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08.04.23 09:03 The World of Synchronous Networks 1
• Current transmission technologies (PDH)• The Synchronous Digital Hierarchie (SDH)• Bit rates, frame structures and interfaces in SDH• Basic elements of STM-1• SDH network elements• Synchronization architecture in SDH• Monitoring, maintenance and measurements in SDH• International SDH Network standards• Future Trends
Copyright by Stephan Schultz, Wandel & Goltermann GermanyBox 1262, D-72795 Eningen u.A.e-mail: [email protected]://www.wg.com
All rights reserved.No parts of this book may be reproduced by any means, or transmitted, or translated without the written permission of the publisher.
Basics on SDH from STM-1 up to STM-16
08.04.23 09:03 The World of Synchronous Networks 2
Current Transmission Technologies
08.04.23 09:03 The World of Synchronous Networks 3
The Telephone System
LE LE
08.04.23 09:03 The World of Synchronous Networks 4
T1 T2 T3
T4 T5 T6 T7time Audio Signal
Sampler Output
timeT1 T2 T3
T4 T5 T6 T7
Pulse Amplitude Modulated (PAM)
signal
Sampling
08.04.23 09:03 The World of Synchronous Networks 5
+V0 0 0 0 X XXX
0 0 0 1 X XXX
0 0 1 0 X XXX
1 0 0 0 X XXX
1 0 0 1 X XXX
1 0 1 0 X XXX
1 0 1 1 X XXX
1 1 0 0 X XXX
1 1 0 1 X XXX
1 1 1 0 X XXX
1 1 1 1 X XXX
digital codesQuantization
Level
3248648096112
-VIn accordance with
CCITT’s A-law
1/2V1/4V
1/8V
1/16V
1/32V
1/64V
Non-Linear Quantization and Encoding
08.04.23 09:03 The World of Synchronous Networks 6
8bits per sample
x = 64kbit/s8000
samples per sec
PCM Signal Data Rate
08.04.23 09:03 The World of Synchronous Networks 7
Time Division Multiplexing (TDM)
08.04.23 09:03 The World of Synchronous Networks 8
2048 kbit/s2048 kbit/s
64 kbit/s64 kbit/s
x 4
x 30/31x 24
x 3
x 7x 5
x 3
Japan USA Europe
primary rate
2. order
3.
4.
5.
32064 kbit/s32064 kbit/s
x 3
97728 kbit/s97728 kbit/s
397200 kbit/s397200 kbit/s
x 4
x 4
34368 kbit/s34368 kbit/s
139264 kbit/s139264 kbit/s
x 4
564992 kbit/s564992 kbit/s
x 4
8448 kbit/s8448 kbit/s
44736 kbit/s44736 kbit/s
274176 kbit/s274176 kbit/s
x 6
1544 kbit/s1544 kbit/s
6312 kbit/s6312 kbit/s
x 4
PDH Systems Worldwide
08.04.23 09:03 The World of Synchronous Networks 9
64 kbit/s Data Signals
15 kHzSound ProgramSignals
139264 kbit/s (+/-15ppm)
1
2048 kbit/s (+/-50ppm)
8448 kbit/s (+/-30ppm)
34 368 kbit/s (+/-20ppm)
64 Channel Capacity:64 x 30 = 1920
0.3 to 3.1 kHzAF signals
DSMX34/140
DSMX8/34
DSMX2/8
1
30
DSMX64k/2
1
30
PCMX 30
1
PCMX 30
5
1
30
4
1
4
PDH Multiplex / Demultiplex
08.04.23 09:03 The World of Synchronous Networks 10
2.448 kbit/s frame: 32x8 bit=256 bit in 125µs
encoded voice / data signals encoded voice / data signals
signallinginformation
timeslots0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
2 Mbit/s Frame Structures
08.04.23 09:03 The World of Synchronous Networks 11
Si: Reserved for international useSa4: Non urgent Alarm (0=Alarm)A: Remote alarm (1=urgent Alarm)
Sa4 to Sa8: Spare bits or used for message based data links (point-to-point applications)FAS: Frame alignment signal (0011011)NFAS: Non frame alignment signal
2.448 kbit/s frame: 32x8 bit=256 bit in 125µs
Si 0 0 1 1 0 1 1
encoded voice / data signals encoded voice / data signals
signallinginformation
timeslots
Si 1 A Sa Sa Sa Sa Sa 4 5 6 7 8
FAS(frames 0,2,4...)
NFAS(frames 1,3,5...) (M)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
2 Mbit/s Frame Structures
08.04.23 09:03 The World of Synchronous Networks 12
Si: Reserved for international useSa4: Non urgent Alarm (0=Alarm)A: Remote alarm (1=urgent Alarm)Y: Remote MF alarm (1=Alarm)E: CRC error indication (0=Error)
Sa4 to Sa8: Spare bits or used for message based data links (point-to-point applications)FAS: Frame alignment signal (0011011)NFAS: Not frame alignment signal
signallingsubscr. n
signallingsubscr. n+15
2.448 kbit/s frame: 32x8 bit=256 bit in 125µs
Si 0 0 1 1 0 1 1
encoded voice / data signals encoded voice / data signals
signallinginformation
timeslots
Si 1 A Sa Sa Sa Sa Sa 4 5 6 7 8
FAS(frames 0,2,4...)
NFAS(frames 1,3,5...) (M)
0 0 0 0 x Y x x
a b c d a b c d
MFAS NMFASframe 0
frames 1... 15 & 17...31
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
2 Mbit/s Frame Structures
08.04.23 09:03 The World of Synchronous Networks 13
2.448 kbit/s Multiframe, ITU-T G.704
fr 15 fr 0 fr 1 fr 2 fr 3 fr 4 fr 5 fr 6 fr 7 fr 8 fr 9 fr 10 fr 11 fr 12 fr 13 fr 14 fr 15
multiframe
sub multiframe 1 sub multiframe 2
Si: Reserved for international useSa4: Non urgent Alarm (0=Alarm)A: Remote alarm (1=urgent Alarm)Y: Remote MF alarm (1=Alarm)
Sa4 to Sa8: Spare bits or used for message based data links (point-to-point applications)FAS: Frame alignment signal (0011011)NFAS: Not frame alignment signal
signallingsubscr. n
signallingsubscr. n+15
2.448 kbit/s frame: 32x8 bit=256 bit in 125µs
Si 0 0 1 1 0 1 1
encoded voice / data signals encoded voice / data signals
signallinginformation
timeslots
Si 1 A Sa Sa Sa Sa Sa 4 5 6 7 8
FAS(frames 0,2,4...)
NFAS(frames 1,3,5...) (M)
0 0 0 0 x Y x x
a b c d a b c d
MFAS NMFASframe 0
frames 1... 15 & 17...31
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
2 Mbit/s Frame Structures
08.04.23 09:03 The World of Synchronous Networks 14
2.448 kbit/s Multiframe, ITU-T G.704
fr 15 fr 0 fr 1 fr 2 fr 3 fr 4 fr 5 fr 6 fr 7 fr 8 fr 9 fr 10 fr 11 fr 12 fr 13 fr 14 fr 15
multiframe
sub multiframe 1 sub multiframe 2
Si: Reserved for international useSa4: Non urgent Alarm (0=Alarm)A: Remote alarm (1=urgent Alarm)Y: Remote MF alarm (1=Alarm)E: CRC error indication (0=Error)M: Transmitting CRC multiframe alignment signal ( CRC MFAS: 001011 )Sa4 to Sa8: Spare bits or used for message based data links (point-to-point applications)FAS: Frame alignment signal (0011011)NFAS: Not frame alignment signal
signallingsubscr. n
signallingsubscr. n+15
Si 0 0 1 1 0 1 1
Si 1 A Sa Sa Sa Sa Sa 4 5 6 7 8
FAS(frames 0,2,4...)
NFAS(frames 1,3,5...) (M)
0 0 0 0 x Y x x
a b c d a b c d
MFAS NMFASframe 0
frames 1... 15 & 17...31
Time slot 0 of CRC multiframe:
sub
mul
tifra
me
1su
b m
ultif
ram
e 2
2.448 kbit/s frame: 32x8 bit=256 bit in 125µs
encoded voice / data signals encoded voice / data signals
signallinginformation
timeslots0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
0 FAS C1 0 0 1 1 0 1 1
C4 0 0 1 1 0 1 1
C1 0 0 1 1 0 1 1
C4 0 0 1 1 0 1 1
0 1 A Sa Sa Sa Sa Sa
1 1 A Sa Sa Sa Sa Sa
1 1 A Sa Sa Sa Sa Sa
E2 1 A Sa Sa Sa Sa Sa
1 NFAS
6 FAS
7 NFAS
8 FAS
9 NFAS
14 FAS
15 NFAS
256 X 8 bit = 2048 bit
256 X 8 bit = 2048 bit
2 Mbit/s Frame Structures2 Mbit/s Frame Structures
08.04.23 09:03 The World of Synchronous Networks 15
1c 2c 3c 4c s1 s2 s3 s4
1 1 1 1 0 1 0 0 0 0 A N
1a 2a 3a 4a 1b 2b 3b 4b
8.448 kbit/s; frame length 848 bit; 100.4 us; ITU-T G.742
A: Alarm BitN: National Spare Bit1a: Stuffing Control BitS: Stuffing Bit
10 200 208 208 2042 4 4 4 4
Plesiochronous Hierarchies - Frame Structures
08.04.23 09:03 The World of Synchronous Networks 16
1c 2c 3c 4c s1 s2 s3 s4
1 1 1 1 0 1 0 0 0 0 A N
1a 2a 3a 4a 1b 2b 3b 4b
8.448 kbit/s; frame length 848 bit; 100.4 us; ITU-T G.742
34.368 kbit/s; frame length 1536 bit; 44.7 us; ITU-T G.751
1 1 1 1 0 1 0 0 0 0 A N
A: Alarm BitN: National Spare Bit1a: Stuffing Control BitS: Stuffing Bit
10 200 208 208 2042 4 4 4 4
10 372 380 380 3762 4 4 4 4
1c 2c 3c 4c s1 s2 s3 s4 1a 2a 3a 4a 1b 2b 3b 4b
Plesiochronous Hierarchies - Frame Structures
08.04.23 09:03 The World of Synchronous Networks 17
139.264 kbit/s; frame length 2928 bit; 21 us; ITU-T G.751
A: Alarm BitN: National Spare Bit1a,b,c,d: Stuffing Control BitS: Stuffing Bit
1a 2a 3a 4a 1c 2c 3c 4c 1d 2d 3d 4d1b 2b 3b 4b 1e 2e 3e 4e s1 s2 s3 s4
1 1 1 1 1 0 1 0 0 0 0 0 A N N N
12 472 484 484 4844 4 4 4 4844 48044
Plesiochronous Hierarchies - Frame Structures
08.04.23 09:03 The World of Synchronous Networks 18
AISPDHEquipment
AISPDHEquipment
LOSLOFAIS
D-Bit
BER 10-3
D-Bit
BER 10-6
N-Bit
PDH Maintenance Signals
08.04.23 09:03 The World of Synchronous Networks 19
OLTU
34 - 140
8 - 34
2 - 8
OLTU
34 - 140
8 - 34
2 - 8
OLTU
34 - 140
8 - 34
2 - 8
OLTU
34 - 140
8 - 34
2 - 8
main
stand-by
140 Mbit/s 140 Mbit/s
Line Terminating Unit
Line Terminating Unit
Drop & Insert Station
1,2 ................. 64 1,2 ................. 64
Plesiochronous Drop & Insert
08.04.23 09:03 The World of Synchronous Networks 20
The Synchronous Digital Hierarchy (SDH)
08.04.23 09:03 The World of Synchronous Networks 21
Simpler multiplexing(low SDH level can be directly identified from higher SDH level)
Simple D&I of traffic channels(direct access to lower level systems without synchronization)
Allows mixing of ANSI and ETSI PDH systems
SDH is open for new applications (It can carry PDH, ATM, HDTV, MAN,...)
SDH provides TMN (ECCs)(for centralized network control)
Why SDH
08.04.23 09:03 The World of Synchronous Networks 22
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
Synchronous Network Structure
08.04.23 09:03 The World of Synchronous Networks 24
VC-2VC-1
VC-2VC-1
VC-4VC-3VC-12
VC-4VC-3
VC-2VC-1
VC-4 VC-3 VC-12
VC-4VC-3
Reg
S M
X
S M
X
MultiplexSection
Regenerator Sections
Higher Order Path
Lower Order Path
STM-nRSOH
STM-nRSOH
STM-n MSOH
VC-4/3 POH
VC-1/2/3 POH
Path Denominations
08.04.23 09:03 The World of Synchronous Networks 25
MU
X /
DE
MU
X
MU
X /
DE
MU
XPDH PDHSDH SDH SDH
Reg.
CC
NNI NNI NNI
ITU-T Rec.:G.707 BitratesG.708 Signal Structure (NNI)G.709 Synchronous Multiplex StructureG.703 Electrical characteristicG.957 Optical interface characteristic
The Network Node Interface (NNI) specifications are necessary to enable interconnection of synchronous digital network elements for transport of payloads
Network Node Interface (NNI)
08.04.23 09:03 The World of Synchronous Networks 26
Bit Rates, Frame Structure and Interfaces in SDH
08.04.23 09:03 The World of Synchronous Networks 28
RSOH: Regenerator section overheadMSOH: Multiplex section overheadPayload: Area for information transport
Transport capacity of one Byte: 64 kbit/sFrame capacity: 270 x 9 x 8 x 8000 = 155.520 Mbit/sFrame repetition time: 125 µs
1
3
5
9
4
270
270 Columns (Bytes)
1 9transmitrow by row
RSOH
MSOH
AU Pointer Payload(transport capacity)
STM-1 Frame Structure
08.04.23 09:03 The World of Synchronous Networks 29
C-4C-4
STM-1 Frame Structure
08.04.23 09:03 The World of Synchronous Networks 30
VC-4VC-4
C-4C-4
VC
-4 P
OH
VC
-4 P
OH
STM-1 Frame Structure
08.04.23 09:03 The World of Synchronous Networks 31
AU PointerAU Pointer
AU-4AU-4
VC-4VC-4
C-4C-4
VC
-4 P
OH
VC
-4 P
OH
STM-1 Frame Structure
08.04.23 09:03 The World of Synchronous Networks 32
1
3
5
9
4
270
270 Columns (Bytes)
1 9
RSOHRSOH AU-4AU-4
MSOHMSOH
AU PointerAU PointerVC-4VC-4
VC
-4 P
OH
VC
-4 P
OH
C-4C-4
STM-1 Frame Structure
08.04.23 09:03 The World of Synchronous Networks 33
12341234123412 . . . .
11111
22222
33333
44444
STM-1 #1
STM-1 #2
STM-1 #3
STM-1 #4
STM-4
The STM-4/16 bit rate is obtained by byte-interleaved multiplexing of the STM-1 tributary signals.
Clock offset at the tributary side is taken into consideration by pointer adaptation on the STM-n output signal.
B1B2
B1B2
termination new
Higher SDH Bitrates
08.04.23 09:03 The World of Synchronous Networks 34
STM-4 SOH
A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A2 A2 A2 A2 A2 A2 A2 A2 A2 A2 A2 A2 J0 Z0 Z0 Z0 X X X X X X X X
B1 E1 F1 X X X X X X X X X X X X
D1 D2 D3 X
D4
B2 B2 B2 B2 B2 B2 B2 B2 B2 B2 B2 B2 K1 K2
D7
D10
S1Z1 Z1 Z1 Z1 Z1 Z1 Z1 Z1 Z1 Z1 Z1 Z2 Z2 M1 Z2 Z2 Z2 Z2 Z2 Z2 Z2 Z2 E2 E2 X X X X X X X X X X X
D5
D8
D11
D12
D9
D5
36 bytes
B1 and B2 bytes are being recalculatedBytes E1, F1, K1, K2, D1 to D3 and D4 to D12 are taken from tributary #1
A U Pointers
Payload
#1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4 #1 #2 #3 #4
STM-4 Frame Structure
08.04.23 09:03 The World of Synchronous Networks 35
Basic Elements of STM-1
08.04.23 09:03 The World of Synchronous Networks 36
MU
X /
DE
MU
X
MU
X /
DE
MU
X
back-up line
PDH PDHSDH SDH SDH
Multiplex Section Multiplex Section
Regenerator Section Regenerator Section
Reg.
CC
clock
clock
clock
B1 B1
B3
B2B2
P a t h
Parity Bytes
F2 E1, F1, D1 ... D3E2, D4 ... D12
Comm.Channels
Synchronous Network
08.04.23 09:03 The World of Synchronous Networks 37
J1B3C2G1F2H4F3K3N1
V5J2N2K4
AU - PTR
VC-3/4 POH
VC-11/12/ 2 POH
STM-1 SOH
Media dependent bytesX Reserved for national use
SOH: Section overheadPOH: Path overhead
The overheads (SOH, POH) are used for maintenance and supervision of the SDH transmission network.
RSOH
MSOH Payload
P
O
H
Pointer
A1 A1 A1 A2 A2 A2 J0 X X
D1 D2 D3
B2 B2 B2 K1 K2D4 D5 D6 D7 D8 D9
D10 D11 D12 S1 Z1 Z1 Z2 Z2 M 1 E2 X X
B1 E1 F1 X X
H1 Y Y H2 1 1 H3 H3 H3
Embedded Overhead Bytes
08.04.23 09:03 The World of Synchronous Networks 38
Parity check(B1 calculated by regenerator and multiplexers)
Data communication channels(D1...D3, F1 between regenerators)
Voice communication channels(E1 between regenerators)
Frame Alignment(A1, A2)
Section Trace(J0 Identfication of regenerator source)
A1 A1 A1 A2 A2 A2 J0
B1 E1 F1
D1 D2 D3
B2 B2 B2 K1 K2
D4 D5 D6
D7 D8 D9
D10 D11 D12
S1 M1 E2
AU - Pointer
Functions of Regenerator Section Overhead
08.04.23 09:03 The World of Synchronous Networks 39
Parity check (B2)
Alarm information (K2)
Remote error indication (M1,K2)
Automatic protection switching(K1, K2 Bytes)
Data communication channels(D4 to D12 between multiplexers)
Clock source information (S1)
Voice communications channels(E2 between multiplexers)
A1 A1 A1 A2 A2 A2 J0
B1 E1 F1
D1 D2 D3
B2 B2 B2 K1 K2
D4 D5 D6
D7 D8 D9
D10 D11 D12
S1 M1 E2
AU - Pointer
Functions of Multiplexer Section Overhead
08.04.23 09:03 The World of Synchronous Networks 40
Parity check B3, V5/ BIP-2 calculated by path terminating point
Alarm and performance information (V5, G1)
Structure of the VC Signal label C2
Multiframe indication for TUs (H4)
User communications channelbetween path elements (F2, F3)
Identification of the Path Source (Path Trace J1, J2)
J1B3C2G1F2H4F3K4N1
V5J2N2K4
VC-3/4 POH
VC-11/12/2 POH
Functions of Path Overhead
08.04.23 09:03 The World of Synchronous Networks 41
The Container (C) Basic packaging unit for tributary signals (PDH) Synchronous to the STM-1 Bitrate adaptation is done via a positive stuffing procedure Adaptation of synchronous tributaries by fixed stuffing bits Bit by bit stuffing
The Virtual Container (VC) Formation of the Container by adding of a POH (Path Overhead) Transport as a unit through the network (SDH) A VC containing several VCs has also a pointer area
Functions and Characteristics of the Individual Elements of the NNI
08.04.23 09:03 The World of Synchronous Networks 42
The Tributary Unit (TU) Is formed via adding a pointer to the VC
The Tributary Unit Group (TUG) Combines several TUs for a new VC
The Administrative Unit (AU) Is shaped if a pointer is allocated to the VC formed at last
The Syncronous Transport Module Level 1 (STM-1) Formed by adding a Section Overhead (SOH) to AUs Clock justification through positive-zero-negative stuffing in the AU
pointer area byte by byte stuffing
Functions and Characteristics of the Individual Elements of the NNI
08.04.23 09:03 The World of Synchronous Networks 43
A1, A2 Frame synchronisationB1, B2 Parity bytes for transmission error monitoringJ0 Regenerator section trace D1... D3 Regenerator section DCCD4.. D12 Multiplex section DCCE1, E2 Orderwire for voice communicationF1 User channel for maintenance purposes (data, voice)K1, K2 Automatic protection switching (APS)S1 Synchronisation status messageM1 MS-REI (remote error idication)
J1 Higher order path traceB3 Path parity byte for error monitoringC2 Signal Label (composition of payload)G1 Path status and performanceF2, F3 Path user channelsH4 Payload specific byteK3 Automatic protection switching (APS)N1 Network operator byte (Tandem Connection Monit.)
V5 Error check, path status, signal labelJ2 Lower order path traceN2 Network operator byte (Tandem Connection Monit.)K4 Automatic protection switching (APS)
SOH
VC-3/4POH
VC-1/2POH
Overhead Byte Functionality
08.04.23 09:03 The World of Synchronous Networks 44
ContainerContainer
Virtual ContainerVirtual Container
Administrative UnitAdministrative Unit
Synchronous Transport ModuleSynchronous Transport Module
Path Overhead
Pointer
Section Overhead
Plesiochronous signal 140Mbit/s
C4
VC-4
AU-4
STM-1
The way of integrating PDH signals into STM-1
08.04.23 09:03 The World of Synchronous Networks 45
The pointer technology provides a means to accommodate timing differences at SDH networks.The pointer indicates the start of the payload within a STM-1frame.
AU-Pointer
1
9
TU-PTR
VC
-4 P
OH
VC-12POH
VC-12
VC-4
STM-1
Pointers
08.04.23 09:03 The World of Synchronous Networks 46
H1 Y Y H2 1 1 H3 H3 H3
Opportunity fornegative stuffing(more capacity)
Pointerinc/decIDIDIDID
NDF,mapping struc,pointer inc/dec
J1
C4 payload
N N N N S S I D I D I D I D I D
H1 byte H2 byte
0 1 1 0 1 0 0 1 1 0 0 1 X X X X X X X X X X X X X X X X X X X X 1 0 0 1 S S 1 1 1 1 1 0 0 0 0 0
Opportunity forpositive stuffing(less capacity)
Pointer interpretation :
New data flag (NDF) disabled :New data flag enabled :AU/TU type AU-4/TU-3 :AU/TU type AU-3/TU-3 :AU-4 pointer 0...782 :TU-3 pointer 0...764 :Null pointer indication (NPI) :
Use of the AU-4 Pointer Area, Coding
08.04.23 09:03 The World of Synchronous Networks 47
Frequency justification of several STM-1 signals running into a network node (Pointer Stuffing)
RSOH
MSOH
H1 H2 H3
RSOH
MSOH
H1 H2 H3
1 9 270
RSOH
MSOH
H1 H2
RSOH
MSOH
H1 H2 H3
125µs
250µs
375µs
500µs
Start of VC-4
negative justification byte (data)
Pointer with inverted D bits
New pointer
Actual pointer
Not Synchronous SDH Networks
08.04.23 09:03 The World of Synchronous Networks 48
AU Pointer
RSOH
MSOH
9 261
J1B3C2G1F2H4Z3K3Z5
20 x 13 bytes per row
C-4140 Mbit/s
260
C-4 transport capacity: 260 x 9 x 64 kbit/s = 149.760 kbit/s
Container C-4 contains a 140 Mbit/s PDH Tributary
Mapping 140 Mbit/s
08.04.23 09:03 The World of Synchronous Networks 49
W = I I I I I I I I Y = RRRRRRRR X = CRRRROOO Z = I I I I I I SR
I = Information bitS = Justification opportunity bit
R = Fixed stuffing bitC = Justification control bit
O = Overhead bit
The figure shows one row of the VC-4
96 IW 96 IY96 IY96 IY96 IX
96 IX 96 IX96 IY96 IY96 IY
96 IY 96 IY96 IX96 IY96 IY
96 IY 96 IZ96 IY96 IX96 IY
J1
Mapping of a 140 Mbit/s Tributary into VC-4
08.04.23 09:03 The World of Synchronous Networks 50
AU Pointer
RSOH
MSOH
J1B3C2G1F2H4Z3K3Z5
H1 H1 H1 H2 H2 H2
H3 H3 H3
260
fixed stuffing
Container C-4 contains 3 times a 34 Mbit/s PDH Tributary (ETSI structure)
C-3 transport capacity: 84 X 9 x 64 kbit/s = 48.384 kBit/s84
C-3
J1B3C2G1F2H4Z3K3Z5
J1B3C2G1F2H4Z3K3Z5
J1B3C2G1F2H4Z3K3Z5
C334 Mbit/s
9 261
VC-3 #1VC-3 #2
VC-3 #3
VC-4 POH
VC-3 POH
Mapping 34 Mbit/s
08.04.23 09:03 The World of Synchronous Networks 51
RSOH
MSOH
AU pointer
VC-4
TUG-3
TUG-2
TU
-12
VC-12
Tu pointer
Mapping 2 Mbit/s
08.04.23 09:03 The World of Synchronous Networks 52
AU-4 Pointer
RSOH
MSOH
J1
B3
C2
G1
F2
H4
Z3
K3
Z5
1 2 3 4 5 6 7 8 9 10...........................................261
A B C A B C A A B C
S
T
U
F
F
I N
G
S
T
U
F
F
I N
G
. ......
1 86TUG-3(A)
. ......
1 86TUG-3(C)
. ......
1 86TUG-3(B)
Mapping and Multiplexing (1)
08.04.23 09:03 The World of Synchronous Networks 53
1 2 3 4 5 6 7 8 9 10...........................................86
NPI
E3 F3 G3S T
U
F
F I
N
G
S
T
U
F
F
I N
G
A1 B1 C1 D1 E1 F1 G1 A2
1 2 3 1 2 3 1 2 3 1 2 3
TU-12#1
TUG-2(A)
TU-12#3
.....
1 2 3 1 2 3 1 2 3 1 2 3
TU-12#1
TUG-2(B)
TU-12#3
.....
1 2 3 1 2 3 1 2 3 1 2 3
TU-12#1
TUG-2(G)
TU-12#3
.....
TUG-3NPI: Null Pointer Indication1001 XX11 1110 0000 XXXX XXXX
TU-12s occupy 36 bytes per frame
Mapping and Multiplexing (2)
08.04.23 09:03 The World of Synchronous Networks 54
V5R
32 bytes (32x8I)
RJ2
C1 C2 O O O O R R
32 bytes (32x8I)
32 bytes (32x8I)
32 bytes (32x8I)
RK4
R
N2R
C1 C2 O O O O R R
S2 I I I I I I I
14
0 B
yte
s
35 bytes in one VC-4
500 µs
V5: VC-12 Path OverheadR: fixed stuffing bitsJ2: Path TraceC1/2: Justification control bitO: Overhead bitN2: Network Operator byteK4: APSS2: Justification opportunity bitI: Info-bit
PayloadVC-4 Payload
V4
XXX XX00
PayloadVC-4 Payload
V1
XXX XX01
PayloadVC-4 Payload
V2
XXX XX10
PayloadVC-4 Payload
V3
XXX XX11
PayloadVC-4 Payload
V4
XXX XX00
VC-12 Structure:
H4: Indicates the number of VxV1,V2,V3: TU-12 Pointer
H4
H4
H4
H4
H4
VC-4 POH
Mapping 2 Mbit/s (asynchronous)
08.04.23 09:03 The World of Synchronous Networks 55
AU-4 Pointers
MSOH
RSOH
STM-4
VC-4-4c
J1
C2
G1
F2
H4
F3
K3
N1
C-4-4cF
ixe
d S
tuff
Fix
ed
Stu
ff
Fix
ed
Stu
ff
4 x 9 bytes 4 x 261 bytes
4 x 261 bytes
ATM CellThe first Pointer indicates J1All other Pointers are set to "Concatenation Indication"
B3
VC-4 Contiguous Concatenation
08.04.23 09:03 The World of Synchronous Networks 56
ATM switchSDH cross-connect for VC-4
ATM switch
150 Mbit/s
600 Mbit/s
In
Out
Out
In
Out
In
In
Out
VC-4-4c
STM-4c portSTM-4c port
STM-4 portSTM-4 port
150 Mbit/s
150 Mbit/s
150 Mbit/s
?VC4VC4
VC4VC4
4 x
Differentdelays for VC-4's?
622 Mbit/s622 Mbit/s
How to transport 600 Mbit/s ATM via 150 Mbit/s SDH?
08.04.23 09:03 The World of Synchronous Networks 57
Generation:All Pointers are set to the same valueAll VC-4 should be kept in the same STM-4All VC-4 are transported as individual VC-4's
AU-4 Pointers
MSOH
RSOH
STM-4
VC-4-4vc
J1
B3
C2
G1
F2
H4
F3
K3
N1
C-4-4vc
4 x 9 bytes 4 x 261 bytes
4 x 261 bytes
ATM Cell
J1
B3
C2
G1
F2
F3
K3
N1
H4
J1
B3
C2
G1
F2
H4
F3
K3
N1
J1
B3
C2
G1
F2
H4
F3
K3
N1
VC-4 Virtual Concatenation (Generation)
08.04.23 09:03 The World of Synchronous Networks 58
Termination:VC-4-4vc is reconstructed using the (different) pointer values for alignment
VC-4-4vc
J1B3C2G1F2H4F3K3N1
4 x 261 bytes
ATM Cell
J1B3C2G1F2H4F3K3N1
J1B3C2G1F2H4F3K3N1
J1B3C2G1F2H4F3K3N1
J1B3C2G1F2H4F3K3N1
C-4-4vc
J1B3C2G1F2
F3K3N1
H4
J1B3C2G1F2H4F3K3N1
J1B3C2G1F2H4F3K3N1
VC-4 #1VC-4 #2 VC-4 #3
VC-4 #4
VC-4 Virtual Concatenation (Termination)
08.04.23 09:03 The World of Synchronous Networks 59
E4: 139.264 kbit/s
DS3: 44.736 kbit/sE3 : 34.368 kbit/s
AUG C-4
TUG-3 TU-3 VC-3
C-3AU-3
x1
x3
x7
x7
x3
x1
STM-N
STS-3N
AU-4STS-3C
VC-4STS-3C SPE
STS-1
VC-3STS-1SPE
TUG-2 VTgroup
x3
xN
x1
x4
DS1: 1.544 kbit/sTU-11 VC-11
C-11VT-1.5 VT-SPE
E1: 2.048 kbit/sTU-12 VC-12
C-12 VT-2 VT-SPE
SDH
SONET
ITU-T G.707
BELLCORE GR.253ANSI T1.105
ATM: 149.760 kbit/s
ATM: 48,384 kbit/s
DS2: 6.312 kbit/sTU-2 VC-2
C-2 VT-6 VT-SPE
x1
STM-0
STS-1
SDH and SONET are International Standards
08.04.23 09:03 The World of Synchronous Networks 62
SDH Network Elements
08.04.23 09:03 The World of Synchronous Networks 63
SDH Network Elements
SDH Repeater
STM-n STM-n Applications:Line Signal Regenerationin Point-to-Point and Ring Networks
Terminal Multiplexer
STM-nPDH & STM-mTributariesm<n
Applications:Point-to-PointTransmission Systems(STM-1, STM-4, STM-16)
08.04.23 09:03 The World of Synchronous Networks 64
STM-1/4STM-1/4
Tributary Ports : n x 2 Mbit/s ( 34 Mbit/s)
ADM
......
WEST EAST
Add Drop Multiplexer
08.04.23 09:03 The World of Synchronous Networks 65
16x16x
4x 4x
VC11
34
2
SDH Multiplexer
VC 4 VC 3VC 12
2.4 Gbit/s
622 Mbit/s
2.4 Gbit/s
622 Mbit/s
140 Mbit/s
34 (45)Mbit/s
2 (1.5)Mbit/s
140 Mbit/s
34 (45)Mbit/s
2 (1.5)Mbit/s
155 Mbit/s155 Mbit/s
VC12
VC3
140
VC4
VC12
VC3
140
2
2
VC12
VC12
2
2
140
VC12
2
2
34
34
2
2
VC12
140 Mbit/s
34 Mbit/s 34 Mbit/s
140 Mbit/s
VC4
140
155VC4
155 Mbit/s
Synchronous Cross Connect
08.04.23 09:03 The World of Synchronous Networks 66
Optical Receive UnitSync
DEMUX4
4
4
4
OpticalTransmit UnitSync
MUX4
4
4
4
Management Communication Unit
Service Channel Unit
OverheadProcessing Unit
Data Channels
Service Channels
PC / TMN (Q)
16 x 140 Mbit/s
or
16 x STM-1
16 x 140 Mbit/s
or
16 x STM-1
STM-16
STM-16
SLX 1/16
Synchronous Line Equipment
08.04.23 09:03 The World of Synchronous Networks 67
2Mbit/s 34Mbit/s 140Mbit/s STM-1 STM-4
SDH
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/s
34Mbit/s
140Mbit/s
STM-1 / STS-3c Gateway to SONET
ADM : Add Drop MultiplexerDXC : Digital Cross ConnectTM : Terminal Multiplexer
Hybrid Networks Connect Old and New Technologies
08.04.23 09:03 The World of Synchronous Networks 68
Local Network
STM-4
STM-16
STM-1
STM-1Exchange
FlexMux
SubscriberAccess
Mux64/2M
LocalExchange
Trunk NetworkL 1
Trunk NetworkL 2
SDH Network Topology
SDH Network Topology
Trunk Network L 2
08.04.23 09:03 The World of Synchronous Networks 69
Synchronization Architecture in SDH
08.04.23 09:03 The World of Synchronous Networks 70
Synchronization Network
PRC
SSU SSU
Primary Reference Clock
Synchronization Supply Unit
SDH Equipment ClockSEC SDH Equip.
SEC SDH Equip.
SEC SDH Equip.
Caesium (Stratum 1) requ : 1 x 10-11
typ : 5 x 10 -12
long term: holdover 24h:
Rubidium (Stratum 2) requ : 1.6 x 10-8 , 1 x 10-10
typ : 4 x 10 -11 , 2 x 10-11
08.04.23 09:03 The World of Synchronous Networks 71
Limits:
Max. 10 x G.812 TNCMax. 60 x G.813 SEC, though no more than 20 between 2 TNCs
G.811 PRC
G.812 TNC
G.812 TNC
G.813 SEC
G.813 SEC
G.813 SEC
SSU SSU
Synchronization reference model
08.04.23 09:03 The World of Synchronous Networks 72
Synchronization of SDH Network Elements
SynchronousSDH Signal
155 Mbit/sData Signal
2 Mbit/sData Signal
2 048 kHz Central Clock
SDH Network Element
Osc.
InternalOscillator± 4.6 ppm
08.04.23 09:03 The World of Synchronous Networks 73
Phase error [ ns]
Observation interval [s]0.01 1 100 10000
10
100
1000
10000
100000
Hold-over mode
08.04.23 09:03 The World of Synchronous Networks 74
Hold-over measured values (TIE)
08.04.23 09:03 The World of Synchronous Networks 75
ITU-T ANSI / Bellcore ETSI
Definitions G.810 T1.101 / GR-253 ETS 300 462-1Network G.825 T1.105 / GR-253 ETS 300 462-3Primary Reference Clocks G.811 T1.101 ETS 300 462-6Synchron. Supply Clocks (ST2) G.812 T1.101 ETS 300 462-4Equipment Clocks (ST3) G.813 (G.81s) GR-253 ETS 300 462-5
Which Recommendations define Synchronization Networks
08.04.23 09:03 The World of Synchronous Networks 76
Monitoring, Maintenance and Control Functions in SDH
08.04.23 09:03 The World of Synchronous Networks 77
LOS Loss Of Signal LOS Loss Of Signal TSE Test Sequence Error (Bit Err.) TSE Test Sequence Error LSS Loss of Sequence Synchron. LSS Loss of Sequence Synchr.LTI Loss of incoming Timing Ref. LTI Loss of inc. TimingRef OOF Out Of Frame OOF Out Of FrameLOF Loss Of Frame LOF Loss Of FrameB1 Regenerator Section BIP Err. B1 Section BIP ErrorsB2 Multiplex Section BIP Err. B2 Line BIP ErrorsMS-AIS Multiplex Section AIS AIS-L Line AISMS-RDI Mux Sect. Remote Defect Ind. RDI-L Line remote Defect Ind.MS-REI Mux Sect. Remote Errro Ind. REI-L Line Remote Error Ind.AU-LOP Loss Of AU Pointer LOP-P SP Loss Of PointerAU-NDF New Data Flag AU Pointer NDF-P SP New Data FlagAU-AIS AU Alarm Ind. Signal AIS-P SP AISAU-PJE AU Pointer Just. EventB3 HO Path BIP Errors B3 SP BIP ErrorsHP-UNEQ HO Path Unequipped UNEQ-P SP UnequippedHP-RDI HO Path Remote Defect Ind. RDI-P SP Remote Deect. Ind.HP-REI HO Path Remote Error Ind. REI-P SP Remote ERrro Ind.
PDI-P SP Payload Defect Ind.HP-TIM HO Path Trace Ident. Mismatch TIM-P SP Trace Ident. MismatchHP-PLM HO Path Payload Label Mism. PLM-P SP Payload Label MismatchTU-LOP Loss Of TU Pointer LOP-V VP Loss Of PointerTU-NDF New Data Flag TU Pointer NDF-V VP New Data FlagTU-AIS TU AIS AIS-V VP AISTU-LOM Loss Of Multiframe LOM Loss Of MultiframeBIP-2/B3 LO Path BIP Errors BIP-2 VP BIP ErrorsLP-UNEQ LO Path Unequipped UNEQ-V VP UnequippedLP-RDI LO Path Remote Defect Ind. RDI-V VP Remote Defect Ind.LP-REI LO Path Remote Error Ind. REI-V VP Remote Error Ind.LP-RFI LO Path Remote Failure Ind. RFI-V VP Remote Failure Ind.
PDI-V VP Payload Defect Ind.LP-TIM LO Path Trace Ident. Mismatch TIM-V VP Trace Ident. MismatchLP-PLM LO Path Payload Label Mism. PLM-V VP Payload Label Mism.
Mu
x S
ect.
Mu
x S
ect.P
hys
./Reg
.Sec
t.P
hys
./Reg
.Sec
t.H
igh
er O
rder
Pat
hH
igh
er O
rder
Pat
hL
ow
er O
rder
Pat
hL
ow
er O
rder
Pat
h
Lin
e (L
)L
ine
(L)
ST
S P
ath
(S
P)
ST
S P
ath
(S
P)
VT
Pat
h (
VP
)V
T P
ath
(V
P)
Ph
ys./S
ecti
on
Ph
ys./S
ecti
on
LCD Loss of Cell Delineation I.610HCOR Correctable Header ErrorsHUNC Uncorrectable Header ErrorsVP-AIS Virtual Path AIS I.610VP-RDI Virtual Path Remote Defect Indication I.610VC-AIS Virtual Channel AIS I.610VC-RDI Virtual Channel Remot Defect Indication I.610Vx-AIS Virtual Channel AIS & Virtual, Path AIS simultan. (O.191)Vx-RDI Virtual Channel RDI & Virtual, Path RDI simultan. (O.191)LOC Loss Of Continuity I.610
AT
M P
ath
AT
M P
ath
EVENTS SDHEVENTS SDH EVENTS SONETEVENTS SONET
08.04.23 09:03 The World of Synchronous Networks 78
Frame Areas Covered by Parity Bytes
RSOH
MSOH
Payload
B1:- Supervision of the whole STM-1 frame- Covers the regenerator sections of a trans- mission system
B2:- Covers the multiplex sections (from network node to network node)
B3:- Covers the transmission paths from beginning to the end (tributary to tributary)
RSOH
MSOH
PayloadPayload
RSOH
MSOH
Parity bytes providing a means to supervise the transmission quality of a life STM-N signal !
PayloadAU-PTR
08.04.23 09:03 The World of Synchronous Networks 79
Parity Supervison Procedure
Tra
nsm
it S
ide
BIP-8 B1
frame nframe n+1
08.04.23 09:03 The World of Synchronous Networks 80
Parity Supervison Procedure
Tra
nsm
it S
ide
BIP-8 B1
frame nframe n+1
BIP-8 B1Comparisonwith the Tx side value
Rec
eive
Sid
e
frame n+1 frame n
recalculation at Rx side
08.04.23 09:03 The World of Synchronous Networks 81
How to Built a Parity Byte ?
Bit interleaved data field structure of the area covered Field width: BIP-24: 24 bits (B2) BIP-8: 8 bits (B1, B3) BIP-2: 2 bits (V5)
Column by column parity check for even numbers of "1"
BIP-24801
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1 0 1 1 0 0 0 1 1 1 0 1 0 1 0 0 0 1 1 0 0 1 1 1 0 0 1 0 1 0 1 0 0 1 1 1 1 0 1 0 1 1
0 0 1 0 0 0 1 1 0 1 1 1 1 0 1 0 1 0 1 1 0 1 1 1
1 1 0 1 0 1 0 1 1 0 1 1 0 1 0 0 1 1 1 0 0 1 0 11 0 0 1 0 0 0 0 1 0 1 0 0 0 0 0 1 0 1 0 1 0 0 0
1
23
Byte 1 Byte 2 Byte 3
even numbers of "1"
Example: 24 bit interleaved parity check (BIP-24)
08.04.23 09:03 The World of Synchronous Networks 82
SDH MAINTENANCE INTERACTIONS
LOS/LOFRS-TIM
BIP Err.
"1"AIS
MS-AIS "1"
MS-BIP Err.
MS-REI
MS-RDI
AU-AIS
AU-LOP
AIS
"1"
HP-UNEQ
HP-TIM
HP-BIP Err.
HP-REI
HP-RDI
"1"AIS
TU-AIS
TU-LOP
LOM
HP-PLM
LP-UNEQ
LP-TIM
LP-BIP Err.
LP-REILP-RDI
LP-PLM
"1"
"1"
"1"
AIS
AIS
RegeneratorSection
MultiplexSection
Higher OrderPath
Lower OrderPath
(J0)
(B1)
(K2)
(B2)
(M1)
(K2)
(C2)
(J1)
(B3)
(G1)
(G1)
(H4)
(C2)
(V5)
(J2)
(V5)
(V5)
(V5)
(V5)
08.04.23 09:03 The World of Synchronous Networks 83
LOS Drop of incomming optical power level causes BER of 10-3 or worseOOF A1, A2 incorrect for more than 625 usLOF If OOF persists of 3msB1 Error Mismatch of the recovered and computed BIP-8MS-AIS K2 (bits 6,7,8) =111 for 3 or more framesB2 Error Mismatch of the recovered and computed BIP-24MS-RDI If MS-AIS or excessive errors are detected, K2(bits 6,7,8)=110MS-REI M1: Binary coded count of incorrect interleavedbit blocksAU-AIS All "1" in the entire AU including AU pointerAU-LOP 8 to 10 NDF enable or 8 to 10 invalid pointersHP-UNEQ C2="0" for 5 or more framesHP-TIM J1: Trace identifier mismatchHP-SLM C2: Signal label mismatchHP-LOM H4 values (2 to 10 times) unequal to multiframesequence
B3 Error Mismatch of the recovered and computed BIP-8HP-RDI G1 (bit 5)=1, if an invalid signal is received in VC-4/VC-3HP-REI G1 (bits 1,2,3,4) = binary coded B3 errors
Maintenance Signal Defenitions (1)
08.04.23 09:03 The World of Synchronous Networks 84
TU-AIS All "1" in the entire TU incl. TU pointerTU-LOP 8 to 10 NDF enable or 8 to 10 invalid pointersLP-UNEQ VC-3: C2 = all "0" for >=frames;
VC-12: V5 (bits 5,6,7) = 000 for >=5 framesLP-TIM VC-3: J1 mismatch; VC-12: J2 mismatchLP-SLM VC-3: C2 mismatch; VC-12: V5 (bits 5,6,7) mismatchBIP-2 Err Mismatch of the recovered and computed BIP-2 (V5)LP-RDI V5 (bit 8) = 1, if TU-2 path AIS or signal failure receivedLP-REI V5 (bit 3) = 1, if >=1 errors were detected by BIP-2LP-RFI V5 (bit 4) = 1, if a failure is declared
Abbreviations:
AU Administration unitHP High path
LOF Loss of frameLOM Loss of miltiframeLOP Loss of pointerLOS Loss of signal
LP Low pathOOF Out of frameREI Remote error indication (FEBE)RDI Remote defect indication (FERF)RFI Remote failure indicationSLM Signal label mismatch
TIM Trace identifierTU Tributary unitUNEQ UnequippedVC Virtual C container
Maintenance Signal Definitions (2)
08.04.23 09:03 The World of Synchronous Networks 85
ES Errored Second Second with> 1errored block
SES Severely Errored Second Second with > 30% errored blocks or > 1 defect
BBE Background Block Error Errored block, not occuring aspart of SES
ITU-T G.826ITU-T G.826ITU-T G.826ITU-T G.826
ES Errored Second Second with > 1 bit error
SES Severely Errored Second Second with BER > 1 x 10E-3
ITU-T G.821ITU-T G.821ITU-T G.821ITU-T G.821
UAS Unavailable Seconds:
Time10 sec 10 sec
< 10sec
Unavailable SecondsUnavailable Seconds
Unavailabilitydetected
Availabilitydetected
Performance Parameter
08.04.23 09:03 The World of Synchronous Networks 86
Jitter and Wander
08.04.23 09:03 The World of Synchronous Networks 87
0 1 2 3 4 5 6 7 8 9 . . .
Time Line
1 0 1 1 0 1 0 0 1 10 0Bit Sequence
1 UI
Ideal Signal (NRZ)
Actual Signal(with Jitter
and Wander)
Phase Variations (Jitter or Wander) in a Digital Transmission System
Jitter and Wander Definitions
08.04.23 09:03 The World of Synchronous Networks 88
• Interference signals
• Pattern dependent jitter
• Phase noise
• Delay variation
• Stuffing and wait time jitter
• Mapping jitter
• Pointer jitter
Sources of Jitter and Wander
08.04.23 09:03 The World of Synchronous Networks 89
Pattern
Clock
SignalInput
Ext. Reference Clock Input (Wander Measurement)
ClockInput
N
1
V
V
Pattern-ClockConverter
FrequencyDivider
Phase Detector
Phase Detector
~ 1 Hz
Filters
HP LP
Peak-to-PeakDetector
Low Pass Filter VCO
JitterandWander
Reference Clock Generator (PLL)
ResultEvaluation
Jitter and Wander Measurement Method
08.04.23 09:03 The World of Synchronous Networks 90
Amplitude / dB
Frequency / Hz10 Hz
STM-1: 500 Hz 65 kHz 1.3 MHzSTM-4: 1 kHz 250 kHz 5 MHzSTM-16: 5 kHz 1 MHz 20 MHz
HighFrequency
Jitter
Jitterincluding
lowerFrequency
Components
TotalJitter
Wander
Values according to ITU-T Rec. G.825 and G.813
Max. Jitter Amplitude: 1,5UI 0,15UI
Jitter Measurement Filters
08.04.23 09:03 The World of Synchronous Networks 91
JitterAmplitude
(PP)
Measurement Period
Jitter / UIpp
Time
Definition of Jitter Peak-to-Peak Amplitude
08.04.23 09:03 The World of Synchronous Networks 92
Network output jitter (G.825)
Network element output jitter (G.783, G.813)
Jitter transfer function (G.958)
Jitter and Wander tolerance (G.825, G.813)
Jitter and Wander Measurements
08.04.23 09:03 The World of Synchronous Networks 93
Wander Long-term timing variation (below 10 Hz)
TIE "Time Interval Error"
MTIE "Max. Time Interval Error"
TDEV "Time Deviation", timing variation as a function of integration time. Provides information about the spectral content.
TVAR "Time Variation", square of TDEV
ADEV "Allen Deviation"
MADEV "Modified Allen Deviation"
Definitions specified in ITU-T Rec. G.810
WANDER Definitions
08.04.23 09:03 The World of Synchronous Networks 94
MTIE
Observation Period
Start End
Wander / UI
Time
Slope representing
Frequency Offset
TIE at t End
TIE max
TIE min
Tim
e va
riat
ion
ag
ain
st r
efer
ence
TIE and MTIE Definition
08.04.23 09:03 The World of Synchronous Networks 95
Results (MTIE) compared to Standards
08.04.23 09:03 The World of Synchronous Networks 96
Network resilience
08.04.23 09:03 The World of Synchronous Networks 97
Linear Protection (G.783)
W
P
W
P
W
W
P
1 + 1 Protection scheme
1 : 1 Protection scheme
1 : N Protection scheme
08.04.23 09:03 The World of Synchronous Networks 98
Linear Protection (G.783)
W
P
W
P
W
W
P
1 + 1 Protection scheme
1 : 1 Protection scheme
1 : N Protection scheme
08.04.23 09:03 The World of Synchronous Networks 99
Unidirectional and Bidirectional Rings
ADM
ADM
ADM
ADM
A
B
Traffic A -> B
Traffic B -> A
Unidirectional Ring
traffic between A-B uses the entire length of ring
Bidirectional Ring- use the shorter or longer path- increase number of paths- short path : traffic long path : protection
ADM
ADM
ADM
ADM
A
B
Traffic A -> B
B -> A
longer path
08.04.23 09:03 The World of Synchronous Networks 100
Unidirectional Path-Switched Ring
Tributary
Tributary
A
C
BF
D
E
Fiber 2 : unidirectional
Fiber 1 : unidirectional
08.04.23 09:03 The World of Synchronous Networks 101
Unidirectional Path-Switched Ring
Tributary
Tributary
A
C
BF
D
E
Fiber 2 : unidirectional
Fiber 1 : unidirectional
08.04.23 09:03 The World of Synchronous Networks 102
Unidirectional Path-Switched Ring
Tributary
Tributary
A
C
BF
D
E
Fiber 2 : unidirectional
Fiber 1 : unidirectional
08.04.23 09:03 The World of Synchronous Networks 103
Unidirectional Line-Switched Ring
Tributary
Tributary
A
C
BF
D
E
Protection
Working
Working
08.04.23 09:03 The World of Synchronous Networks 104
Unidirectional Line-Switched Ring
Tributary
Tributary
A
C
BF
D
E
Protection
Working
Working
08.04.23 09:03 The World of Synchronous Networks 105
Unidirectional Line-Switched Ring
Tributary
Tributary
A
C
BF
D
E
Protection
Working
Working
08.04.23 09:03 The World of Synchronous Networks 106
Two fiber Bidirectional Line-Switched Ring (BLSR)
Tributary
A
BF
C
D
E Tributary
Fiber 1
Fiber 2
workingprotection
08.04.23 09:03 The World of Synchronous Networks 107
Tributary
A
BF
C
D
E Tributary
Fiber 1
Fiber 2
Two fiber Bidirectional Line-Switched Ring (BLSR)
workingprotection
08.04.23 09:03 The World of Synchronous Networks 108
Two fiber Bidirectional Line-Switched Ring (BLSR)
Tributary
A
BF
C
D
E Tributary
Fiber 1
Fiber 2
workingprotection
08.04.23 09:03 The World of Synchronous Networks 109
Tributary
A
BF
C
D
E Tributary
Prot.Fiber 3 + 4
Working Fiber 1 + 2
Four fiber Bidirectional Line-Switched Ring (BLSR)
08.04.23 09:03 The World of Synchronous Networks 110
Four fiber Bidirectional Line-Switched Ring (BLSR)
Tributary
A
BF
C
D
E Tributary
Prot.Fiber 3 + 4
Working Fiber 1 + 2
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Four fiber Bidirectional Line-Switched Ring (BLSR)
Tributary
A
BF
C
D
E Tributary
Prot.Fiber 3 + 4
Working Fiber 1 + 2
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Four fiber Bidirectional Span-Switched Ring
Tributary
A
BF
C
D
E Tributary
Prot.Fiber 3 + 4
Working Fiber 1 + 2
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Four fiber Bidirectional Span-Switched Ring
Tributary
A
BF
C
D
E Tributary
Prot.Fiber 3 + 4
Working Fiber 1 + 2
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Four fiber Bidirectional Span-Switched Ring
Tributary
A
BF
C
D
E Tributary
Prot.Fiber 3 + 4
Working Fiber 1 + 2
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TMN in SDH networks
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Network Management
Basic tasks of network management:
Administrative functions:
Operation: Network supervising (anomalies, defects)Network linking (reserve links, additional links)
Maintenance: Identifing and elimination of impairments
Planning and commissioning: Network configuration
Operative functions: Supervision of network functionsRepairInstallationSelf test
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TMN Overlay
CC CC
Central OS
Local OS
Q
Q
Q
Q ECC
ADM
AD
M
AD
M
ADM
Q ECC
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PerformanceFaultsConfigurationAccountingSecurity
Management of :
DXC DXC
Central OS
Local OS
XX
Q3
Q3
Q3
Q ECC
ADM
AD
M
AD
M
ADM
QECC
Central OS
NEManager
NEManager
Q3
Data Communication Network : X.25, ISDN, LAN
Telecommunication Management Network (TMN) Overlay
STM-N
STM-N STM-N
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TMN Reference Configuration
Operating System
OS
Mediation Device
MD
Network Element
NE
Data Communication Network
DCN
Network Element
NE
F
F
F
Q3
Q3
Q2 or Q1
Qx
Q3
Workstation
Workstation
Workstation
MD: Conversion between different interfaces(Information Conversion Function ICF:manufacturer-specific information model ->operator specific information model)
Local Communication Network
LCN
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Interoperability in TMN
QMonitor provides easy adaptation to the interface
(autoconfiguration)
decoding of protocols and management information
automatic detection of errors in management information
SDH/SONET Qecc access with transmission analyzers (e.g. ANT-20)
QMonitor based on DominoWANDominoLAN DA-30
TMNOperations
System
TMNOperations
System
Qecc Qecc
Qecc
Q3
Q3
XX Interoperability problems because of– multi vendor networks
– heterogenous technology
– different standards for protocols and management information
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SDH Benefits
Reduced equipment costsmulti vendor compatibility
Lower maintenance costsbuilt-in defect and anomaly monitoring
Future proof equipmentSDH is the physical layer for BISDN
Efficient drop / insert facilitiesADM (add&drop multiplexers), DXC (digital cross connectors)
TMN capabilitiesBuilt-in DCN (data comm. network), DCC/ECC
More flexibility in provision of servicesadding transmission capacity by routing on demand
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Pirelli : WaveMux 320032 x OC-48 channels80Gbit/s over 1200km
40 x OC-48 channels100Gbit/s over 600km
Ciena :
There may not be a near term need, but this is the direction that networking will take next for 3 or 4 years.
Ryan, Hunkin, Kent Consulting '96
Future Trends - WDM Systems
Current Systems : 4, 8, 16 x OC-48 (MCI, Sprint)
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Future Trends - Optical ComponentsFuture Trends - Optical Components
ADM
Optical D&I
Local Traffic2Mbit/s, DS-3, STM-1
WDM WDM
STM-N,OC-N
STM-N,OC-N
Extract selectively Minimize need for demultiplexing
entire bandwidth
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STM-16c VC2-5c PoS
STM-64
DWDM
Larger Capacity
Optical Networks
Additional Mappings
FutureTrendsin Synchronous Technology
TMN Q3 Worldwide
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Let‘s summarize !
•Please name the PDH bitrates !
•Please explain „stuffing“ !
•When will „stuffing“ be applied ?
•What is the reaction of a Network element after an „LOS“ alarm ?
•What is the meaning of an „LOF“ alarm ?
•Is it possible to drop an 2Mbit/s signal out of an 140Mbit/s line ?
•Why not ?
•Please name the SDH bitrates !
•Explain the way an PDH signal is integrated in an STM-1 !
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Let‘s summarize !
•Please name the different sections of an SDH connection !
•What is a parity byte ?
•Please explain the way to build a parity byte !
•Which parity bytes do you know ?
•Which overhead bytes are used for data communication ?
•What is a „pointer“ ?
•What is a „pointer“ used for ?
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Let‘s summarize !
•Please name the SDH network elements !
•What are they used for ?
•Please explain how a synchronization network looks like !
•What is a holdover mode ?
•Which byte is used to transport an HP-UNEQ ?
•Please explain „Jitter“ and „Wander“ !
•How can jitter be defined ?
•Please explain the terms TIE and MTIE ?
•Please explain the term TDEV ?
•Explain the possibilities to synchronize a NE !
08.04.23 09:03 The World of Synchronous Networks 128
Let‘s summarize !
•Please name the main Jitter and Wander measurements !
•Explain these measurements !
•Please explain the methods of linear protection !
•What kind of ring structures do you know ?
•Please explain „DWDM“ !
•What are the the advantages of a TMN controlled network ?
•How is the TMN interface called ?