SDH Marconi

Training Document SDH1

SDHSynchronous Digital Hierarchy


WHAT is SDH ?•Background and motivation for SDH•Limitation of today’s high capacity network•Advantages of SDH


Definition of SDHSDH is stands for

Synchronous Digital Hierarchyand is :

•An International Standard for a high capacity optical telecommunication network

•A synchronous digital transport system aimed at providing a more simple, economical, and flexible telecommunications network infrastructure.


Changing Network Requirements

TODAY TOMORROW

POINT TO POINTTRANSMISSION

TELECOMMUNICATIONNETWORKING

SUPPORTED BY SUPPORTED BY

MANUAL APPROACHTO NETWORK MANAGEMENT

AND MAINTENANCE

COMPUTER-BASEDINTEGRATED NETWORK

MANAGEMENT AND MAINTENANCE

FASTER PROVISIONING OFCIRCUITS AND SERVICES

CUSTOMER NEEDS


PDH Systems Worldwide

2048 kbit/s

64 kbit/s

x 4

x 30/31x 24

x 3

x 7x 5

x 3

Japan USA-ANSI

Europe -ETSI

primary rate

.

.

.

32064 kbit/s

x 3

97728 kbit/s

397200 kbit/s

x 4

x 4

34368 kbit/s

139264 kbit/s

x 4

564992 kbit/s

x 4

8448 kbit/s

44736 kbit/s

274176 kbit/s

x 6

1544 kbit/s

6312 kbit/s

x 4


Limitations of Today’s High Capacity Network

• Inflexible, and expensive for telecommunication networking -based on step-by-step asynchronous multiplexing

•Extremely limited network management and maintenance support capabilities - no spare signal capacity in plesiochronous frame structures

• Higher rate line systems are proprietary. -no possibility of inter-working

2/88/34

34/140MUX

2 Mbit/s channels

2/88/34

34/140MUX

2 Mbit/s channels

2/88/34

34/140MUX

2/88/34

34/140MUX

2 Mbit/s channels

140Mbit/s 140Mbit/s


Advantages of SDH ( I )• Designed for cost effective, simplified add & drop Function - Compared to the older PDH system, low bit rate channels can be easily extracted from and inserted into the high-speed bit streams in SDH. It is now no longer necessary to apply the complex and costly procedure of demultiplexing then re-multiplexing the plesiosynchronous structure.

140 Mbit/s

34 Mbit/s

2 Mbit/s

STM-1

FDDI

ATM

STM-N

• Reliability -Modern SDH networks include various automatic back-up circuit and repair mechanisms which are designed to cope with system faults and are monitored by management. As a result, failure of a link or an NE does not lead to failure of the entire network.


Advantages of SDH ( II )• High Transmission rates -Transmission rates of up to 10Gbps can be achieved in modern SDH systems making it the most suitable technology for backbones-the superhighways in today’s telecommunication networks.

10 Gbit/s

155 Mbit/s

622 Mbit/s

2.5 Gbit/s

STM-1 STM-16 STM-64STM-4• Future-proof platform for new services -SDH is the ideal platform for a wide range of services including POTS, ISDN, mobile radio, and data communications (LAN, WAN, etc.). It is also able to handle more recent services such as video on demand and digital video broadcasting via ATM.


Advantages of SDH ( III )

• Interconnection -SDH makes it much easier to set up gateways between different network providers and to SONET systems. The SDH interfaces are globally standardized, making it possible to combine NEs from different manufacturers into a single network thus reducing equipment costs. -The trend in transport networks is toward ever-higher bit rates, such as STM-256 (time division multiplex, TDM). The current high costs of such NEs however are a restricting factor. The alternative lies in dense wavelength division multiplexing (DWDM), a technology enabling the multiple use of single mode optical fibers. As a result, a number of wavelengths can be used as carriers for the digital signals and transmitted simultaneously through the fibers.

• Provide built-in signal capacity for advanced network management and maintenance capabilities -With SDH, network providers can react quickly and easily to the requirements of their customers. For example, leased lines can be switched in a matter of minutes. The network provider can use standardized network elements (NE) that can be controlled and monitored from a central location via a telecommunications management network (TMN) system.


Synchronous Network Structure

2Mbit/s 34Mbit/s 140Mbit/s STM-1 STM-4

STM-1 / STS-3c Gateway to SONET

TM

DXC

ADMADM ATMSwitch

STM-4/162Mbit/s

34Mbit/s

140Mbit/s

STM-1

LAN

2Mbit/s

ADM

STM-1

STM-1, STM-4

2Mbit/s

8Mbit/s34Mbit/s

140Mbit/s

ADM : Add Drop MultiplexerDXC : Digital Cross ConnectTM : Terminal MultiplexerDSC: Digital Switching CenterLAN: Local Area Network

DSC


STM-1 Frame Structure


STM-1 Frame

270 columns9 rows

capacity:270 bytes x 9= 2430 Bytes

frame length:125 µs

Pointer

RSOH

MSOH

1 91

9

9 lines Payload

270 bytes

0 125 µs


Frame Structure of the STM-1 Signal

• SOH Area– operational functions– monitoring functions

– control functions

• AU-Pointer– shows the beginning of the virtual

container of the highest level

• Payload Area– transport of the data

270 bytes

Pointer

RSOH

MSOH

1 91

9

9 li

nes

Payload

0 125 µs


Functions and characteristics of the Section Overhead (SOH)

• includes operation, monitoring and controlling functions

• each byte is equivalent to an 64-kbit/s channel• in regenerators only the first three lines are

accessable• in multiplexers the last five lines are accessable• preserves the connections from the point of creation

until the point of decomposition

Pointer

RSOH

MSOH

1 91

9

9 li

nes

Payload

0 125 µs

270 bytes


Structure of the RSOH Frame Alignment

(A1, A2)

Section Trace (J0 Identfication of regenerator source)

Parity check(B1 calculated by regenerator and multiplexers)

Data communication channels(D1...D3, F1 between regenerators)

Voice communication channels(E1 between regenerators)

B1 E1

D1 D2

D4

D7

D5

D8

S1 Z1 Z1 Z2 Z2 M1 E2

D9

D6

K2

D3

F1

A2 J0A1 A1 A1 A2 A2

B2 B2 B2 K1

H3H1 H3 H3H2

D10 D11 D12

RSOH

MSOH

AU pointer

9

9

1

1


Structure of the MSOH

Automatic protection switching (K1, K2 Bytes)

Data communication channels (D4 to D12 between multiplexers)

Clock source information (S1)

Remote Error Indication (M1)

Voice communications channels (E2 between multiplexers)

Parity Check (B2)

B1 E1

D1 D2

D4

D7

D5

D8

S1 Z1 Z1 Z2 Z2 M1 E2

D9

D6

K2

D3

F1

A2 J0A1 A1 A1 A2 A2

B2 B2 B2 K1

H3H1 H3 H3H2

D10 D11 D12

RSOH

MSOH

AU pointer

9

9

1

1


STM-1 FRAME(to ITU-T

G.707)270 COLUMS(BYTES)

AU POINTER

MSOH

RSOH

C-4 (DATA PAYLOAD)

261 COLUMS(BYTES)1 9

Payload Areatransport of the data

AU-Pointer– shows the beginning of the

virtual container of the highest level

PATH OVERHEAD (POH)


STM-1 FRAME(to ITU-T

G.707)270 COLUMS(BYTES)

AU POINTER

MSOH

RSOH

C-4 (DATA PAYLOAD)

261 COLUMS(BYTES)1 9

260 COLUMS(BYTES)

Low RateTributary

Signal

VC PathOverHead

TUPointer

ContainerVirtual container

Low Order POH

Tributary SignalTributary Unit Frame


Structure of the POH

B3

C2

H4

F3

N1

J1

F2

G1

K3

POH

9

1

VC-4/ VC-3 POH

J2

N2

V5

K4

VC-12/ VC-11 POH

Parity check B3, V5/ BIP-2 calculat by path terminating point.

Alarm and performance information (V5, G1)

Signal label C2/V5

Multiframe indication for TUs (H4)

User communications channel between path elements (F2, F3)

Identification of the Path Source (Path Trace J1, J2)

Higher order path automatic protection switching.(K3,K4)

Tandem Connection monitoring (TCM) function. (N1,N2)

HO-POHHO-POH LO-POHLO-POH


Functions and characteristics of the Path Overhead (POH)

• includes path trace identifier, alarm signals and operational signals

• secures the transport of a container to the desired destination

Pointer

RSOH

MSOH

1 91

9

9 lin

es

Payload

0 125 µs

PO

H

270bytes


SynchronousMultiplexer

SynchronousMultiplexer

MultiplexerSection

MultiplexerSection

RegeneratorSection

Regenerator

Section

RegeneratorSection

RegeneratorSection

Path Section

SDH Network Section


SDH POINTERS


Difference between PDH and SDHtransport techniques

technique with frame memory (PDH)

technique with pointer processing (SDH)

Signal4

Signal1

Signal2

Signal3

transportoverhead

t = 0

t=T

t = 0

transportoverhead

t=T


Signal Processing

PointerPointerPayload

POH

VC-nSOH

VC - Virtual ContainerPOH - Path OverheadSOH - Section Overhead

STM-1 Signal


Why do we needpointer actions?

• neighbouring network elements (NEs) may have different bitrates

• in one NE the frequency of input fin may differ from the output fout

Pointer

RSOH

MSOH

1 91

9

9 li

nes

Payload

0 125 µs

PO

H

270bytes


Tasks of the Pointer• the pointer shows the begin of the Virtual

Container within the higher structure• adaptation of the bitrate of the VC to the

velocity of the tranport channel (AU, TU)• a flag within the pointer signals the

changes made• kind of stuffing will be signalized also

PointerPointerPayload

POHVC-nSOH

STM-1 Signal


AU4-PointerAU4-Pointer:

- Bytes H1, H2, H3- Byte H3 includes don’t care informationRange:0 <= X <= 782fin < foutpositive justification:- add three bytes behind H3- new pointer value = old pointer value + 1 - the new pointer value will be fixed for at least two STM-1 frames

H1H2H3

H1H2H3

VC-4

STM-1

STM-1

PointerPointer

begin of the VC-4


AU4-Pointer

AU4-Pointer:

fin > fout

negative justification:

- fill H3 with payload information- new pointer value = old pointer value - 1- the new pointer value will be fixed for at least two STM-1 frames

H1H2H3

H1H2H3

VC-4

STM-1

STM-1

H1H2H3STM-1

VC-4


SDH Multiplexing Structure and Frame Format


Mapping In SDH


Multiplexing Elements

virtual container

container

administration unit

synchronous transport module N

synchronous transport module

tributary unit group

tributary unit

POH

PTR

PTR

SOH

C-n n=1,2,3,4 bitratesG.702

VC-n m=1,2 C1, C2 n=3,4 C3, C4

TU-n n=1,2,3,4 VC-n

TUG-2 TU-1, -2

AU-n n=3,4 VC-n

STM-1 AU-n, n=3,4

STM-n N=4,16 AU-n, n=3,4

element abbreviation payload


SDH Multiplexing / Mapping for 2Mbit/s.


R: Fixed Stuff Bits

D: Data-Bits (of 2Mb/s Tributary-Signal)

O: Overhead-Bits (For future use)

C1, C2: Justification Indication-Bits-C1 = ‘0’ -> S1 = Data-Bit-C1 = ‘1’ -> S1 = Stuff-Bit-C2 = ‘0’ -> S2 = Data-Bit-C2 = ‘1’ -> S2 = Stuff-Bit

S1, S2: Actual Justification-Bits-Justification is indicated by C1, C2(Majority-Vote out of 3)

Justification –Capacity+/- 1 Bit every 500 µs -> +/- 2000 Bits (~+/- 1000 ppm)

Speed of C-12Speed of C-12136 Byte x 8 Bit / 500 136 Byte x 8 Bit / 500 µµs = 2.176 MBit/ss = 2.176 MBit/s

Container C-12 (Asynchronous Mapping for 2 MBit/s)

R R R R R R R RD D D D . . . .

. . . . D D D D

. . 256 x D . .

C1 C2 O O O R R R

R R R R R R R R

D D D D . . . .

. . . . D D D D

. . 256 x D . .

C1 C2 O O O R R R

R R R R R R R R

D D D D . . . .

. . . . D D D D

. . 256 x D . .

C1 C2 O O O R R S1

R R R R R R R R

S2 D D D D . . .

. . . . D D D D

. . 255 x D . .

R R R R R R R R

Blo

ck 1

Blo

ck 2

Blo

ck 3

Blo

ck 4

136

Byt

es (

500

µs)

1 Byte

STM-N AUG AU-4 VC-4 TUG-3 TUG-2 TU-12 VC-12 C-12 2Mbit/s


SDH Multiplexing Elements -(Container (C

• basic unit for tributary signals of the PDH• synchronous to the STM-1 signal• adaptation of bitrates through positive stuffing

in case of plesiochronous tributary signals• adaptation of synchronous tributaries through

fixed stuffing bits• bit stuffing mechanism


Virtual Container VC-12 / Mapping of C-12 into VC-12

V5

140

Byt

es

(500

µs)

1 Byte

J2

N2

K4

#1

#2

#35

#36

#37

#70

#71

#72

#105

#106

#107

#140

C-12

Block 1

C-12

Block 2

C-12

Block 3

C-12

Block 4

BIP-2 REI RFI Signal Label RDI

BIP-2: Bit Interleaved Parity 2

REI: Remote Error Indication (Old name FEBE)

RFI: Remote Failure Indication

Signal Label: Specifies the content of the VC

RDI: Remote Defect Indication (Old name=FERF)

J2: Repetitively transmitted 16-Byte Framecontaining a Path Access Point Identifier

N2: Used for Tandem Connection Monitoring

K4: APS-Channel: Automatic Protection Switching Signaling

Spare: For Future use

Speed of VC-12: 140 Byte x 8 Bit/500 Speed of VC-12: 140 Byte x 8 Bit/500 µµs= 2.240 Mbit/ss= 2.240 Mbit/s

Network Operator Byte N2

APS Channel Spare

Path Trace J2



SDH Multiplexing Elements -Virtual Container- VC

• creation through addition of the POH

• is transported through the network as one unit

• if the VC contains several VCs, it will have a pointer area

• multi container payload through concatenation

VC-12VC-12

41

9


N N N N S S P P

V1 (TU-Pointer #1)

144

Byt

es

(500

µs)

V1+V2 N: New Data Flag (NDF) -Flag NOT active -> NNNN = ‘0110’ -Flag active -> NNNN = ‘1001’ (Inverted)

S: Size Indication -For TU-12 SS=’10’

P: 10-Bit Pointer Value -Range for TU-12 is 0….139 -Points to that Cell, Where the VC-12 starts (Location of V5)

V3 Used for justification -Incase of Negative Pointer Justification, this Byte is used as Auxiliary-Cell

V4 Reserved (For future Use)

Tributary Unit TU-12

V2 (TU-Pointer #2)

Cell #105

Cells #106… #138

Cell #139

Cells #1… #33

Cell #0

V3 (TU-Pointer #3)Cell #34

Cell #35

V4 (TU-Pointer #4)Cell #69

Cell #70

Cells #36… #68

Cells #71… #103

Cell #104 Speed of TU-12: 144 Byte x 8 Bit/500 Speed of TU-12: 144 Byte x 8 Bit/500 µµs= 2.304 Mbit/ss= 2.304 Mbit/s

P P P P P P P P



Important Facts:

–The TU-12 must be locked to the Higher-Order VC (VC-3 or VC-4)

–The 10-Bit TU-Pointer points to that cell, where the V5-Byte Of the VC-12 is located (Start of VC-12)

–The VC-12 can float within the TU-12 since both may have Different Clock rates

– If the incoming VC-12 is too fast, the excess data is carried By V3. The V5-Byte moves 1 cell up in the TU-12 and the pointer value decrements by 1-> Negative Pointer Justification

– If the incoming VC-12 is too slow, the byte immediately after V3 (Cell #35) is used as Stuff-Byte to stuff the excess transport capacity of the TU-12. The V5-byte moves 1 cell down in the TU-12 and the pointer value increments by 1.-> Positive Pointer Justification

Mapping of VC-12 into TU-12

V1

V2

V3

V4

VC

-12

35 Byte

35 Byte

35 Byte

35 Byte


Under normal conditions the pointer is justified by 1 (Increase or Decreaseas soon as the phase different between the VC-12 and TU-12 exceeds8 Bits (1Byte). This is Indicated by inverting either the I or the D Bits of the10-Bit Pointer (Majority vote out of 5). If a random change of the pointer value becomes necessary, this is indicated by activating (inverting) the new Data Flag.

Pointer Justification on TU-12 Level

0 1 1 0 1 0 I D I D I D I D I D

Speed of TU-12:144 Byte x 8 Bit/500 µs= 2.304 Mbit/s

V1 V2V1

V2

Cell #105

Cell #139

Cell #0

V3Cell #34

Cell #35

Cell #69

Cell #70

Cell #104

V4

Inverted value of all D-Bits (Decrease)Indicates Negative JustificationInverted value of all I-Bits (Increase)Indicates Positive JustificationNegative Justification Opportunity

(Used to carry Data)

Positive Justification Opportunity(Used as Stuff-Byte)

New Data FlagSize


SDH Multiplexing Elements - Tributary Unit - TU

• creation through addition of a pointer to the VC

• slip free transmission of a VC also in case of plesiochronous behaviour of the network element

• the TU definition refers to the VC, the AU to STM-1

• identical to AU TU-12

Pointer

9

4

V5

2 Mbit/s 2 Mbit/s

--> C-12--> C-12

VC-12 POHVC-12 POH

41

1


Byte Interleaved Multiplexing of 3 x TU-12 into TUG-2 Multiframe

V1, 1

V2, 1

#105, 1

#139,1

#0, 1

V3, 1#139, 1

#35, 1

#69, 1

#70, 1

#104, 1

V4, 1

V1, 2

V2, 2

#105, 2

#139,2

#0, 2

V3, 2#139, 2

#35, 2

#69, 2

#70, 2

#104, 2

V4, 2

TU-12 #1 TU-12 #2 TU-12 #3

V1, 3

V2, 3

#105, 3

#139,3

#0, 3

V3, 3#139, 3

#35, 3

#69, 3

#70, 3

#104, 3

V4, 3

Column 1 2 3 4 5 6 7 8 9 10 11 12

V1,1 V1,2 V1,3 #105,1 #105,2 #105,3

#139,1 #139,2 #139,3

V2,1 V2,2 V2,3 #0,1 #0,2 #0,3

#34,1 #34,2 #34,3

V3,1 V3,2 V3,3 #35,1 #35,2 #35,3

#69,1 #69,2 #69,3

V4,1 V4,2 V4,3 #70,1 #70,2 #70,3

#104,1 #104,2 #104,3

TUG-2 multiframe

125

µs1

25 µ

s12

5 µs

125

µs



1 2 3 4 5 6 7 8 9 10 11 12

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

Column

TUG-2 #1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 2476 77 78 79 80 81 82 83 84 85 86


Column

NP

IT

UG

-3 S

TU

FF

TU

G-3

ST

UF

F

1 2 3


Column

TUG-2 #212 1 2 3


Column

TUG-2 #312 1 2 3


Column

TUG-2 #712

Byte Interleaved Multiplexing of 7 x TUG-2 into 1 TUG-3

1--------------------------8

Row 1Row 2Row 3

Bit

NPI

1 0 0 1 X X 1 1

1 1 1 0 0 0 0 0

X X X X X X X X

TUG-3



1 2 3 4 5 6


Column

TUG-3 #284 85 86

TU

G-3

# 2

ST

UF

F

TU

G-3

# 2

ST

UF

FNP

I

1 2 3 4 5 6


Column

TUG-3 #384 85 86

TU

G-3

# 2

ST

UF

F

TU

G-3

# 2

ST

UF

FNP

I

1 2 3 4 5 6


Column

TUG-3 #184 85 86

TU

G-3

# 2

ST

UF

F

TU

G-3

# 2

ST

UF

FNP

I

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 251 252 253 254 255 256 257 258 259 260 261


Column

NP

I #1

VC

-4 P

ath

OH

VC

-4 S

tuff

Byte Interleaved Multiplexing of 3 x TUG-3 (Containing TUG-2s) into VC-4

NP

I #2

NP

I #3

TU

G-3

# 1

ST

UF

F

TU

G-3

# 2

ST

UF

F

TU

G-3

# 3

ST

UF

F

VC

-4 S

tuff

TU

G-3

# 1

ST

UF

F

TU

G-3

# 2

ST

UF

F

TU

G-3

# 3

ST

UF

F

VC-4



SDH Multiplexing Elements - Tributary Unit Group - TUG

• multiplexing of several TUs into a VC

• identical to AUG


Administrative Unit AU-41 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 2

64

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column 265

266

267

268

269

270

#522

#609

#696

#0

#87

#174

#261

#348

#435

#523

#610

#697

#1

#88

#175

#262

#349

#524

#611

#698

#2

#89

#176

#263

#350

#607

#694

#781

#85

#172

#259

#346

#433

#608

#695

#782

#86

#173

#260

#347

#434

#436 #437 #520 #521

H1 Y Y H2 1* 1* H3 H3 H3

AU-4Payload

N N N N S S P P P P P P P P P P

AU-4 Pointer

H1+H2 N: New Data Flag (NDF) -Flag NOT active -> NNNN = ‘0110’ -Flag active -> NNNN = ‘1001’ (Inverted)

S: Size Indication -Not Specified on AU-4 Level (Don’t care Bits)

P: 10-Bit Pointer Value -Range for TU-12 is 0….728 -Points to that Cell, Where the VC-4 starts

Y-Bytes: Stuff Byte (Value=93 hex)-Used as “H1” in AU-3 Pointer

1*-Bytes: Stuff Byte (Value=FF hex)-Used as “H2” in AU-3 Pointer

H3-Bytes: Used for justification- Incase of Negative pointerjustification, these bytes areused as Auxiliary-Cells



Pointer Justification on AU-4 Level

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column

H1 Y Y H2 1* 1* H3 H3 H3

0 1 1 0 1 0 I D I D I D I D I D

H1 H2

Inverted value of all D-Bits (Decrease)Indicates Negative Justification

Inverted value of all I-Bits (Increase)Indicates Positive Justification

New Data Flag Size

Under normal conditions the pointer is justified by 1 (Increase or Decrease) as soon as The phase different between the VC-4 and AU-4 exceeds (3 Byte). This is Indicated by inverting either the I- or the D-Bits of the 10-Bit Pointer (Majority vote out of 5) If a random change of the pointer value becomes necessary, this is indicated by activating (inverting the new Data Flag

Negative Justification Opportunity(Used to carry Data)



Administrative Unit Group AUG

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column

Capacity of AUG: 1 x AU-4 (European standard)

Payload

AU-Pointer(s)

267

268

269 270



SDH Multiplexing Elements - Administrative Unit Group - AUG

• multiplexing of several AUs into a STM-N


D E F GBA

GFEDCBAGFEDCBAGFEDCBA

C

a b c

TUG

TU POINTER

TU

VCC

PLESIOCHRONOUSSTREAM

STUFF ANDJUSTIFICATION BITS

PATHOVERHEAD

a b c

HIGHER LEVEL VC

AU

STM-1

ADMINISTRATIVEUNIT (AU)POINTERS

SOH

POH

SOH = SECTION OVERHEAD

VC = VRITUAL CONTAINER

POH = PATH OVERHEAD

TUG = TRIBUTARY UNIT GROUP

9 Byte 261 Bytes

9 B

ytes

STRUCTURE OF STM-1

FRAME


How to integrate plesiochronous signals?into the synchronous transport module

synchronoustransport module

administrationunit

virtualcontainer

container

Path Overhead

Pointer

Section Overhead

plesiochronousSignal (140Mbit/s)

VC-4

AU-4/ AUG1

STM-1

C-4


Asynchronous Mapping for 140 MBit/s into C-4

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

D C R R R C R R R C R R R C R R R C R C

260 Bytes

13 Bytes

Note: Only 1 of 9 Subframes is shown (1 Subframe=20 Blocks = 1 Row of a C-4)

Block

R: Fixed Stuff Bits

D: Data-Bits (of 140Mb/s Tributary-Signal)


C: Justification Indication-Bits C = ‘0’ -> S = Data-Bit C = ‘1’ -> S = Stuff-Bit

S: Actual Justification-Bits Justification is indicated by C-Bits (Majority-Vote out of 5)

D D D D D D D D D D D . . . 96 x D . . . D D D

Byte 1 Byte 2……13

D-Block

C-Block

R-Block

C R R R R R O O D D D . . . 96 x D

R R R R R R R R D D D . . . 96 x D

D D D D D D S R D D D . . . 96 x D

. . . D D D

. . . D D D

. . . D D D S-Block


Virtual Container VC-4 (C-4 Structure)

1 2 3 4 5 6 7 8

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column

Speed of VC-4261 x 9 Byte x 8 Bit / 125 µs = 150.336 MBit/s

C4

259

260

261

J1

B3

C2

G1

F2

H4

F3

K3

N1

VC-4 Path Overhead (Higher Order POH)

STM-N AUG AU-4 VC-4 C-4


Administrative Unit AU-41 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 2

64

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column 265

266

267

268

269

270

#522

#609

#696

#0

#87

#174

#261

#348

#435

#523

#610

#697

#1

#88

#175

#262

#349

#524

#611

#698

#2

#89

#176

#263

#350

#607

#694

#781

#85

#172

#259

#346

#433

#608

#695

#782

#86

#173

#260

#347

#434

#436 #437 #520 #521

H1 Y Y H2 1* 1* H3 H3 H3

AU-4Payload


AU-4 Pointer


S: Size Indication -Not Specified on AU-4 Level (Don’t care Bits)

P: 10-Bit Pointer Value -Range for TU-12 is 0….728 -Points to that Cell, Where the VC-4 starts

Y-Bytes: Stuff Byte (Value=93 hex)-Used as “H1” in AU-3 Pointer

1*-Bytes: Stuff Byte (Value=FF hex)-Used as “H2” in AU-3 Pointer

H3-Bytes: Used for justification- Incase of Negative pointerjustification, these bytes areused as Auxiliary-Cells

STM-N AUG AU-4 VC-4 C-4


STM#1

AU-4VC-4

C-4

Payload

POH

AU-PTR

R-SOH

M-SOH

AU Administrative UnitVC Virtual ContainerC Container

270 Bytes9 1

3

1

5

STM-1 Frame


Asynchronous Mapping for 34 MBit/s into C-3

R R R R

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

R R R R

R R R R

R R R R R C R R R R R R R R R C

R R R R R C R R R R R R R R R C

R R R R R C R R R R R R R R R S

84 Bytes

4 Bytes 1 Byte

Note: Only 1 of 3 Subframes (3 Rows) are shown

Block

Blks 21….40

Blks 41….60

R: Fixed Stuff Bits

D: Data-Bits (of 34Mb/s Tributary-Signal


C1, C2: Justification Indication-Bits Cx = ‘0’ -> Sx = Data-Bit Cx = ‘1’ -> Sx = Stuff-Bit

S1, S2: Actual Justification-Bits Justification is indicated by C1, C2-Bits (Majority-Vote out of 5)

R R R R R R R R D D D . . . 24 x D . . . D D D

Byte 1 Byte 2 Byte 3 Byte 4

R-Block

R R R R R R C1C2 D D D . . . 24 x DC-Block

R R R R R R R RS-Block

R R R R R R R R-Block

. . . D D D

D D D D D D D DR R R R R R R S1 S2 D D D D D D D


Virtual Container VC-3

1 2 3 4 5 6 7 8

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column

Speed of VC-385 x 9 Byte x 8 Bit / 125 µs = 48.960 MBit/s

C3

83 84 85

J1

B3

C2

G1

F2

H4

F3

K3

N1

VC-3 Path Overhead (Lower Order POH)

STM-N AUG AU-4 VC-4 TUG-3 TU-3 VC-3 C-3 34M




S: Size Indication -Not Specified on TU-3 Level (Don’t care Bits)

P: 10-Bit Pointer Value -Range for TU-3 is 0….764 -Points to that Cell, Where the VC-3 starts (Location of J1)

H3-Bytes: Used for justification- Incase of Negative pointerjustification, these bytes are used as Auxiliary-Cell.

Tributary Unit TU-3

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

1 2 3 4 5 6 7 8 9Column

TU-3Payload

83 84 85

H1

H2

H3

Fix

ed S

tuff

TU-3 Pointer

82

86


Pointer Justification on TU-3 Level

0 1 1 0 1 0 I D I D I D I D I D

H1 H2

Inverted value of all D-Bits (Decrease)Indicates Negative Justification

Inverted value of all I-Bits (Increase)Indicates Positive Justification

New Data Flag Size

Under normal conditions the pointer is justified by 1 (Increase or Decreases soon as The phase different between the VC-3 and TU-3 exceeds 1Byte. This is Indicated by inverting either the I- or the D-Bits of the 10-Bit Pointer (Majority vote out of 5)If a random change of the pointer value becomes necessary, this is indicated by activating (inverting the new Data Flag

1 2 3 4 5 6

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column 85

H1

H2

H3

Fix

ed S

tuff

86


Negative Justification Opportunity(Used to carry Data)



Tributary Unit Group TUG-3 (TU-3 Structure)

1 2 3 4 5 6 7 8

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Row 7

Row 8

Row 9

Column 85

TU

-Poi

nte

r

86

Speed of TUG-385 x 9 Byte x 8 Bit / 125 µs = 48.960 MBit/s

84

TUG-3Payload



1 2 3 4 5 6


Column

TUG-3 #284 85 86

TU

G-3

# 2

ST

UF

F

TU

G-3

# 2

ST

UF

F

1 2 3 4 5 6


Column

TUG-3 #384 85 86

TU

G-3

# 2

ST

UF

F

TU

G-3

# 2

ST

UF

F

1 2 3 4 5 6


Column

TUG-3 #184 85 86

TU

G-3

# 2

ST

UF

F

TU

G-3

# 2

ST

UF

F

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 251 252 253 254 255 256 257 258 259 260 261


Column

Byte Interleaved Multiplexing of 3 x TUG-3 (Containing TUG-3s) into VC-4

VC-4

H1

H2

H3

H1

H2

H3

H1

H2

H3

VC

-4 P

ath

OH

VC

-4 S

tuff

VC

-4 S

tuff

TU

G-3

# 1

ST

UF

F

TU

G-3

# 2

ST

UF

F

TU

G-3

# 3

ST

UF

F

H1

H2

H3

H1

H2

H3

H1

H2

H3



STM-1 Multiplexing and Pointer Structure

J1

RSOHRSOH

AU-4 PointerAU-4 Pointer

MSOHMSOHV

C-4

PO

HJ1

PO

HV

C-3

TU-3Pointer

TU-2Pointer

TU-12Pointer

NPI R

R R

1

9

9

9

9

9

9

9

9

2709

261

86

85

86

12124

STM-1STM-1

VC-4VC-4

TU-3TU-3

VC-3VC-3

TUG-3TUG-3

TU-2TU-2

VC-12VC-12(VC-11)(VC-11)

VC-2VC-2

TUG-2TUG-2TU-12TU-12

34 Mbit/s, 45 Mbit/s --> C-334 Mbit/s, 45 Mbit/s --> C-3

140 Mbit/s --> C-4140 Mbit/s --> C-4

V5

2 Mbit/s 2 Mbit/s --> C-12--> C-12

VC-12 POHVC-12 POH

V5

6 Mbit/s --> C-26 Mbit/s --> C-2

VC-2 POH 12

4

R


STM-1 Signals as Transport Pipe

A STM-1 Signal Can Transport:

• One 140 Mbit/s PDH Signal

• Three 34 Mbit/s PDH Signals

• Sixty-three 2 Mbit/s PDH Signals

• Combinations, eg. twenty-one 2 Mbit/s and Two 34 Mbit/s PDH Signals

• ATM cells, FDDI, DQDB Protocols, etc.


SynchronousByte-interleavedmultiplexing


Error and Alarm Monitoring


Error and Alarm monitoring


Anomalies and defects in SDH

SDH Anomalies/Defects Detection criteria OH Byte

LOS Loss of signal Drop in incoming optical power level causes high bit error rate

OOF Out of frame A1, A2 errored for ≥ 625 µs A1,A2

LOF Loss of frame If OOF persists for ≥ 3 ms A1,A2

RS BIP Regenerator Section BIP Mismatch of the recovered B1Error Error (B1) and computed BIP-8 covers

the whole STM-N frame

RS-TIM Regenerator Section Mismatch of the accepted J0 Trace Identifier Mismatch and expected Trace Identifier in byte J0




MS BIP Error Multiplex Section BIP Mismatch of the recovered B2 Error (B2) and computed N x BIP-24

covers the whole frame except RSOH

MS-AIS Multiplex Section K2 (bits 6, 7, 8) = 111 K2 Alarm Indication Signal for ≥ 3 frames

MS-REI Multiplex Section Number of detected B2 M1 Remote Error Indication errors in the sink

side encoded in byte M1 of the source side.

MS-RDI Multiplex Section K2 (bits 6, 7 8) = 111 for K2 Remote Defect Indication ≥ z frames

(z = 3 to 5)




AU-AIS Administrative Unit All ones in the AU pointer H1, H2 Alarm Indication Signal bytes H1 and H2

AU-LOP Administrative Unit 8 to 10 NDF enable 8 to 10 H1, H2 Loss of Pointer invalid pointers

HP BIP Error HO Path BIP Error (B3) Mismatch of the recovered B3 and computed BIP-8 covers entire VC-n

HP-UNEQ HO Path Unequipped C2 = 0 for ≥ 5 frames C2

HP-TIM HO Path Trace Identifier Mismatch of the accepted J1 Mismatch and expected Trace Identifier in byte J1


HP-REI HO Path Number of detected B3 G1 Remote Error Indication errors in the sink side encoded in byte G1 (bits 1, 2, 3, 4) of the source side.

HP-RDI HO Path G1 (bit 5) = 1 for ≥ z G1 Remote Defect Indication frames (z = 3, 5 or 10)

HP-PLM HO Path Mismatch of the accepted C2 Payload Label Mismatch and expected Payload Label in byte C2

TU-LOM Loss of Multiframe H4 (bits 7, 8) multiframe H4 X = 1 to 5 ms not recovered for X ms

TU-AIS Tributary Unit All ones in the TU pointer V1-V4 Alarm Indication Signal bytes V1 and V2






TU-LOP Tributary Unit 8 to 10 NDF enable 8 to 10 V1,V2 Loss of Pointer invalid pointers

LP BIP Error LO Path BIP Error Mismatch of the recovered V5 and computed BIP-8 (B3) or BIP-2 (V5 bits 1, 2)

covers entire VC-n.

LP-UNEQ LO Path Unequipped VC-3: C2 = 0 for ≥ 5 frames V5 frames VC-m (m = 2, 11,

12): V5 (bits 5, 6, 7) = 000 for ≥ 5 multiframes

LP-TIM LO Path Trace Mismatch of the accepted V5 Identifier Mismatch and expected Trace Identifier in byte J1

(VC-3) or J2

SDH Marconi

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Transcript of SDH Marconi