2 D3 O0 O4 D5 D6 D7 S0D1D2D3/D4D5D6D7 10 0x78 D1 D2 D3 D4 D5 D6 D7 O0D1D2D3/C4C5C6C7 10 0x4b D1 D2 D3 O0 C4 C5 C6 C7 T0C1C2C3/C4C5C6C7 10 0x87 C1 C2 C3 C4 C5 C6 C7 D0T1C2C3/C4C5C6C7 10 0x99 D0 C2 C3 C4 C5 C6 C7 D0D1T2C3/C4C5C6C7 10 0xaa D0 D1 C3 C4 C5 C6 C7 D0D1D2T3/C4C5C6C7 10 0xb4 D0 D1 D2 C4 C5 C6 C7 D0D1D2D3/T4C5C6C7 10 0xcc D0 D1 D2 D3 C5 C6 C7 D0D1D2D3/D4T5C6C7 10 0xd2 D0 D1 D2 D3 D4 C6 C7 D0D1D2D3/D4D5T6C7 10 0xe1 D0 D1 D2 D3 D4 D5 C7 D0D1D2D3/D4D5D6T7 10 0xff D0 D1 D2 D3 D4 D5 D6

64B/66B(also used for 10G FibreChannel)

110001 0100110001 1011000 0001103D3.0

010010 1011101101 0100000 0001002D2.0

100010 1011011101 0100000 0000101D1.0

011000 1011100111 0100000 0000000D0.0

Abcdei fghjAbcdei fghj

Current RD +Current RD-Octet BitsHGF EDCBA

Octet ValueCode Group name

8B/10B


What is GFP

• Generic Framing Procedure, defined by ITU-T G.7041. A data encapsulation technique for the transport of data over communications networks such as:

• SONET/SDH• OTN• RPR• PDH

• . Two types of frames• Client frames

• Client data frames (carry user payload)• Client management frames

• Control frames: Idle frames• Two types of mapping

• Frame-mapped GFP• Transparent-mapped GFP


GFP client frame structure

Octet transmission order

1

2

3

4

5

6

7

8

UPI

tHEC

tHEC

<7:00>

<15:08>

<7:00>

9

10

11

12

CID

Spare

eHEC

eHEC

<7:00>

<7:00>

<15:08>

<7:00>Payl

oad

head

ers

4-64

byt

es7 6 5 4 3 2 1 0

PTI PFI EXI

Bit number

Null extensionheader

Linear extensionheader

Cor

e h

eade

r4

Payl

oad

Area

FCS (CRC-32)

Optional payload

Field ( MAC )

Client payload information

eHEC

Extension header field

tHEC

Type

cHEC <7:00>

cHEC <15:08>

PLI <7:00>>

PLI <15:08>

• PLI & cHEC to provide frame sync. and delineation

• Ethernet frames contained in ‘client payload info field

• UPI to indicate payload type, e.g. Ethernet, RPR, …

• Allows multiple data streams to be transported over single path via the use of CID


Ethernet over digital wrapper-----OTU2

1 7 8 14 15 16 17 1904

1905

1920

1921

3824

3825

4080

1

2

3

4

FAOTU2 OH

ODU2 OHFEC

OP

U2

OH

Fixed Stuff

Bytes (for OC-

192/ STM-64

mapping)

Column (bytes)

Row

• Mapping 1: OTU2 With fixed stuff• OTU1 and OTU2 are part of the OTN family defined in ITU-T G.709

• Fixed frame format for all rates• Longer transmission distance

due to use of forward error correction

• Two types of mapping schemes, which one to use depends on the actual client signal

• Rich overhead capabilitiesOC-192

10 GE PCSGFPMAC

OTU2

10G MAC10 GE WAN

• Mapping 2: OTU2 Without fixed stuff

1 7 8 14 15 16 17 3824

3825

4080

1

2

3

4

FEC

OP

U2

OH

FAOTU2 OH

ODU2 OH

Column (bytes)

Row

GFPMAC

OTU2

…

1 GE

1 GE

OTU2


Ethernet over digital wrapper-----OTU1

WAN

OTU1

1 7 8 14 15 16 17

3824

3825

4080

1

2

3

4

FEC

OP

U1

OH

FAOTU1 OH

ODU1 OH

Column (bytes)

Row

OC-48GFPMAC

OTU1 GFPMAC


Transporting 10GE LAN with digital wrapper

• A technique to transparently transport 10GE LAN traffic• Frame structure and overhead definition is the same as for OTN• May be different on the use of overhead fields

Mapping 1: 11.095 Gbps Mapping 2: 11.049 Gbps

1 7 8 14 15 16 17 1904

1905

1920

1921

3824

3825

4080

1

2

3

4

FAOTU2 OH

ODU2 OHFEC

OP

U2

OH

Fixed Stuff

Bytes (for OC-

192/ STM-64

mapping)

Column (bytes)

Row

1 7 8 14 15 16 17

3824

3825

4080

1

2

3

4

FECO

PU

2 O

H

FAOTU2 OH

ODU2 OH

Column (bytes)

Row

10 GE LAN10 GE LAN 10 GE LAN

WAN10 GE LAN 10 GE LAN

11.049G or11.095G

11.049G or11.095G


Ethernet over PDH/SONET/SDH

WAN or MAN

N x DS1

Access Backbone Access

High speedoptical signal

DS3 …

…

10/100

10/100

SDH

E1 E3

GFP

MAC

…VCATN x E1

SONET

DS1 DS3

GFP

MAC

…VCAT

N x DS1

1GE

SONET/SDH

STS-1 SPE #1

… …

GFP

MAC

STS-1SPE #N

• When multiple DS1s/E1s already exist and no SONET/SDH connection available at customer premise, EoPDH is a quick and low cost solution. Use N x DS1 (VCAT) or DS3 to transport 10/100 Ethernet signal, N x STS-1 to transport 1GE,

• Virtual concatenation is key in such configuration


Virtual concatenation-----VCAT

An SDH example • Multiple channels to transport traffic with higher bandwidth than available on one single channel, each channel is transported independently

• 2-stage multi-frame to help recombine the traffic

• Sequence indicator identifies member number within one virtually concatenated group151111Sequence indicator SQ LSB (bits 5-

8)

140111Sequence indicator SQ MSB (bits 1-4)

131011Reserved ("0000")

120011Reserved ("0000")

111101Reserved ("0000")

100101Reserved ("0000")

91001Reserved ("0000")

80001Reserved ("0000")

71110Reserved ("0000")

60110Reserved ("0000")

51010Reserved ("0000")

40010Reserved ("0000")

31100Reserved ("0000")

20100Reserved ("0000")

110002nd multiframe indicator MFI2 LSB(bits 5-8)

n000002nd multiframe indicator MFI2 MSB(bits 1-4)

1st multiframe indicator MFI1 (bits 1-4)

Bit 8Bit 7Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1

2nd multi-frame numb

er

1st multi-frame numb

er

H4 byte

151111Sequence indicator SQ LSB (bits 5-8)

140111Sequence indicator SQ MSB (bits 1-4)

131011Reserved ("0000")

120011Reserved ("0000")

111101Reserved ("0000")

100101Reserved ("0000")

91001Reserved ("0000")

80001Reserved ("0000")

71110Reserved ("0000")

60110Reserved ("0000")

51010Reserved ("0000")

40010Reserved ("0000")

31100Reserved ("0000")

20100Reserved ("0000")

110002nd multiframe indicator MFI2 LSB(bits 5-8)

n000002nd multiframe indicator MFI2 MSB(bits 1-4)

1st multiframe indicator MFI1 (bits 1-4)

Bit 8Bit 7Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1

2nd multi-frame numb

er

1st multi-frame numb

er

H4 byte


Resilient packet ring ---------- RPR

• Specified in IEEE Std. 802.17----2004• MAC layer technology optimized for bandwidth

efficiency for data traffic in transport network• Dynamic bandwidth adjustment with fairness

control• Quick link failure recovery• Physical layer independent, can use

• SONET/SDH• Ethernet PHY

MAC client

MAC control

Fairness Topology andprotection OAM

MAC datapath

PRS-1 or PRS-10 GRS SRS

GFP HDLC-like adaptation

SONET/SDH PHY

PacketPHY

Medium

RPR

Medium


RPR frame structure----data frame

fcs4

serviceDataUnitn

protocolType2

saExtended6

daExtended6

hec2

ressopsfief

extendedControl1

ttlBase1

sa6

da6

pwescftferi

baseControl1

ttl1

Data FrameSize bytes • Other frames that have

been defined include•Fairness frames•Control frames and•Idle frames

• Client Ethernet data are carried in RPR data frames

Optional

802.3 MAC frame


Testing the optical transport of Ethernet

• Some techniques to transport Ethernet signals in the optical domain:– Native Ethernet:

• 1 GE • 10 GE

– In transport network• SONET/SDH• OTN• Non-standard digital wrapper• RPR

– In access network: EoPDH

• Testing of transport capabilities involves the test of every procedure that is involved

• Traffic handling capabilities involves other types of testing– RFC 2544: Throughput, latency, back-to-back frames, frame loss rate– Multiple streaming with variable address, VLAN, length, …


Testing 1GE and 10GE

• Coding: verify that transmission code is done properly. Receiverhandles invalid code based on the standards

• Payload BER• Alarm generation and detection

• Local fault• Remote fault

• Control information (ordered_set…)• PCS capturing reveals information not found on higher layer

Ethernet tester ( IFG, preamble, actual codegroup, ordered_set…)• PCS editing allows for conformance testing• Need full SONET testing to perform complete testing of 10GE WAN

110001 0100110001 1011000 0001103D3.0

010010 1011101101 0100000 0001002D2.0

100010 1011011101 0100000 0000101D1.0

011000 1011100111 0100000 0000000D0.0



Octet Value

Code Group name

110001 0100110001 1011000 0001103D3.0

010010 1011101101 0100000 0001002D2.0

100010 1011011101 0100000 0000101D1.0

011000 1011100111 0100000 0000000D0.0



Octet Value

Code Group nameReconciliation

PMA8B/10B PCS

Reconciliation

OC-192

64B/66B PCS

PMA PMA

8B/10B PCS

MAC

64B/66B PCS


Testing Ethernet over digital wrapper

• Mapping of Ethernet frames into GFP• GFP operations• Full SONET/SDH when applicable

• Framing• Mapping• Overhead (Alarm, pointer, APS, B1, B2, B3 …)• VCAT (when applicable)

• All that apply to 10GE LAN and WAN testing when applicable• Full Digital Wrapper testing ( OTN falls within the category of

digital wrapper)• Overhead• Alarm generation and detection, …)

• Payload BER• Overhead capturing and GFP capturing can be a useful tool

in development and trouble shooting

OC-19210 GE PCSGFP

MAC

OTU2

10G MAC

GFPMAC

OC-48GFPMAC

OTU1 GFPMAC

MAC

64B/66B PCS

Digital Wrapper

1 7 8 14 15 16 17 1904

1905

1920

1921

3824

3825

4080

1

2

3

4

FAOTU2 OH

ODU2 OHFEC

OP

U2

OH

Fixed Stuff

Bytes (for OC-

192/ STM-64

mapping)

Column (bytes)

Row

1 7 8 14 15 16 17

3824

3825

4080

1

2

3

4

FEC

OP

U2

OH

FAOTU2 OH

ODU2 OH

Column (bytes)

Row


Testing Ethernet over PDH/SDH/SONET

WAN or MAN

N x DS1

OC-1/3/12,…DS3 …

…

10/100

10/100

SONET/SDH

STS-1 SPE #1

… …

GFPMAC

• Mapping of Ethernet frames into GFP• GFP operations• Conventional PDH testing (DS1, DS3)• SONET/SDH testing (framing,

mapping, overhead, ...)• VCAT/LCAS testing• Payload BER

STS-1 SPE #N

SONET

DS1 DS3GFPMAC

VCATN x DS1

…


Testing Ethernet over RPR

fcs4

serviceDataUnitn

protocolType2

saExtended6

daExtended6

hec2

ressopsfief

extendedControl1

ttlBase1

sa6

da6

pwescftferi

baseControl1

ttl1

Data FrameSize bytes

fcs4

serviceDataUnitn

protocolType2

saExtended6

daExtended6

hec2

ressopsfief

extendedControl1

ttlBase1

sa6

da6

pwescftferi

baseControl1

ttl1

Data FrameSize bytes • Mapping/demapping of Ethernet frame into/out

RPR• RPR protocol testing (fairness, protection, …)• Mapping of RPR frame into/out GFP• GFP operations• Full SONET/SDH testing as previously

described• Frame capturing usefull in development and

trouble shooting

Logical link control (MAC client)

Fairness Topology andprotection OAM

RPRMAC datapath

PRS-1 or PRS-10 GRS SRS

GFP HDLC-like adaptation

SONET/SDH PHY

PacketPHY


Summary

We have discussed about techniques to transport Ethernet signals in the optical domain:

• Native Ethernet: •1 GE •10 GE

• EoPDH/SONET/SDH• OTN (OTU2/OTU1)• Non-standard digital wrapper (11.049G, 11.095G with

FEC) , and• RPR

Testing of transport capabilities involves the test of every procedure that leads to the final format.Data capturing is a powerful tool for analysisGFP capturing is often Key in many cases


Questions and answers

Copyright Innocor Ltd. www.innocor.com

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Transporting Ethernet