Sdh Multiplexing

ALTTC TX-I/SDH/MUX 1

SDH MULTIPLEXING

BYTX-I FACULTYALTTC, GZB.


BASIC PHILOSOPHY

• MULTIPLEXING IS REQUIRED TO TRANSMIT

SO MANY INFORMATION ON THE SAME

PATH.

• SO IN CASE OF SDH MULTIPLEXING TIME

REMAINS THE SAME IN WHICH WE CAN

TRANSMIT THE INFORMATION OF SO MANY

CHANNELS BY WAY OF INTERLEAVING

METHOD.


DEFINITION OF DIFFERENT TERMINOLOGY

• STM- IT IS THE FINAL INFORMATION STRUCTURE

WHICH IS TO BE SUPERIMPOSED OVER THE LASER

FOR TRANSMISSION TO DISTANT END.

• IT IS THE SIGNAL WHICH IS AVAILABLE FOR

TRANSMISSION WHEN ALL THE MUXING IS OVER.


PATH• PATH INDICATES THE LANE THROUGH WHICH

THE INPUT SIGNAL IS ALLOWED TO PASS TO REACH UP TO HIGHER ORDER PATH OR TO SOME OTHER HIGHER LEVEL


SECTION• SECTION INDICATES THAT NOW DATA IS

PROCESSED COMPLETELY AND IS AVAILABLE FOR

MODULATION OVER THE LASER

• IN MOST OF THE CASES SOME OVERHEAD HOUSE

KEEPING BITS ARE ALSO ADDED JUST BEFORE

MODULATION


CONTAINER

• AS THE NAME SUGGESTS IT IS A BOX OF FIXED

SIZE WITH VERY LITTLE ELASTICITY

• THIS BOX CAN TAKE VARIETY OF PDH

INPUTS( MAX=2).

• CONTAINER IS THE FIRST ITEM IN THE CHAIN OF SDH

MAPPING/MULTIPLEXING


VIRTUAL CONTAINER

• IT IS THE SECOND ITEM IN THE CHAIN OF

MULTIPLEXING

• CONTAINER ADDED WITH SOME PATH OVERHEAD

IS CALLED VIRTUAL CONTAINER

• CONTAINER AND VIRTUAL CONTAINER ARE

CALLED PATH


PATH LEVEL• IF WE ARE STARTING THE MUX CHAIN FROM 2MB OR

1.5MB LEVEL THEN WE ARE FOLLOWING THE

LOWER ORDER PATH.

• IF WE ARE STARTING THE MUX CHAIN FROM 34 OR

140 MB LEVEL THEN WE ARE AT THE HIGHER

ORDER PATH.


TU

VC

C

FIRST THREE STAGES OF MULTIPLEXING

PATH


TRIBUTARY UNIT

• TRIBUTARY UNIT IS AN AGENT THAT PROVIDES

ADAPTATION OR HANDSHAKE BETWEEN HIGHER

ORDER PATH AND LOWER ORDER PATH


VIRTUALCONTAINER

CONTAINER

POINTER

TRIBUTARY UNIT


ADMINISTRATIVE UNIT

• ADMINISTRATIVE UNIT PROVIDES ADAPTATION OR

HANDSHAKE BETWEEN FINAL FRAME

LAYER(SECTION LAYER) AND HIGHER ORDER PATH

LAYER


POINTER• AS THE NAME INFERS, POINTER POINTS TO THE

START OF THE FRAME WHEN COMPARED TO

OMNIPRESENT SYCHRONOUS CLOCK

• VALUE OF THE POINTER INDICATES THE ACTUAL

OFFSET


SDH MAPPING

• SDH MAPPING IS THE PROCESS BY WHICH INPUT

DATA IS FILLED IN THE FIRST BOX ,THAT IS,

CONTAINER.

• DATA MAY NOT BE OF THE IDEAL SIZE TO GET

ADJUSTED IN THE BOX BUT VARIATIONS SHOULD

NOT EXCEED THE ELASTIC LIMIT OF THE BOX


SDH MULTIPLEXING

• PROCESS OF ADAPTAION OF LOWER ORDER PATH

IN TO HIGHER ORDER PATH IS CALLED

MULTIPLEXING.

• PROCESS OF ADAPTAION OF HIGHER ORDER PATH

IN TO SECTION LAYER IS ALSO CALLED

MULTIPLEXING.


SDH ALIGNING• ALIGNING IN SDH IS CALLED THE ALIGNING OF THE

LOCAL FRAME OF SDH WITH THE GLOBAL CLOCK

FLOWING IN THE RING.

• ALIGNING TAKES PLACE AT THE ADMINISTRATIVE

UNIT


SDH RATES• STM-1 = 155.520 MB/S

• STM-4 = 622.080 MB/S

• STM-16 = 2488.32 MB/S

• STM-64 = 9953.28 MB/S


NO OF ROWS IN FRAME: 9NO OF COLUMNS: 270NO OF BYTES IN FRAME: 270*9NO OF BITS IN A FRAME: 270*9*8FRAME DURATION: 125usNO OF BITS TRANSMITTED IN ONE SECOND: 270*9*8*1000000 -------------------------- 125

=155.520Mb/S

SDH BIT RATE CALCULATION


POINTER PAY LOAD

RSOH

OVERHEAD

MSOH

1

9

2709

34

FINAL SDH FRAME


C4C4140MB/S

C4C4+

POH

= VC4VC4

MAPPING OF PDH 140 Mbs



VC4VC4+POINTER

VC4VC4 AU-4


FLOATING PAYLOAD

VC4VC4 AU-4

VC4VC4 AUG

FIXED PAYLOAD



STM-IMSOHMSOH

VC4VC4 AUG+

RSOHRSOH

MSOHMSOH

= VC4VC4

RSOHRSOH




+

C3

C3 POH VC3

34MB/S


VC3

+ =

POINTER

TU3



TU3

AFTER ALIGNMENT =

TUG3



TUG3 TUG3TUG3

VC-4



VC4VC4+POINTER

VC4VC4 AU-4



VC4VC4 AU-4

VC4VC4 AUG

FIXED PAYLOAD



MSOHMSOH

VC4VC4 AUG+

RSOHRSOH

MSOHMSOH

= VC4VC4

RSOHRSOH



2MB

C1VC12

PATH OVER HEAD




VC12 TU12

+

POINTER


TU12 TU12 TU12

TUG 2



C12

VC12POH

TU12POINTER

TU12

TU12 TU12 TU12

TUG2



TUG2 TUG2 TUG2 TUG2

1 2 3 7

TUG3NPI

NPI



TUG3 TUG3TUG3

VC-4




VC4VC4+POINTER

VC4VC4 AU-4


VC4VC4 AU-4

VC4VC4 AUG

FIXED PAYLOAD



STM-IMSOHMSOH

VC4VC4 AUG+

RSOHRSOH

MSOHMSOH

= VC4VC4

RSOHRSOH



TUG3 TUG3TUG3



TUG2

TUG2

TUG2

TUG2

TUG2

TUG2

TUG2 TUG2TUG2

TUG2 TUG2

TUG2 TUG2

TUG2 TUG2

TUG2

TUG2 TUG2

TUG2

TUG2

TUG2



TUG2

TUG2

TUG2

TUG2

TUG2

TUG2

TUG2TUG2

TUG2 TUG2

TUG2 TUG2

TUG2 TUG2

TUG2

TUG2 TUG2

TUG2

TUG2

TUG2

TU12 TU12 TU12

TUG2

TU12 TU12 TU12 TU12 TU12 TU12


PAYLOAD


SDH-MAPPING

• MAPPING IS THE PROCESS THROUGH WHICH

PDH TRIBUTARY IS ALLOWED TO BE ADAPTED

IN THE CONTAINER

• FOR THREE DIFFERENT TRIBUTARY THERE ARE THREE DIFFERENT CONTAINERS


MAPPING OF 139.264Kb/S

• THIS SIGNAL, E4 WILL GO TO C-4, C-4 HAS 9 ROWS AND 260 COLUMNS IN 125 MICROSECONDS

• ONE ROW IS BIFURCATED IN TO 20 BLOCKS OF 13 BYTES

• ONE BLOCK IS IN THE FORM OF ONE BYTE IN THE FORM OF W/X/Y/Z BYTE FOLLOWED BY 12 BYTES OF DATA


G.709 MAPPING GRAPH

W =D1..D8, Y=R1..R8, X = CR1..R7, Z = D1..D6SR

=DATA

= W

=X

= Y

=Z


PERMISSIBLE OFFSET CALCULATION

• TOTAL NUMBER OF INFORMATION BITS IN

ONE ROW = 1934 BITS

• JUSTIFICATION BITS = 5

• OPPORTUNITYBITS = 1

• STUFF B ITS = 140


MAPPING OF E3 IN C3

• C-3 IS 9 ROWS BY 84 COLUMNS IN 125

MICROSECONDS

• THIS PAYLOAD IS DIVIDED IN TO THREE• SUBFRAMES

• EACH SUBFRAME IS DIVIDED IN THREE ROWS

• EACH ROW IS DIVIDED IN TO 16 BLOCKS OF 4

BYTES AND 4 BLOCKS OF 5 BYTES


X X X Y X X X X

Z X

X B

X

X X X A X X X

X = R+24BITS

Y = RR+24BITS

Z=RC+24BITS

A=RR + 24BITSB=RC +24BITS

FIRST ROW

R= ALL FIXED STUFFC= 6 FIXED STUFF BITS +2 CBITS


X X X Y X X X X

Z X

X B

X

X X X A X X X

X = R+24BITS

Y = RR+24BITS

Z=RC+24BITS

A=RR + 24BITSB=RC +24BITS

R= ALL FIXED STUFFC= 6 FIXED STUFF BITS +2 CBITS

SECOND ROW


X X X Y X X X X

Z X

X B1

X

X X X A X X X

X =R+24BITS

Y = RR+24BITS

Z=RC+24BITS

A=RR+ 24BITSB1=RR +a + b+8BITS

THIRD ROW

a+b = 7 R BITS + 7 D BITS + 2 S BITS



• TOTAL NUMBER OF DATA BITS IN SUBFRAME

=1431

• JUSTIFICATION BITS = 10

• OPPORTUNITY BITS = 2

• FIXED STUFF BITS = 573


MAPPING OF E1 IN TO C12

• C12 IS 136 BYTES IN 500 MICROSECOND

• IT IS ONLY IN THE CASE OF E1 THAT THE

FRAMEDURATION IS FOUR FOLD ELSE IT IS 125

MICROSECOND TO MAKE THE THINGS CLEAR

IT IS CALLED MULTIFRAME


32 BYTES 32BYTES 32BYTES 31BYTER8 R8C1C2R6

R8C1C2R6

R8

C1C2R5S1

R8S2D7

C12 CONFIGURATION

500 MICROSECONDS



• TOTAL NUMBER OF INFORMATION BITS =1023

• JUSTIFICATION BITS=6

• OPPORTUNITY BITS=2

• FIXED STUFF BITS =57

• IN 500 MICROSECONDS


A1 A1 A1 A2 A2 A2 J0B1D1

E1D2

F1D2

B2 B2 B2 K1

D5D8

D11

D4

D7D10S1

K2D6D9

D12

E2M1RSOH: ROWS 1-3MSOH: ROWS 5-9BYTES LOCATION FOR STM-N: IDENTIFIED BY S(a,b,c);

a=row; b=column; c=depth.

DESCRIPTION OF OVERHEADS BYTES

POINTER


A1 & A2 FRAMING BYTES; A1=11110110, A2=00101000

J0 &Z0 J0 at S(1,7,1) USED AS SECTION ACCESS POINTIDENTIFIER USING A 16-BYTE FRAME.Z0 at S(1,7,2) - S(1,7,N) RESERVED FOR FUTURE USE

B1 BIP-8; FOR REGN. SECTION ERROR MONITORING

E1 ORDERWIRE IN REGN. SECTION

F1 USER CHANNEL TO PROVIDE DATA/VOICE CONNECTION FOR MTCE PURPOSES.

D1-D3 DCC FOR REGN. SECTION (192 kbps)

DESSCRIPTION OF SECTION OVERHEADS BYTES


Thank you.

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Sdh Multiplexing