Training New SDH All
Transcript of Training New SDH All
NNewewSSDHDHTTechnologyechnologyTTechnologyechnologySSeminareminar
November 2002November 2002
Agenda� Market & Technology Drivers� New SONET/SDH - Overview� Virtual Concatenation (VC) � Link Capacity Adjustment Scheme (LCAS)� Generic Frame Procedure (GFP)
Page 2
� Generic Frame Procedure (GFP)� Acterna’s Solution � Testing Tasks� Appendix
The situation
The economic situation in the Telecom Industry has changed...
Page 3
...and so has the technological approach to meet new challenges!
The future - as seen in 2000
SONET/SDHNetwork
SONET/SDH for VOICE
Services
Seen Status
Future Network
Page 4
� One new network for both applications!
LAN
Fully RoutedOptical IPNetwork
Optical IP for DATA
Services
Future Network
The Status Today
� SDH/ SONET - is the deployed technology in the core network with huge investments in capacity!
� Ethernet - is the dominant technology of choice at LANs and well known at all enterprises worldwide!
� Data traffic is still growing, but only at a slower
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is still growing, but only at a slower speed than expected
� All network topologies focusing on a IP/Ethernet ONLY approach are shifted to long-term future.
� The future today:
� Bring SONET/SDH and Ethernet together!
New Customer Applications
Virtual Private Network(VPN)
Core Network
LAN LANPC
ServerEthernet
Page 6
Storage Area Network (SAN)
Edge Network
Core Network
Storage Server
SONET/SDH
Fibre Channel
Bringing it all together?
CoreOperator wants:• Reduce Opex• Realize revenue-earning services• Use bandwidth of Core Network X
Customer expects:• QoS & BW at low costs• Native Data Interfaces• � Use & Improve what he knows!
LAN
Voice
Page 7
Edge
• Use bandwidth of Core Network• Low investment � immediate ROI• � Close the edge bottleneck!
X
SAN
Solution:Make SONET/SDH flexible & data aware at the edge and
still use the existing core!
Edge
Manufacturer needs:• ...to develop solutions...fast!
Worldwide Optical Network Equipment Market
10,000.0
12,000.0
14,000.0
16,000.0
18,000.0
Mill
ions
of U
.S.
Dol
lars
NewGen
Traditional SDH/SONET
Page 8
0.0
2,000.0
4,000.0
6,000.0
8,000.0
1999 2000 2001 2002 2003 2004 2005 2006
Year
Mill
ions
of U
.S.
Dol
lars
Traditional SDH/SONET
Source: Gartner
Mass market Carrier Class market
Asynchronous Synchronous
Ethernet vs. SONET/SDH
Ethernet SONET / SDH
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Dynamic Bandwidth Fixed Bandwidth
Connection less Connection oriented
Best Effort Service High Quality of Service
How to solve all these challenges?
NNewewSSDH / DH / SSONETONET
OOverviewverviewOOverviewverview
Going into Details
Campus A
Ethernet
SONET/ SDHSONET/
SDH
Campus B
EthernetFICON
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Optical CoreOptical Core
NetworkNetwork
Remote Servers
Storage Servers
Fibre Channel
SONET/SDHSONET/SDH
DWDMDWDM
SONET/ SDH
Let‘s zoom in!Core NE
Edge NE
SO
NE
T M
UX
/DE
MU
X
Nat
ive
Inte
rfac
es
New SONET/SDH at the Edge
?VC LCASGFPEthernet
Ficon
Edge CoreAdaptation
Customer Operator
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SONET/SDH
SO
NE
T M
UX
/DE
MU
X
Nat
ive
Inte
rfac
es ?
That’s “ New SONET/SDH “
VirtualConcatenation
Link Capacity
Adjustment Scheme
Generic Frame
Procedure
LAPS
Ficon
Escon
Fibre Channel
Customer needs Ethernet
Typical Ethernet Traffic
Connections
100
75
Mbit/s
Problem: How can we efficiently transport Ethernet over an existing SONET/SDH network?
Customer 3 = 100M
Customer 2 = 60M
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Connections
25
50
time1 2 3 4
Ethernet Packet
Example: For 10M available SDH - Containers are...
VC-12 ...too small !
2.176 Mbit/s
VC-3 ... inefficient20%
48.38 Mbit/s
OR
Customer 1 = 10M
SDH Line Rates
10 M
Transport 10M Ethernet over SDH?
C-11 1.600 Mbit/sC-12 2.176 Mbit/sC-2 6.784 Mbit/sC-3 48.384 Mbit/sC-4 149.760 Mbit/s
SDH Payload Sizes
Standard Containers are inefficient!
?5x
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C-4-4c 0.599 Gbit/sC-4-16c 2.396 Gbit/sC-4-64c 9.584 Gbit/sC-4-256c 38.338 Gbit/s
Contiguous ConcatenationContiguous Concatenationonly large containers!
Can’t 5 x VC -12 be concatenated?
VVirtualirtualCConcatenationoncatenation
VC-n-X v
Concatenation?Contiguous Concatenation� Offers concatenated payloads in fixed, large steps� One towing truck (POH) for all containers� All containers are on one path thru the network
C4 C4 C4 C4
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C-4-4c 599.040 Mbit/sC-4-16c 2.396 Gbit/sC-4-64c 9.584 Gbit/sC-4-256c 38.338 Gbit/s
Contiguous ConcatenationVirtual Concatenation� Offers structures in a fine granularity� Every container has its own towing truck (POH)� Every container might take a different path
VC-4-4v
VC-4 #1VC-4 #2VC-4 #3VC-4 #4
VC-4-4c
RSOH
AU-4 Pointer
STM-N
CC: VC-4-Xc ContainerOverhead N x 9 bytes Payload N x 261 bytes
J1
B3
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MSOH
VC-4-Xc, where X=4, 16, 64, 256
VC-4-Xc
X x 261 bytes
X -11
C2
G1
H4
F3
K3
N1
C-4-XcF
ixed
Stu
ff
B3
F2
RSOH
AU-4 Pointer
STM-N
VC: VC-4-Xv ContainerOverhead N x 9 bytes Payload N x 261 bytes
J1
J1
B3
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MSOH
VC-4-Xv, where X = 1..256
261 bytes1
VC-4
J1
C2
G1
H4
F3
K3
N1
B3
F2VC-4
C2
G1
H4
F3
K3
N1
B3
F2VC-4
C2
G1
H4
F3
K3
N1
B3
F2
X frames
SDH ConcatenationSTM-16 with VC-4-4c
RSOH
AU-4 Pointer
MSOH
VC-4-1 VC-4-2
VC-4-5 VC-4-6
VC-4-11 VC-41-2
VC-4-15 VC-4-16
VC-4-3 VC-4-4
VC-4-7 VC-4-8
VC-4-9 VC-4-10
VC-4-13 VC-4-14
Contiguousconcatenation
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RSOH
AU-4 Pointer
MSOH VC-4-#2
VC-4-#1
VC-4-1 VC-4-2
VC-4-3 VC-4-4
STM-4 with VC-4-2v
Virtualconcatenation
VCG = Virtual Container Group
RSOH
AU-4 Pointer
MSOH
SDH Concatenation2x STM-16 with VC-4-11v
VC-4-1 VC-4-2
VC-4-5 VC-4-6
VC-4-11 VC-41-2
VC-4-15 VC-4-16
VC-4-3 VC-4-4
VC-4-7 VC-4-8
VC-4-9 VC-4-10
VC-4-13 VC-4-14Virtual
Concatenation
spread across
#1
#2
#3 #4#10
#8 #9
#11
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spread acrossTWO frames
VCG = Virtual Container Group
RSOH
AU-4 Pointer
MSOH
VC-4-1 VC-4-2
VC-4-5 VC-4-6
VC-4-11 VC-41-2
VC-4-15 VC-4-16
VC-4-3 VC-4-4
VC-4-7 VC-4-8
VC-4-9 VC-4-10
VC-4-13 VC-4-14
#6
#5
#7
� Virtual Concatenation is standardized� with SONET containers (ANSI T.105) or� SDH containers (ITU-T G.707)
� Virtual Concatenation provides� a scheme to build right-sized SONET/SDH
Virtual Concatenation (VC or Vcat)
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� a scheme to build right-sized SONET/SDH containers
� Virtual Concatenation offers� a very fine granularity
VC Nomenclature
VC-nVirtual Container n
n=4, 3, 2, 12, 11
-XNumber of
virtually
vIndictor for
Virtual
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n=4, 3, 2, 12, 11
Defines the type of virtual containers, which will be virtually concatenated.
virtuallyconcatenated
containers
All X Virtual Containers form together the
“Virtual Concatenated Group” (VCG)
Virtual Concatenation
v = virtual concatenationc = contiguous concatenation
Virtual Concatenated Group (VCG) of X VC-n containe rs!
High and Low Order VC
VC-4
High Order Virtual Concatenation• refers to virtually concatenated...
VC-3 containers
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VC-11
VC-12
VC-2
Low Order Virtual Concatenation• refers to virtually concatenated...
containers
VCG Granularity
MinimumVCGs:VC-4-1v Payload Size 149,76 Mbit/sVC-4-2v Payload Size 299,52 Mbit/s
VC-4-Xv Granularity
VC-4
Example High Order VC:VC-4 Container Size 150,3 Mbit/sVC-4 Payload Size 149,76 Mbit/s
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VCG Payload Capacity
Maximum
VC-4-2v Payload Size 299,52 Mbit/s
VC-4-7v Payload Size 1048,3 Mbit/s
VC-4-256v Payload Size 38338 Mbit/s
Minimum
VCG GranularityVCGs:VC-12-1v Payload Size 2,176 Mbit/sVC-12-2v Payload Size 4,352 Mbit/s
VC-12-Xv GranularityExample Low Order VC:VC-12 Container Size 2,240 Mbit/sVC-12 Payload Size 2,176 Mbit/s
VC-12
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VC-12-2v Payload Size 4,352 Mbit/s
VCG Payload Capacity
Maximum
VC-12-5v Payload Size 10,88 Mbit/s
VC-12-64v Payload Size 139,26 Mbit/s
VC Granularity and max. Capacity
Nomenclature Granularity Max. Capacity
VC-4 –n v 149 M - 38.3G
VC-3 –n v 48 M - 12.7 G
VC-2 –n v 6.8 M - 434 M
VC-4
VC-3
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VC-2 –n v 6.8 M - 434 M
VC-12 –n v 2.2 M - 139 M
VC-11 –n v 1.6M - 102 M
VC-2
VC-12
VC-11
Maximum Concatenation: = 256 containersMax. Capacity: = 256 x granularity
VC Rate Efficiencies
Ethernet (10M) VC3 �20% VC-12-5v � 92%
Fast Ethernet (100M) VC-4 �67% VC-12-46v � 100%
Data Rates Efficiency w/o VC using VC
ESCON (200M) VC-4-4c �33% VC-3-4v � 100%
Fibre Channel (800M) VC-4-16c �33% VC-4-6v � 89%
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100M Ethernet STM-1= 64 x VC-12
VC-12-5v
VC-12-46v
2x 10M EthernetVC-12-5v
8x E1 Services
Example:
More services integrated- by using VC!
Gigabit Ethernet (1G) VC-4-16c �42% VC-4-7v � 85%
Transporting Concatenated SignalsContiguous Concatenation
VC-4-4c
C-4 C-4
C-4 C-4
C-4 C-4
C-4 C-4 NENE
One Path
C-4 C-4
C-4 C-4
Core Network
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VC-4-2v
Virtual Concatenation
VC-4 #2
VC-4 #1
VC-4 #1
Path 2
Path 1
VC-4 #2
Differential Delay
VC-4 #2
VC-4 #1
VC-4 #2
VC-4 #1
VC-4-4cCore Network
VVirtualirtualCConcatenationoncatenation
Virtual Concatenated Groups
Answer:The containers do not know it!That’s the job of the network management!
Question:How does a container know that it belongs to a VCG?
Question:Which containers can belong to the same group?
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Which containers can belong to the same group?
Answer:They must all start at one port!And they must all end at one port!
A
B
A
B
A A
VC-4
Virtual Container IndicatorProblem:How to distinguish between VCG members of one group?
SQ=0
Solution:Give each member an individual “number plate”!� Sequence Indicator (SQ)
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VC-4
VC-4
VC-4
SQ=1
SQ=2
SQ=3
Result: VCG members can now be distinguished and sorted!
Time Stamp Mechanism
VC-4 SQ=0
Problem:How do we know that members arriving together started together?
Solution:Give each VCG an individual number� Frame Counter (FC)
SQ=0SQ=0 SQ=0SQ=0 SQ=0SQ=0 SQ=0 SQ=0SQ=0SQ=0
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VC-4
VC-4
VC-4
VC-4
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 1
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 1
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 2
SQ=0
SQ=1
SQ=2
SQ=3
FC = 1
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 2
SQ=0
SQ=1
SQ=2
SQ=3
FC = 3
SQ=0
SQ=1
SQ=2
SQ=3
Storage
VCG Realignment
DemappingArrival
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = 2
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = 2
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = 2
SQ = 1
SQ = 0FC = 3
SQ=2 is one frame late!
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SQ = 1FC = max
SQ = 3FC = max
SQ = 1FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 2FC = max
SQ = 3FC = 0
SQ = 1FC = max
SQ = 2FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = max
SQ = 2FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = max
SQ = 2FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = 2
SQ = 2FC = 1
SQ = 3FC = 2
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = 2
SQ = 2FC = 1
SQ = 3FC = 2
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = 2
SQ = 2FC = 1
SQ = 3FC = 2
SQ = 1FC = 3
SQ = 3FC = 3
SQ = 2FC = 2
Stop
Differential DelayProblem:Each individual container of a VCG might take a different route through the network - Delay?
Propagation Delay (optical fiber):is approximately 5 µs/km � 1000km extra path length = 5ms Differential Delay� Once around the earth Extra (42.000km) = 210ms DD
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Result: Differential Delay� Different physical path lengths will result in different path delays for individual containers!
� Once around the earth Extra (42.000km) = 210ms DD
Solution:A container storage & realignment process is necessaryto compensate for differential delay!
How the group starts:
Differential Delay ExampleExample:VC-4-2v group routed over TWO paths• Container SQ=0 � 1000km � 5.0 ms propagation time• Container SQ=1 � 1075km � 5.375 ms propagation time� Differential Delay = 5.375ms-5.0ms = 0.375ms (=3 frames)
SQ = 0FC = 0
SQ = 0FC = 0
SQ = 0FC = 1
SQ = 0FC = 0
SQ = 0FC = 1
SQ = 0FC = 2
SQ = 0FC = 0
SQ = 0FC = 1
SQ = 0FC = 2
SQ = 0FC = 3
SQ = 0FC = 0
SQ = 0FC = 1
SQ = 0FC = 2
SQ = 0FC = 3
SQ = 0FC = 4
Page 35
Network
How the group arrives:
Storage Demapping
FC = 0
SQ = 1FC = 0
FC = 0
SQ = 1FC = 0
FC = 1
SQ = 1FC = 1
FC = 0
SQ = 1FC = 0
FC = 1
SQ = 1FC = 1
FC = 2
SQ = 1FC = 2
FC = 0
SQ = 1FC = 0
FC = 1
SQ = 1FC = 1
FC = 2
SQ = 1FC = 2
FC = 3
SQ = 1FC = 3
FC = 0
SQ = 1FC = 0
FC = 1
SQ = 1FC = 1
FC = 2
SQ = 1FC = 2
FC = 3
SQ = 1FC = 3
FC = 4
SQ = 1FC = 4
SQ = 0FC = 0
SQ = 0FC = 0
SQ = 0FC = 1
SQ = 0FC = 0
SQ = 0FC = 1
SQ = 0FC = 2
SQ = 0FC = 0
SQ = 1FC = 0
SQ = 0FC = 1
SQ = 0FC = 2
SQ = 0FC = 3
SQ = 0FC = 0
SQ = 1FC = 0
SQ = 1FC = 1
SQ = 0FC = 1
SQ = 0FC = 2
SQ = 0FC = 3
SQ = 0FC = 4
SQ = 0FC = 1
SQ = 1FC = 1
SQ = 0FC = 2
SQ = 1FC = 2
SQ = 0FC = 3
SQ = 0FC = 4
SQ = 0FC = 5
SQ = 0FC = 2
SQ = 1FC = 2
SQ = 0FC = 3
SQ = 1FC = 3
SQ = 0FC = 4
SQ = 0FC = 5
SQ = 0FC = 6
Delay TimesProblem:What’s the maximum differential delay time?
FC = 0
SQ=0
SQ=1
FC = 1
SQ=0
SQ=1
FC = max
SQ=0
SQ=1
FC = 2
SQ=0
SQ=1
No DelayBoth containers
arrive at the
Page 36
FC = 0
SQ=1FC = 1
SQ=1FC = max
SQ=1FC = 2
SQ=1
FC = 0
SQ=0FC = 1
SQ=0FC = max
SQ=0FC = 2
SQ=0
FC = 0
SQ=1FC = 1
SQ=1FC = max
SQ=1FC = max-1
SQ=1
Total Differential Delay Time (s) = 1 x Frame Repetition Rate
arrive at the same time!
Container SQ=1arrives with
ONE frame delay
Max. Delay Compensation
FC = 0
SQ=0FC = 1
SQ=0FC = max
SQ=0
FC = 0
SQ=1FC = 1
SQ=1FC = max
SQ=1
Maximum Differential Delay Time =
FC=max frames delay of SQ=1
FC = 0
SQ=1
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Maximum Differential Delay Time = FC = max x Frame Repetition Rate
FC = 0
SQ=0FC = 1
SQ=0FC = max
SQ=0FC = 2
SQ=0
FC = 0
SQ=1FC = 1
SQ=1FC = max
SQ=1FC = 2
SQ=1
Member SQ=0 and SQ=1 did not start at the same timePayload is LOST!
Too much DelayFC = max+1 frames
VCG is out of synch!
Storage Capacity
Storage Example - worst case
SQ = 1FC = 0
SQ = 0FC = 0
SQ = 1FC = 1
SQ = 0FC = 1
SQ = 1FC = 2
SQ = 0FC = 2
SQ = 1FC = max-1
SQ = 0FC = max-1
SQ = 1FC = max
SQ = 0FC = max
SQ = max arrives the maximum Frame Counter value to o late!
SQ = 1FC = 0
SQ = 0FC = 0
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Stop
FC = 0
SQ = max-1FC = 0
FC = 1
SQ = max-1FC = 1
FC = 2
SQ = max-1FC = 2
FC = max-1
SQ = max-1FC = max-1
FC = max
SQ = max-1FC = maxSQ = max
FC = 0
Max. Storage Capacity = Size of one VC-n container xNumber of group members x
Maximum frame counter value x
FC = 0
SQ = max-1FC = 0
SQ = maxFC = 0
Storage SpaceProblem:How much storage space would a new network element require?
Solution:It depends on the maximum differential delay, which the network element should be able to compensate for!
� Maximum Differential Delay in ITU -T = 512ms
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Necessary Storage Capacity =
VC Container Capacity (Mbit/s) *
Number of Members in one VCG *
Maximum Differential Delay (s) *
� Maximum Differential Delay in ITU -T = 512ms
105Mbit
VVirtualirtualCConcatenationoncatenation
Where are the VC bytes?
•Carried in one bit in K4-Byte• 32 frame Multi-Frame
High Order VC Low Order VC
• Information in H4 Byte• 16 frame Multi-Frame
B3C2
J1VC-3 / VC-4
out of J2N2
V5 VC-2 / VC-11/VC-12out of
VC-2-Xv / VC-11-Xv /VC-12-Xv
Page 41
F2H4F3K3
C2G1
N1
out ofVC-3-Xv / VC-4-Xv N2
K4
VC-2-Xv / VC-11-Xv /VC-12-Xv
What’s a multi-frame?
J2N2K4
V5 VC-2 / VC-11/VC-12out of
VC-2-Xv / VC-11-Xv /VC-12-Xv
Low Order VCHow to build a multi-frame control packet?• Filter from each K4 byte only bit no. 2• Store bit no. 2• After 32 VCs, one Virtual Concatenation • control information was received.
K4
b2Filter
32x K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
Page 42
Frame Counter
(FC)
Sequence Indicator
(SQ)Reserved...
1
b2Filter
2
b2
3
b2
4
b2
5
b2
6
b2
7
b2
8
b2
9
b2
11
b2
12
b2
13
b2
14
b2
15
b2
16
b2
10
b2
17
b2
18
b2
19
b2
20
b2
21
b2
22
b2
23
b2
24
b2
25
b2
27
b2
28
b2
29
b2
30
b2
31
b2
32
b2
26
b2
...for LCAS
High Order VC - H4 byte
0123456
MFI1 MFI2
H4 Byte Multi-FrameBit 1 - 4 Bit 5 - 8
Reserved “0000”Reserved “0000”
Reserved “0000”
Reserved “0000”
Reserved “0000”
MFI1 (bit 1-4)
0 0000 1000 0100 1100 0010 1010 011
MFI2 (bit 1-4)MFI2 (bit 5-8)
8 bit
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6789
101112131415
n
Reserved “0000”Reserved “0000”
Reserved “0000”Reserved “0000”Reserved “0000”
Reserved “0000”Reserved “0000”
Reserved “0000”
0 0110 1111 0001 1001 0101 1101 0011 1011 0111 111
SQ (bit 1-4)SQ (bit 5-8)
8 bit
Time for transmitting ONE multi-frame: 16 byte x 125µs = 2ms
MFI 1 - Multi Frame Indicator 14 bits - Counter incremented at each individual frameOne MFI1 multi-frame = 16 framesCounts from 0 to 15
MFI 2 - Multi Frame Indicator 28 bits - Counter incremented every 16 frames - after a complete
MFI1 multi-frame
High Order VC - H4 byte
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Counts from 0 to 255
High Order VC Frame Counter:MFI1 x MFI2 = 16 x 255 = 4096Max. tolerable Differential Delay = 4096 x 125 µs = 512ms
SQ - Sequence Indicator8 bits - Transmitted once every MFI 1 multi-frameMax. number of High Order VCG members = 256
K4 byte (VC -2, 11, 12)
bit 1:Extended Signal label - 32 frame multi-frame
bit 2: Low order Virtual concatenation
1 72 3 4 5 6 8 9 1210 11 13 1914 15 16 17 18 20 21 2422 23 25 3126 27 28 29 30 32
ReservedMFAS = Multiframe
alignment bits0111 1111 110
Extended Signal Label 0
1 72 3 4 5 6 8 9 1210 11 13 1914 15 16 17 18 20 21 2422 23 25 3126 27 28 29 30 32
Low Order VC - K4 byte
Page 45
bit 2: 32 frame MF should be in phase with b1 multi-frame
1 72 3 4 5 6 8 9 1210 11 13 1914 15 16 17 18 20 21 2422 23 25 3126 27 28 29 30 32
Reserved = 0Frame Count (FC)
Sequence Indicator (SQ)
Time for transmitting ONE multi-frame:Length of MF x Frame Repetition Rate32 bit x 500µs = 16ms
Low Order VC Frame Counter:FC x Length of Multi-Frame x Frame Repetition Rate
FC - Multi Frame Indicator5 bits - Counter incremented with each 32 bit multi-frameCounts from 0 to 31
Low Order VC - K4 byte
Page 46
FC x Length of Multi-Frame x Frame Repetition RateMax. tolerable Differential Delay = 32 x 32 x 500µs = 512ms
SQ - Sequence Indicator6 bits - Transmitted once every 32 bit multi-frameMax. number of Low Order VCG members = 64
Virtual Concatenation - Benefits
VC
EconomicalRe-use core network equipment � invest only at the edge
Efficient & Scalable
Fine granularity & multi-path capability
Page 47
VCBENEFITS
Well-knownSONET/SDH is well
engineered & reliable & trained
Low Investmentdeployment only on customer demand� Fast ROI
Challenges ahead...� How can path bandwidth be increased or decreased?
� � Dynamic Bandwidth Provisioning� “..bring an additional truck on the road..”
VC-3 #1VC-3 #2
VC-3 #?
Page 48
VC-4 #1VC-4 #3
FAILED
� How can we ensure QoS for data services? � � VCG - Protection �one VC container fails - the whole
Virtual Concatenation Group (VCG) fails!
LLinkinkCCapacityapacityAAdjustmentdjustmentAAdjustmentdjustmentSSchemecheme
Virtual Concatenated Groups
Answer:The containers do not know it!That’s the job of the network management!
Question:How does a container know that it belongs to a VCG?
Question:Which containers can belong to the same group?
Page 50
Which containers can belong to the same group?
Answer:They must all start at one port!And They must all end at one port!
A
B
A
B
A A
VC-4
Virtual Container IndicatorProblem:How to distinguish between VCG members of one group?
SQ=0
Solution:Give each member an individual “number plate”!� Sequence Indicator (SQ)
Page 51
VC-4
VC-4
VC-4
SQ=1
SQ=2
SQ=3
Result: VCG members can now be distinguished and sorted!
Time Stamp Mechanism
VC-4 SQ=0
Problem:How do we know that members arriving together started together?
Solution:Give each VCG an individual number� Frame Counter (FC)
SQ=0SQ=0 SQ=0SQ=0 SQ=0SQ=0 SQ=0 SQ=0SQ=0SQ=0
Page 52
VC-4
VC-4
VC-4
VC-4
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 1
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 1
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 2
SQ=0
SQ=1
SQ=2
SQ=3
FC = 1
SQ=0
SQ=1
SQ=2
SQ=3
FC = 0
SQ=0
SQ=1
SQ=2
SQ=3
FC = 2
SQ=0
SQ=1
SQ=2
SQ=3
FC = 3
SQ=0
SQ=1
SQ=2
SQ=3
Storage
VCG Realignment
DemappingArrival
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = max
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = 2
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = 2
SQ = 1
SQ = 0FC = 0
SQ = 1
SQ = 0FC = 1
SQ = 1
SQ = 0FC = 2
SQ = 1
SQ = 0FC = 3
SQ=2 is one frame late!
Page 53
SQ = 1FC = max
SQ = 3FC = max
SQ = 1FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 2FC = max
SQ = 3FC = 0
SQ = 1FC = max
SQ = 2FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = max
SQ = 2FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = max
SQ = 2FC = max
SQ = 3FC = max
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = 2
SQ = 2FC = 1
SQ = 3FC = 2
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = 2
SQ = 2FC = 1
SQ = 3FC = 2
SQ = 1FC = 0
SQ = 3FC = 0
SQ = 2FC = 0
SQ = 1FC = 1
SQ = 3FC = 1
SQ = 1FC = 2
SQ = 2FC = 1
SQ = 3FC = 2
SQ = 1FC = 3
SQ = 3FC = 3
SQ = 2FC = 2
Stop
Differential DelayProblem:Every individual container of a VCG might take a different route through the network - Delay?
Propagation Delay (optical fiber):is approximately 5 µs/km � 1000km extra path length = 5ms Differential Delay� Once around the earth Extra (42.000km) = 210ms DD
Page 54
Result: Differential Delay� Different physical path lengths will result in different path delays for individual containers!
� Once around the earth Extra (42.000km) = 210ms DD
Solution:A container storage & realignment process is necessaryto compensate for differential delay!
Los Angeles
Seattle
Dallas
Washington
Chicago
San Francisco
San Jose
Atlanta
New York
Boston
Kansas CityDenver
Columbus
Los Angeles
Seattle
Dallas
Washington
Chicago
San Francisco
San Jose
Atlanta
New York
Boston
Kansas CityDenver
Columbus
Location B
Bandwidth Provisioning - today
Page 55
Houston OrlandoHouston OrlandoLocation A
� 50Mbit/s Ethernet Private Line (VC-3-1v/ STS-1-1v)
� The customer now requires 100Mbit/s
But: Traffic will be interrupted to bring 100M into service!!
� Operator manually sets up a 2nd path� using the network management system� 100M = VC-3-2v / STS-1-2v
LCAS Overview
LinkCapacity
Adjustment
Extension for Virtual Conc.� carried in H4/K4 byte
Add/Remove bandwidth uninterrupted
Page 56
AdjustmentScheme
End-to-endReal-Time
Communication
Standardized ITU-T G.7042, referred by ANSI
HandshakeProtocolbetween edge NE
Los Angeles
Seattle
Dallas
Washington
Chicago
San Francisco
San Jose
Atlanta
New York
Boston
Kansas CityDenver
Columbus
Los Angeles
Seattle
Dallas
Washington
Chicago
San Francisco
San Jose
Atlanta
New York
Boston
Kansas CityDenver
Columbus
LCAS - Add Bandwidth hitless
Location BNE
NE
Page 57
Houston OrlandoHouston Orlando
� Operator manually provisions add. 50M path
Location A
� Operator installs VC & LCAS edge equipment
� LCAS protocol runs between the two edge NE!� NE negotiate - when the additional path gets valid
and into service!
� LCAS Succeeds � A connection with 100M is in service!
VC-4
Virtual Container (VC)
Terms, Terms, Terms
VC-4 #1
VC-4 #2
Start Point Termination Point
Link VCVC
VC
Page 58
VCGVirtual Concatenated
Group
VC-4 #2
VC-4 #3 Member Number 3of VCG ...is a connection through a network
from start of to the termination point for a complete VCG or an individual member of a VCG.
A Link
Control Packets - information packetsexchanged between source & sink.
GGeneralizedeneralizedCControlontrolPPacketacketPPacketacket
VC & LCAS Control Packet
Frame Counter
MFI
VCGSequence Indicator
SQ
LCASError
Protection
CRC
LCASMember Status
MST
LCASControl
Commands
CTRL
LCASSource
Identifier
GID
LCASResequence
Acknow-ledgement
RS-Ack
Page 60
VirtualConcatenation
Information LCAS Information
Information Packets exchanged between the two edge network elements to adjust the bandwidth.
Control Packet - MFICRCMSTMFI SQ CTRL GID RS-Ack
MFI - Multi Frame Indicator Field� it is a frame counter which will be incremented with each frame� All VCG members will have the same counter value� reaching the maximum counter value the counter restarts at “0”
Sink Source
Page 61
MFI is necessary for� realigning virtual concatenated containers of one VCG at the sink� determing the differential delay between members of the same VCG
MFI = 0 MFI = 1 MFI = 2 MFI = max MFI = 0 MFI = 1
Sink Source
Control Packet - SQCRCMSTMFI SQ CTRL GID RS-Ack
SQ - Sequence Indicator Field� each member of a VCG has it own, unique sequence number� the values start at “0” - max. 63 (LO) or 255 (HO)
SQ = 0 SQ = 0 SQ = 0 SQ = 0 SQ = 0
Sink SourceVCG
Page 62
SQ is necessary for� differentiating the members of a virtual concatenated group (VCG)
MFI = 0
SQ = 0
MFI = 0
SQ = 1
MFI = 1 MFI = 2 MFI = 255 MFI = 0
MFI = 1 MFI = 2 MFI = 255 MFI = 0
SQ = 0 SQ = 0 SQ = 0 SQ = 0
SQ = 1 SQ = 1 SQ = 1 SQ = 1
Member 0
Member 1
EOSSink Source
Control Packet - CTRL
CTRL - Control Field for LCAS� is used to transfer information from the source to sink� it contains the LCAS control commands to initiate or terminate the
bandwidth adaptation process
CRCMSTMFI SQ CTRL GID RS-Ack
Page 63
VCG Link
EOS
IDLEADD
NORMSink Source
CTRL - is used to� synchronize source and sink LCAS process� provide LCAS status information about every individual VCG
member
Control Packet - CTRL
LCAS Control words� FIXED (0000) - Non LCAS Mode
� Indication that LCAS mode is not used at the source- fixed bandwidth
CRCMSTMFI SQ CTRL GID RS-Ack
� ADD (0001)- Increase bandwidth of a VCG
Page 64
� ADD (0001)- Increase bandwidth of a VCG� A container, which is currently not a member of the group, but is
“asking” to become an active member of a VCG.
� NORM (0010) - Normal Transmission� This container is an active member of a VCG and currently
transporting client payload
Control Packet - CTRLCRCMSTMFI SQ CTRL GID RS-Ack
� IDLE (0101) - Currently not in use
LCAS Control words� EOS (0011) - End of sequence & Normal Transmission
� This container is the last active member of a VCG and currently transporting client payload.
Page 65
� DNU (1111) - Do Not Use� The payload of this container can’t be used, because the sink
reported FAIL status� But it is still a member of the VCG, but currently “out of service”
� IDLE (0101) - Currently not in use� Pre-provisioned container, but currently not in use or about to be
removed from a group - is not carrying client payload.� At initiation of a new VCG, members should have CTRL=IDLE state
Control Packet - GIDCRCMSTMFI SQ CTRL GID RS-Ack
GID - Group Identification Bit� is a “security” mechanism to ensure that all members are belonging
to the same VCG� every member of a VCG has the same GID bit value� GID content is a PRBS 215-1
Page 66
GID - is used to� verify that all members are coming from the same source� identify all members of a VCG
Member 0
Member 1MFI = 0SQ = 0GID = 0
MFI = 1SQ = 0GID = 0
MFI = 2SQ = 0GID = 1
MFI = 0SQ = 1GID = 0
MFI = 1SQ = 1GID = 0
MFI = 2SQ = 1GID = 1
MFI = 255SQ = 0GID = 0
MFI = 0SQ = 0GID = 1
MFI = 255SQ = 1GID = 0
MFI = 0SQ = 1GID = 1
Control Packet - MSTCRCMSTMFI SQ CTRL GID RS-Ack
MST - Member Status field� reports the status for every member of a VCG from sink to source
(= back channel) with one bit� there are two MST states for each individual VCG member:
� OK = 0 or FAIL = 1
Page 67
Member Status information� is spread across multiple frames .� corresponds directly to a certain VCG member� is always reported for the max. number of VCG members (64 or
256)� should report MST=FAIL on initiation of a new VCG� should switch to MST=OK on reception of ADD, NORM or EOS
Control Packet - MST ExplainedCRCMSTMFI SQ CTRL GID RS-Ack
Example:VC-12-3v MFI = x
SQ = 0MFI = xSQ = 1
MFI = xSQ = 2
MFI = xSQ = 0
MFI = xSQ = 1
MFI = xSQ = 2
Sink to Source Communication
Source to Sink
Page 68Control Packet 8 MST = FAIL for SQ=63
Control Packet 0 MST = FAIL for SQ=3
MST = OK for SQ=0Control Packet 0
Control Packet 0 MST = OK for SQ=1
Control Packet 0 MST = OK for SQ=2
Sink to Source Communication
Control Packet - RS -AckCRCMSTMFI SQ CTRL GID RS-Ack
RS-Ack - Re-sequence Acknowledge bit� If any sequence number changes are detected at the sink the RS-
Ack Bit is toggled (from “0” to “1 or from “1” to “0”)� BUT only after the status for ALL members have been evaluated� An RS-Ack toggle will be an indication for the source that the sink
has accepted the new member status.
Page 69
has accepted the new member status.
VC & LCAS Control Packet
CRCMSTMFI SQ CTRL GID RS-Ack
CRC - Cyclic Redundany Check� the content of a control packet is protected by a CRC� if errors are detected the control packet is rejected
Page 70
LLCAS CAS summarysummarysummarysummary
Control Packet OverviewInformation Direction
Source � Sink
MFIMulti-Frame Indicator is an counter• to distinguish several VCGs* from each other• necessary to compensate for Differential Delay
SQSequence Indicator is an counter• to differentiate individual VC-n containers within a VCG*• to re-sequence VC-n containers at the termination point in case that differential delay occured
Page 72
case that differential delay occured
CTRLLCAS Control Words are• the actual commands which will show the status of containers from a VCG* initiate bandwidth changes• FIXED - container in NON-LCAS mode• ADD - container which will be added to a VCG• REMOVE - container which will be removed from a VCG• NORM - container as part of an active VCG• EOS - last container of an active VCG• DNU - container with failures(“do not use”)
*VCG = Virtual Concatenated Group
Control Packet OverviewInformation Direction
Source � Sink
GIDGroup Identification Bit is• an additional verification mechanism to secure that all incoming VCG members belong to one group
RS-AckRe-sequence acknowledgement is• an mechanism, where the sink reports to the source the detection of any additions/removals to/from the VCG
Page 73
CRCCyclic Redundancy Check is a• protection mechanism to detect bit errors in the Control Packet
MSTMember Status Field is• an mechanism, where the sink reports to the source which VCG members are currently and correctly received
detection of any additions/removals to/from the VCG
*VCG = Virtual Concatenated Group
CControlontrolPPacketacketTTransportransportTTransportransportHHigh & igh & LLow Orderow Order
Where are the LCAS bytes?
V5J1VC-3 / VC-4
• LCAS info aligned with VC info• Carried in one bit in K4-Byte
• 32 frame Multi-Frame
High Order LCAS Low Order LCAS• LCAS info aligned with VC info• Information also in H4 Byte• 16 frame Multi-Frame
Page 75
J2N2K4
V5VC-2 / VC-11/VC-12
out ofVC-2-Xv / VC-11-Xv /VC-12-Xv
F2H4F3K3
B3C2G1
J1
N1
VC-3 / VC-4out of
VC-3-nv / VC-4-nV
*CP = Control Packet
Low Order Control Packet
J2N2K4
V5VC-2 / VC-11/VC-12
out ofVC-2-Xv / VC-11-Xv /VC-12-Xv
Low Order VC & LCASHow to build a multi-frame control packet?• Filter from each K4 byte only bit no. 2• Store bit no. 2• After 32 VCs, one complete VC & LCAS • control packet was received.
K4
b2Filter
32x K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
K4
b2
Page 76
CRC-3Member StatusSequence
Indicator CTRLGID
Spare
RS-ACK
Frame Count
1
b2Filter
2
b2
3
b2
4
b2
5
b2
6
b2
7
b2
8
b2
9
b2
11
b2
12
b2
13
b2
14
b2
15
b2
16
b2
10
b2
17
b2
18
b2
19
b2
20
b2
21
b2
22
b2
23
b2
24
b2
25
b2
27
b2
28
b2
29
b2
30
b2
31
b2
32
b2
26
b2
Virtual ConcatenationInformation
LCAS Information
GID - Group Identification Bit1 bit - per 32 bit multi-frame � Content is a PRBS 215-1Receiver does not have to synchronize to PRBS
CTRL - LCAS Control Words4 bits - with six possible control words currently definedOne control word is transmitted per 32 bit multi-frame
Low Order LCAS - K4 byte
Page 77
MST - Member status field8 bits - Status of 8 VCG members is reported per control packetReport time for all 63 member statuses: 128ms128 ms = 8 packets x 16ms control packet time
RS- Ack - Re-Sequence Acknowledgement1 bit - Transmitted once every 32 bit control packet
CRC - Cyclic Redundancy Check3 bits - to detect errors in a control packet
High Order LCAS - H4 byte
0123456
MFI1 MFI2
H4 Byte Multi-FrameBit 1 - 4 Bit 5 - 8
MFI1 (bit 1-4)
0 0000 1000 0100 1100 0010 1010 011
MFI2 (bit 1-4)MFI2 (bit 5-8)
8 bit
Reserved “0000”Reserved “0000”
CRC-8
GID “000x”1 bitCTRL4 bit
Page 78
6789
101112131415
n
0 0110 1111 0001 1001 0101 1101 0011 1011 0111 111
SQ (bit 1-4)SQ (bit 5-8)
8 bit
Time for transmitting ONE multi-frame: 16 byte x 125µs = 2ms
Reserved “0000”Reserved “0000”Reserved “0000”
CRC-8CRC-88 bit
Member Status (MST)Member Status (MST)
8 bit
RS-Ack “000x”1 bit
GID - Group Identification Bit1 bit - per multi-frame � Content is a PRBS 215-1Receiver does not have to synchronize to PRBS
CTRL - LCAS Control Words4 bits - with six possible control words currently definedOne control word is transmitted per multi-frame (16x H4)
High Order LCAS - H4 byte
RS- Ack - Re-Sequence Acknowledgement
Page 79
RS- Ack - Re-Sequence Acknowledgement1 bit - Transmitted once every multi-frame
MST - Member status field8 bits - Status of 8 VCG members is reported per multi-frameReport time for all 256 member statuses: 64ms64 ms = 256/8 x 2ms control packet time
CRC - Cyclic Redundancy Check8 bits - to detect errors in a control packet
AAnnEExamplexample
To change the bandwidth on a link it is necessary to� Send information from Source to Sink
LCAS communication is uni-directional , every VCG link must be set-up and commissioned separately,
BUT LCAS needs always a back channel! (Sink to Source)
One uni-directional VCG connection from source to sink
Commands & Directions
� Send replies from Sink to Source
Page 81
Source to Sink Communication
MFISQCTRLGIDCRC
Source Sink
Sink to Source Communication
MST RS-Ack
Example LCAS Handshake� Bi-directional connection between network element (NE) 1 & 2
� Each H-4 byte in each VC-4 container carries every 16 frames (= multi-frame) one control packet which contains the VC and LCAS information for these links
� VCG B consists of p VC-4 containers, e.g. p = 1 � VC-4-1
� VCG A consists of n VC-4 containers, e.g. n = 2 � VC-4-2v
Page 82
Link of VCG B
Link of VCG ANE 1 NE 2
VC-4-1vVC-4 #0
VC-4-2v
VC-4 #1VC-4 #0
Control Packets in H4
Information sent incontrol packet x
of container nin VCG A
Information Flow Chart
Information for status ofcontainer n of VCG A
MFI_A
SQ(n)
CTRL(n)
CRC_x
GID_AMST_B(n)
RS-Ack_B
Link of VCG ANE 1 NE 2
Page 83
Information sent incontrol packet y
of container pin VCG B
Information for status ofcontainer p of VCG B
MST_A(n)
RS-Ack_A
MFI_B
SQ(p)
CTRL(p)
CRC_y
GID_B
Link of VCG B
LCAS Protocol - is uni-directional� links in forward and backward direction are directional
independent� Changes in one direction (link) do not imply any changes in
the other direction (link)� But LCAS assumes that there is always at least ONE
container in the backward direction!
Backward Channel
Page 84
container in the backward direction!
Result� Therefore all member status information and RS-
acknowledgment bits are always multiplexed into only ONE container!
SStandardtandardLLinkink
What’s the status of Link A?� Counter from 0 to max, increased with every VCG send by NE 1 MFI
SQ� VC-4 No. 0 � SQ=0 � First container in VCG A� VC-4 No. 1 � SQ=1 � Second container in VCG
CTRL� VC-4 No. 0 � CTRL=NORM � Normal Transmission and container
No. 0 is part of VCG A� VC-4 No. 1 � CTRL=EoS � Last container in VCG A
� VC-4 No. 255 � Not part of any group! (Network Management)
Page 86
Link of VCG ANE 1 NE 2VC-4-2v
Link of VCG B VC-4-1v
Add. One VC-4 currently not in use!
� VC-4 No. 255 � CTRL=IDLE � Not equipped!
MST � Reports that on VCG A two members with SQ=0&1 are received!
RS-Ack � Nothing to report, as long as there are no member status changes!
AAdding dding BBandwidthandwidth
Adding a new member
• Container No. 0 & No. 1 build an VC-4-2v VCG• A third container is provisioned (end to end), but currently not in use!
1
Back-channel
VC-4 #1
VC-4#0
VC-4-2v
VC-4
Not in use!
Status:
Page 88
• Containers, which are not in use should have the highest possible sequence indicator value (SQ=max).
SQ=255
CTRL=IDLE
MST 0 & 1 = OK2 to max = FAIL
RS-Ack = 0
SQ
CTRL
SQ=0
CTRL=NORM
SQ=1
CTRL=EoS
Status:
Adding a new memberVC-4
#1VC-4
#0VC-4
The network management system sends a request for additional bandwidth to the NE 1 and wants to assig n
unequipped container.2
SQ SQ=0 SQ=1 SQ=2
Back-channel
MST 0 & 1 = OK2 to max = FAIL
Page 89
CTRL CTRL=NORM
CTRL=EoS
CTRL=ADD
� next higher SQ value is assigned to the unequipped VC-4 � In the control word an “ADD” request is send to NE 2
2 to max = FAIL
RS-Ack = 0
Adding a new member
After a certain time (propagation delay) NE 2 will detect a new, correct container (SQ=2) with CTRL=ADD
3
VC-4 #1
VC-4#0
VC-4#2
Back-channel
� NE 2 waits for the next opportunity to report this new member to NE 1 (once every 32 multi-frames with 16 frames each)
4
Page 90
MST 0/ 1/ 2= OK3 to max = FAIL
RS-Ack = 0
SQ
CTRL
SQ=0
CTRL=NORM
SQ=1 SQ=2
CTRL=EoS
CTRL=ADD
frames each)
� NE 2 will send a member status = OK message for container No. 2 to NE 1� MST (0, 1, 2) = OK, MST (all others) = fail
5
Adding a new member
NE 1 will save this new member status in a temporar y register, but does not make any changes to the VCG!
6
VC-4 #1
VC-4#0
VC-4#2
Back-channel
NE 2 will toggle the RS-Ack Bit with the next start of a multi-frame to indicate NE 1 that this new configuration can now go alive
7
Page 91
alive
SQ
CTRL
SQ=0
CTRL=NORM
SQ=1 SQ=2
CTRL=EoS
CTRL=ADD RS-Ack = 1
MST 0/ 1/ 2= OK3 to max = FAIL
Adding a new member
After receiving the toggled RS-Ack bit NE 1 will � take the new member status from the temporary register as the new, valid one.� change the CTRL words for container 1 & 2!
8
VC-4 #1
VC-4#0
VC-4#2
Back-channel
Page 92
SQ
CTRL
SQ=0
CTRL=NORM
SQ=1 SQ=2
CTRL=NORM
CTRL=EOS
RS-Ack = 1
MST 0/ 1/ 2= OK3 to max = FAIL
Adding a new member
After changing the Control Word of an SQ=2 containe r to “End of Sequence” NE 1 will map valid payload into THE NEXT VC-4 container!
9
VC-4 #1
VC-4#0
VC-4#2
Back-channel
The new VC -4-3v group is now active and NE 2 will demap the payload correctly!
10
Page 93
SQ
CTRL
SQ=0
CTRL=NORM
RS-Ack = 1
SQ=1 SQ=2
CTRL=NORM
CTRL=EOS
MST 0/ 1/ 2= OK3 to max = FAIL
The new VC -4-3v group is now active and NE 2 will demap the payload correctly!
10
“ADD” ExplainedRequest from NMS to increase bandwidth on a existing link.1Source
Actions for the currently unequipped container :a) assign a valid sequence indicator (SQ=currently highest +1)b) change CTRL=ADD (from CTRL=IDLE)
2Source
Sink replies with MST=OK after detection of the new member3Sink
Sink acknowledges the new status with the beginning of the next multi-frame (RS-Ack toggles )4Sink
Page 94
multi-frame (RS-Ack toggles )4Sink
With reception of acknowledgement source will changea) the status of the last member from CTRL=EoS to NORMb) the status of the new member from CTRL=IDLE to EoS
5Source
After the reception of the new member with CTRL=EoS Sink will start the demapping process with the next container !7Sink
Source starts to map payload information in the next upcoming container6Source
SStatetateDDiagrammiagramm
LCAS - ITU-T State Diagram
NMS LCAS Sk Sk Sk
CTRL=ADD
CTRL=ADD
MST=OK
mema(new) mema +1(new)memn-1(EOS)Note 1
Note 2
Note 3
Note 4
Add cmnd
connectivitycheck
connectivitycheck
Page 96
CTRL=NORM CTRL=EOS
CTRL=NORM CTRL=EOS
MST=OK
Note 5
Note 6
Note 7
LLinkinkFFailureailure
Sink detects an failure of one member� Sink changes the member status of this member to FAIL� On detection of this new member status Source will set
CTRL from NORM or EoS to DNU (Do not use) � Sink does not demap the payload anymore.
Temporary Failure
Sink detects the clearance of the failure status
Page 98
Sink detects the clearance of the failure status� Sink sets the member status of this member to OK� On detection of this new member status Source will set
CTRL to NORM or EOS again� Sink will now demap th
Auto Recovery of VC links possible
Link Capacity Adjustment Scheme
LCAS
Cost EfficientNew NE necessary
only at the edge�Transparent to
core network
Enables Value added services�Bandwidth on demand�”Soft” Protection�99.999% up-time
Page 99
LCASBENEFITS
Flexible & scalableOffers variable VC bandwidth in real-time!
RestorationVirtual Concatenation
link protection & recovery
Challenges ahead� Efficient & suited mappings for all diverse data
clients!� “...one mapping fits all...?!?”
SONET/SDH
Page 100
� Rate adaptation between asynchronous clients and synchronous transport network
Asynchronous Rates
Synchronous Rates
GGenericenericFFrameramePProcedurerocedurePProcedurerocedure
SO
NE
T M
UX
/DE
MU
X
Nat
ive
Inte
rfac
es
New SONET/SDH at the Edge
?VC LCASGFPEthernet
Ficon
Edge CoreAdaptation
Customer Operator
Page 102
SONET/SDH
SO
NE
T M
UX
/DE
MU
X
Nat
ive
Inte
rfac
es ?
That’s “ New SONET/SDH “
VirtualConcatenation
Link Capacity
Adjustment Scheme
Generic Frame
Procedure
LAPS
Ficon
Escon
Fibre Channel
GFP Overview
GenericFrame
Data En-capsulationfor various services
Rate Adaptation Mechanism
Page 103
FrameProcedure
Asynch.clients over synchronous networks
Standardized ITU-T G.7041
referred by ANSI
SANs
FIC
ON
ES
CO
N
Ethernet
DV
I
HDLC
Frame Relay POS
DATA (IP, IPX, MPLS,...)
RPR
Fib
re C
hann
el
Voice Video
PrivateLines
The Big picture
Page 104
ATM
HDLC
Fiber
GFP-T
SONET/SDH
WDM / OTN
GFP-FGFP
GFP - Layer Model
GFP - Client Specific Aspects (payload dependent)
GFP - Common Aspects
Ethernet IP/PPP Fibre Channel OthersClients
GFPFrame Mapped Transparent Mapped
ESCON
Page 105
GFP - Common Aspects (payload independent)
SONET/SDH VC-n Path
OTN ODUk Path
Others(e.g. Fibre)
Transport
Generic Frame Procedure� G.7041 Generic Frame Procedure defines
� Client encapsulation - for transport over
SONET/SDH or OTN networks
� Frame formats - for various clients
� Mapping Procedures - for client signals into
Page 106
GFP
� Why do we need a new framing procedure?
� simple and scalable traffic adaptation for different
transport rates
� flexible approach for data transmission which
requires stringent delay, QoS
SStructure tructure ooffGGFP FP -- FFramesramesGGFP FP -- FFramesrames
Core Header
GFP Frame Overview
Client Payload Field
Payload Headers gives type of client and supports client specific management procedures � Includes CRC detection & correction � Length 4 to 64 byte
PayloadHeaders
Core Header contains the length of the payload area � and start of frame info� and CRC-16 error detection & correction� Length 4 byte
Page 108
PayloadArea
8 bit
GFP Payload Area transports higher layer specific information� Length 4 to 65535 byte
Client Payload Field contains �client frames (GFP-F) or�client characters (GFP-T)
ClientPayload
Information
Optional Payload FCS protects the client payload information field� CRC-32 Length 4 byte
OptionalPayload FCS
GFP gets scrambled before transmission!
GFP - Common Aspects
Core Header
PLIPLI
cHECcHEC
PayloadHeaders
4 byte
X=4-64 byte
4 byte
Page 109
PayloadArea
8 bit
ClientPayload
Information
OptionalPayload FCS
4 to 65535 byte
8 bit
0 to 65535-X byte
4 byte
GFP - Core Header
Core Header
PLI - PDU Length Indicator� 16-bit field contains a binary number,
representing the length of the payload area :� min.: 4 byte (PLI = 00 04hex)� max.: 65535 byte (PLI = FF FFhex)� PLI = 0hex to 3 hex reserved for
control frames
PLIPLI
cHECcHEC
1
1
11
1 2 3 4 5 6 7 8
Page 110
PayloadArea
cHEC - Core Header Error Control� contains a CRC-16 error control code to protect the integrity
of the core header. � It enables
� to correct a single bit error� to detect multiple bit errors
GFP -Control Frames
�GFP IDLE FramesIDLE Frame
� GFP Control Frames are used in the managment of the GFP connection.
� Four Control Frames are available � PLI= 00 00hex to PLI = 00 03hex
� BUT only one Control frame is currently specified:
Page 111
�GFP IDLE Frames� The smallest, possible GFP frame with
only 4 byte long� PLI = 00 00hex
� IDLE frames are necessary� for rate adaptation process� robustness of the frame
synchronization process
IDLE Frame
PLI =00PLI= 00
cHEC = 00cHEC = 00
GFP Frame HierachyGFP Frames
Client Frames
PLI ≥≥≥≥ 04hex
Control Frames
PLI ≤≤≤≤ 03hex
Page 112
GFP - Payload Header
Payload Type Field� is mandatory for GFP client frames (PLI ≥4)
� Provides information about� content & format of the Client Payload
Information� indicates different GFP frame typesPayload
Core Header
Client
PayloadHeaders
Payload Type
Extension
Page 113
� indicates different GFP frame types� distinguishes between different services
in a multi-service environment
PayloadAreaClient
PayloadInformation
OptionalPayload FCS
ExtensionHeaderField
GFP - Payload HeaderPTI - Payload Type Identifier� 3-bit field, which indicates the type of
GFP client frameCurrently defined� PTI = 000 �Client Data� PTI = 100 �Client Management� PTI = Others � Reserved
PFI - Payload FCS Indicator
PayloadType
ExtensionHeaderField
PTI PFI EXIUPI
tHECtHEC
1
1
11
1 2 3 4 5 6 7 8
Page 114
PFI - Payload FCS Indicator� 1-bit field indicates the � PFI = 1 � Presence� PFI = 0 � Absence� of the optional payload Frame Check Sequence (pFCS) field
EXI - Extension Header Identifier� 4-bit field indicates the format of the Extension Header FieldCurrently defined� EXI = 0000 � Null Extension Header� EXI = 0001 � Linear Frame� EXI = 0010 � Ring Frame� EXI = Others � Reserved
Field
GFP - Payload HeaderUPI - User Payload Identifier� 8-bit field identifies the type of client/service
encapsulated in the GFP Client Payload Field
� Interpretation of UPI values is different for � Client data frames (PTI=000) or � Client management frames (PTI=100)
� More details on the next slides
PayloadType
ExtensionHeaderField
PTI PFI EXIUPI
tHECtHEC
1
1
11
1 2 3 4 5 6 7 8
Page 115
tHEC - Type Header Error Control� 16-bit error control code� to correct one bit error or� to detect multiple bit errors in the payload type field
Field
GFP Frame HierachyGFP Frames
Client Frames
PLI ≥≥≥≥ 04hex
PTI = 000bin PTI = 100bin PLI = 00hex PLI = 01 to 03hex
Control Frames
PLI ≤≤≤≤ 03hex
Page 116
Client DataFrames
Client Management
Frames
IdleFrames
Other Frames (for further study)
Currently defined Client Data Frames - User Payload Identifier(UPI)� UPI = 00 & FF � Reserved and not available
GFP - Client Data Frames
PTI PFI EXIUPI
tHECtHEC Indication in the Type field
PTI = 000
Clients and services are transported over GFP Client Data Frames
Page 117
� UPI = 00 & FF � Reserved and not available� UPI = 01hex � Ethernet (frame-mapped)� UPI = 02hex � PPP (frame-mapped)� UPI = 03hex � Fibre Channel (transparent-mapped)� UPI = 04hex � FICON (transparent-mapped)� UPI = 05hex � ESCON (transparent-mapped)� UPI = 06hex � Gigabit Ethernet (transparent-mapped)� UPI = 07hex � Reserved for future use� UPI = 08hex � Multiple-Access Protocol over SDH (frame-mapped)� UPI = 09 to EF � Reserved for future use� UPI = F0 to FE � Reserved for proprietary use
GFP - Client Management Frames
Currently defined Management Frames
PTI PFI EXIUPI
tHECtHEC
Indication in the Type fieldPTI = 100
This functionality provides a mechanism to send management information from the GFP source to the GFP sink
Page 118
Currently defined Management Frames� UPI = 00 & FFhex � Reserved and not available� UPI = 01hex � Loss of Client Signal (Client Signal Fail)� UPI = 02hex � Loss of Character Synchronization� UPI = 03 to FEhex� For future use
GFP Frame HierachyGFP Frames
Client Frames
PLI ≥≥≥≥ 04hex
PTI = 000bin PTI = 100bin PLI = 00hex PLI = 01 to 03hex
Control Frames
PLI ≤≤≤≤ 03hex
Page 119
Client DataFrames
Client Management
Frames
IdleFrames
Other Frames (for further study)
Dependent onClient
UPI =00hex to FFhex UPI = 01hex UPI = 02hex
Loss of ClientSignal
Loss of ClientSynchronization
UPI = 00hex or FFhex
Reserved
GFP - Extension Header
Extension Header Field� supports technology specific data link
headers, e.g.� virtual link identifier� source/destination adress� Class of Service
� it is 0-60 byte long and indicated in the Type field (EXI)Payload
Core Header
Client
PayloadHeaders
Payload Type
Extension
Page 120
field (EXI)� Three Extension Header Variants are
currently defined for point-to-point or ring configurations
� EXI = 0000 � Null Extension Header� EXI = 0001 � Linear Frame� EXI = 0010 � Ring Frame� EXI = Others � Reserved
PayloadAreaClient
PayloadInformation
OptionalPayload FCS
ExtensionHeaderField
GFP - Null Extension HeaderNull Extension Header (EXI = 0000 (0hex))� applies to logical point-to-point configuration, where
the transport path is dedicated to one client or service onlytHEC
tHEC
TypeType
1
1
1
1
1 2 3 4 5 6 7 8
Page 121
� the extension header field itself is not presentExtensionHeaderField
GFP - Linear Extension Header
CID - Channel ID� 8-bit field to indentify up to 256 independent GFP
channels over the same linkCIDSpare
1
1
tHECtHEC
TypeType
1
1
11
Linear Frame Extension Header (EXI = 0001)� applies to linear (point-to-point) configurations,
where several independent clients or services are aggregated to one transport path
Page 122
Extension HeaderField
eHEC - Extension Header Correction� 16-bit error control code� to correct on bit error� to to detect multiple bit errors in the extension
header field
eHECeHEC
Spare 1
11
Spare� 8-bit field for future use
Extension Header for ring frame � for further study
GFP - Client Payload Area
CPI - Client Payload Information Field� variable length field, which contains the client or service
� GFP-F (frame mapped)� CPI field carries the client frames
� GFP-T (transparent mapped)� CPI field carries (unframed) client charactersPayload
Core Header
ClientPayload
PayloadHeaders
Page 123
� CPI field carries (unframed) client characters� max. length: 65535 byte - payload header - pFCS� More payload spefics on the next slides!
PayloadArea
ClientPayload
Information(CPI)
OptionalPayload FCS
pFCS - Payload Frame Check Sequence� Optional 32-bit control code to protect the client payload
information field� It is present if PFI=1 in the Type field (Payload
Header)� pFCS can only detect bit errors
PTI PFI EXIUPI
tHECtHEC
GFP - Frames Overview
Core Header
PLIPLI
cHECcHEC
PayloadHeaders
PayloadType
4
Page 124
CIDSpare
eHECeHEC
PayloadArea
8 bit
ClientPayload
Information
OptionalPayload FCS
ExtensionHeaderField4 - 65535
GGFP FP --OOperationperationMModesodesMModesodes
GFP Operation Modes
GFP-T (Transparent Mapped):� Client characters are directly mapped in GFP-T
00
GFP-F (Framed Mapped):� For packet oriented clients, e.g. Ethernet� One Client Packet = packed in one GFP frame (1:1)� Minimal overhead
Page 126
GFP IDLE Frame:� Rate Adaptation (“stuffing”)
GFP Management Frame:� under study
� Client characters are directly mapped in GFP-T frames e.g. Fibre Channel� Fixed length GFP frames� Minimal Latency
GFP Operation Modes
1GigE
GFP-F
Frame by Frame
GFPEthernet FrameGFP GFP GFP EthGFPGFPEth. Frame
variable
Page 127
GFP-T
1GigE IDLELE EthEth. Frame IDLEEthernet Frame
TransparentGFP TransparentGFP TransparentGFP GFP
GFP GFP Header or IDLE frames
Block by Block
fixed
GFP
GFP-F Client vs. Transport Rate
Variable Client Rate
GFP-F
Mbit/s
F
I
F
O
IDLEs
+
Mappe
Constant Transport Rate
Mbit/s
Page 128
t O
GFP-F Mapper
+er t
GFP-F IDLEs
Client
EthernetFast EthernetGigabit EthernetIPPPP
GFP-T Client vs. Transport Rate
Mapp
Decoder/ Coder
100+x %
GFP-T
Mbit/s
Constant Client Data Rate
100 %
Mbit/s
Constant Transport Rate
Page 129
GFP-T Mapper
per
/ Coder
t
Effective Payload
Client IDLEs
Fibre ChannelESCONFICONGigabit Ethernet10 GigEAnything!
t
GFP Overhead
Effective Payload
Client IDLEs
GGFP FP --FFramingramingPProceduresroceduresPProceduresrocedures
GFP Procedures
GFP supports six basic procedures:
1. Frame delineation
2. Client multiplexing
3. Frame multiplexing
4. Header Scrambling
Page 131
4. Header Scrambling
5. Payload Scrambling
6. Client Management
GFP - Frame Level Processes
FrameMUX
GFP IDLE
GFP ClientManagement
Byte streams with GFP Data Frames
with client-specific payloadPayload
Scrambler
Core HeaderScrambler
Byte Stream toTransport Payload
Page 132
FrameDEMUX
GFP IDLEFrames Insertion
Transport Payload
GFP IDLEFrames Termination
GFP ClientManagement
GFP Data Frames to client Byte streams
PayloadDescrambler
Core Headercheck
Byte Stream fromTransport Payload
GFP - Frame Delineation
PLI
PayloadGFP
Variable length 4 to 65539 Byte
..... it’s all about synchronisation!
Page 133
GFP uses•the Payload Length Indicator and•the Core Header protection field for frame synchronization
PLI
PLI
cHEC
cHEC
CRC-16
Payload Length Indicator
GFP - Frame Delineation
110100010010111110100100011010010101001111110010010100101001000101111010010101001010101010010111101
PLI cHECComparer
2 byte 2 byte
CRC-16Expected next Core Header
Page 134
CRC-16
1. HUNT State• Searching for a correct formated 4 byte Core Header• Byte by Byte search• Bit Error Correction = disabled
2. PreSync State• Jump to the next correct Core Header using PLI info • Frame by frame search for x consecutive correct cHECs• Bit Error Correction = disabled• Successful? - Yes3. Sync State
• Jump to the next frame using PLI• Single Bit Error Correction = enabled• Detection of Multiple Bit Errors?
PreSync
PreSync
Frame-by-Frame
GFP - Frame Delineation Diagram
nextcHEC
incorrect
PreSync
PreSync
Frame-by-Frame
X ≥≥≥≥ 1consecutive
correctcHECs
Page 135
IDLE frames participate in the synchronization proc ess!
HUNT
correctcHEC
detected
Multiple-Bit Errors detected
(Incorrect HEC)
correctcHEC
detected
SyncFrame
-by-Frame
Byte-by-Byte
PreSync
PreSync
Frame-by-Frame
GFP - Frame Delineation Diagram
nextcHEC
incorrect
PreSync
PreSync
Frame-by-Frame
X ≥≥≥≥ 1consecutive
correctcHECs
Page 136
IDLE frames participate in the synchronization proc ess!
HUNT
correctcHEC
detected
Multiple-Bit Errors detected
(Incorrect HEC)
correctcHEC
detected
SyncFrame
-by-Frame
Byte-by-Byte
GFP - Frame & Client Multiplexing
GFP Signals from multiple ports or clients are mult iplexed on a frame by frame basis• GFP IDLE cells are transmitted in case of no other clients
• GFP - a mapper build inside
eHECeHEC
CIDSpare
1..256 signals
GFP Streamswith different clients
Page 137
eHEC
Linear Extension Header
GFPMux
with different clients
IDLE Insertion
CID=0CID=2 CID=1CID=1
CID=0 CID=0CID=0
CID=1CID=1 CID=1
CID=2 CID=2CID=2
GFP - ScramblingCore Header Scrambling
Reason:• Provides sufficient 0��1 transitions• Improves frame delineation process
XOR Scrambler
00 00 00 00 Core Header
Scrambler CodeB6 AB 31 E0
+B6 AB 31 E0
IDLE Frame on transmission
Page 138
• Improves frame delineation process
Reason:• Security against payload information replicating the scrambling word from frame synchronous scramblers in SONET/SDH or OTN
B6 AB 31 E0
Payload Scrambling
ClientPayload
Information
PayloadHeaders
OptionalPayload FCS
X43+1 Scrambler
D1
+D43
Scrambler is only enabled in SYNC STATE!
GFP - Client ManagementA GFP source to GFP sink Client Signal Failure (CSF ) indication process is implemented:• CSF Detection is client specific!
GFP Source GFP SinkTransmission
Detection of Client failureat ingress?
no
Page 139
CSF Frames:UPI=01 Loss of Client Signal or UPI=02 Loss of Client Sync.
Declares Sink Client Signal failure
Valid GFP Frame Received?
No CSF for Nx 1000ms?
Sends Client Mgmt. Frame (PTI=100) every 100-1000ms
CSFyes
at ingress?
Clear Failure Statusyes
no
Send IDLE Frames onlyIDLE
Defect Handling
GFP Common Process
GFP Client Specific(= Source Adaptation Process)
Ingress Client Process (= Client Access Point)
GFP Common Process
GFP Client Specific(= Source Adaptation Process)
Ingress Client Process (= Client Access Point)
X
X
CSF
X
SSF
Page 140
Transport Network
GFP Common Process(= Client Source Adaptation)
Transport Network
GFP Common Process(= Client Source Adaptation)
Physical Connection
X Point of Failure Detection
Failure Indication
Indicators:CSF = Client Signal FailSSF = Server Signal FailureTSF = Trail Signal Fail
X
X
TSF
GGFP FP -- FFPPayloadayloadSSpecificspecificsSSpecificspecifics
Ethernet MAC Payload
7+1 Byte
Preamble
4 Byte
CRC
Payload(und ggf. Padding )
6 Byte
SourceAddress
6 ByteDest.Address
2 Byte
Type /Length
6 Byte
SourceAddress
6 ByteDest.Address
7+1 Byte
Preamble
4 Byte
CRC
Payload(und ggf. Padding)
2 Byte
Type /Length
46 ... 1500 Byte
2 Byte
Type =
8100
2 Byte
Prio, /VLAN
Page 142
802.2 LLC
1Byte
DSAP
1Byte
SSAP
1Byte
CTRL
Payload(und ggf. Padding)
802.2 SNAP
3 Byte
OUI
2 Byte
PrID
Payload(und ggf. Padding)
8 7 6 5 4 3 2 1 0
1 0 0 10 0 0 0 0
0 0 0 00 0 0 0 0
VLAN IDENTIFIER
User Priority CFI
AA AA 03
000000 0800 IP Payload(und ggf. Padding)
GFP & Ethernet MAC Payload
Source AddressDestination Address
PreambleStart of Frame Delimeter
Bytes
7166
tHECType
PLIcHEC
GFP Extension Header
22220-60
Bytes
Source AddressDestination Address
Page 143
Source AddressLength/Type
MAC Client
Pad
Frame Check Sequence
26
4
46-1500
GFP Payload
AsClient
Ethernet MAC Frame GFP-F Frame
Source AddressLength/Type
MAC Client
Pad
Frame Check Sequence
GFP & Ethernet MAC Payload
tHECType
PLIcHEC
GFP Extension Header
Source AddressDestination Address
Length/Type
Eth
erne
tG
FP
Hea
der
� Ethernet Inter-Packet-Gaüs are deleted before encapsulation and restored after transmission
� Byte alignment and bit identification is maintained
Page 144
GFP PayloadMAC Client
Pad
FCS
Eth
erne
t
Ethernet to GFP -FramedUp to 10M
Ethernet Stream
5M7.5M
10M
t1 2 3 4
2.5M
Pure Ethernet
GFP Packet Payload
Core Header
Page 145
Pure Ethernet
Constant Stream
Result
GFP-F Packet GFP-IDLE Packet
00hex00hex00hex00hex
Payload
cHECPLI 2
2
X
Scrambling!
GFP-Framed to VC
GFP-Framed Packet Stream
5M7.5M
10M
t1 2 3 4
2.5M
GFP Stream
Byte-Interleaving
Page 146
GFP Stream
VC-12 #5
VC-12 #4
VC-12 #3
VC-12 #2
VC-12 #1
GFP Framesin VC containers
Transport Thru the Network
Transport
IP & PPP Payload
Flag
ControlAddress
Bytes
111
tHECType
PLIcHEC
GFP Extension Header
22220-60
Bytes
ControlAddress
Page 147
ControlPPP Type
PPP Information
Pad
Frame Check Sequence
21
4
GFP Payload
AsClient
PPP/HDLC Frame GFP-F Frame
ControlPPP Type
PPP Information
Pad
Frame Check Sequence
PPP Payload
PPP Protocol
Bytes
1-21
tHECType
PLIcHEC
GFP Extension Header
22220-60
Bytes
PPP Protocol
Page 148
PPP Information
PPP Padding (optional)
Frame Check Sequence
21
4
GFP Payload
AsClient
PPP/HDLC Frame GFP-F Frame
PPP Information
PPP Padding (optional)
Frame Check Sequence
Ethernet to GFP -F Scheme
Ethernet Control Character Termination,
e.g.
MAC Frame Extraction
Ethernet Switch or Bridge
MAC to GFP-F Encapsulation
ControlTermination
Page 149
GFP-F stream mapped to VC container
VC-n orVC-n-Xv
EthernetFast EthernetGigEthernet
10Gig Ethernet
PHY-x
Ethernet Decode/Clock Recovery
Error Handling
� GFP Source process detects client errors before transmission� Client packets should be discarded by the GFP process� No transmission of errored packets
� GFP Source process detects client errors while in transmission
Page 150
� GFP Source process detects client errors while in transmission� Padded up with all ones bit sequences� Complement all payload FCS (if present) and transmit� Result: GFP Sink process will discard errored packets� Or Client Process will discard errored packets
Generic Frame Procedure
GFP
Reliable�Easy & stabile algorithm�Header Correction
Expandable with no need for
new transport equipment
Page 151
GFPBENEFITS
New Opportunities
Technological & Economical
Compatibleworks with basically any higher layer service and lower layer network!
LLinkinkAAccessccessPProcedurerocedurePProcedurerocedureSSDHDH
And what about LAPS?
LinkAccess
Competitive standard for GFP
Much more limited
capabilitiesthan GFP
Page 153
AccessProcedure
SDH
Only for SDH, Only for CC
Similar to PoS/ HDLC
Standardized ITU-T X.85 & X.86, Asian Initiated Sta ndard.
PProduct &roduct &AApplicationspplicationsAApplicationspplications
Applications in the network� Native Data Services for the customer
� Ethernet Private Lines� Virtual Local Area Networks� Storage Area Networks
� Bandwidth on demand� Manually, Automatically or on schedule
Page 155
� Customized QoS agreements� Premium, Business or Economy Class� Over-subscription
� Multi-Path Traffic Routing
� New Business Models are possible! � See examples at Appendix!
Acterna’s Solution
ONT-50
� New SONET/SDH up to 2.5G� 2.5G SONET/SDH Interfaces� High Order Virtual Concatenation� Basic LCAS Protocol Emulation� GFP Generation� GFP Analyses� Ethernet Frame Generation/Analyses
1st ReleaseApril 2003
Page 156
� Ethernet 1GigE Interfaces� Multi-port Interfaces
� Enhancements on”New SONET/SDH”� New VC, LCAS, GFP functionality
Acterna’s SolutionONT-50
Page 157
Acterna’s SolutionONT-50
Page 158
Acterna’s SolutionONT-50
Page 159
“New SONET” - the evolution of SONET
� Data Services - Ethernet, Fibre Channel & others
� GFP - frames the data & adapts the rates
� VC - offers right sized pipes in fine granularity
� LCAS - makes VC easy & flexible on demand
Result :
Page 160
Ethernet
Ficon
Escon
Fibre Channel
SONET/SDH
MU
X/D
MU
X
Nat
ive
Inte
rfac
es
?GFP
Generic Frame
Procedure
LCAS
Link Capacity
Adjustment Scheme
VC
VirtualConcatination
Result :� SONET/SDH is flexible & data aware!
AApplicationspplications
Eth
erne
t IF
SO
NE
T /
SD
H
Testing Tasks - New SONET/SDH
VC
New Edge Network Element
LCASGFP
! !!Measurement
AccessPoint
Measure. Access
Point
Conversion
Page 162
Eth
erne
t IF
SO
NE
T /
SD
H
! !
No direct measurement access points!!
!Point
• Only end-to-end measurements• Internal Loop Back
Testing Tasks - VC� Multiple Container Handling Tests
� e.g. Overhead, Pointer, etc.
� Test of various bandwidth configurations
STS-1STS-1
STS-1STS-1
VC-4
STS-1STS-1VC-4
RSOH
AU-4 Pointer
MSOH
VC-4-1 VC-4-2
VC-4-5 VC-4-6
VC-4-11 VC-4-12
VC-4-3 VC-4-4
VC-4-7 VC-4-8
VC-4-9 VC-4-10
Page 163
DelayStore
VC-4#2
VC-4#1VC-4
#2
VC-4#1
Re-Assemble
VC-4#2
VC-4#1
Segmentation
� Segmentation and Re-assembly of the payload
� Differential Delay generation and analysis
STS-1VC-4
Re-configureMap
MSOH VC-4-15 VC-4-16VC-4-13 VC-4-14
Testing Tasks - LCAS� Network Transparency Testing
� Testing the Interworking with VC
� Protocol Emulation for up and down stream
� Add and remove VC bandwidth
Page 164
LCAS down stream
LCAS up stream TX
RX
RX
TX
1 72 3 4 5 6 8 9 1210 11 13 191415161718 2021 242223 25 312627282930 32
CRC-3Member StatusFrame
CountSequence Indicator CTRL
GID
SpareRS-ACK
Low Order LCAS Control Frame
Testing Tasks - GFP� Header generation and analysis eg. correctable &
uncorrectable header
� Rate Adaptation Testing to the transport bandwidth
� Generation of GFP management frames
Page 165
� GFP Mapping & Demapping of service payload
SOH
STS Pointer
LOH
STS-1-1 STS-1-2 STS-1-3 STS-1-4
STS-1-5 STS-1-6 STS-1-7 STS-1-8
STS-1-9 STS-1-10 STS-1-11 STS-1-12
STS-1STS-1
STS-1STS-1
VC-4Ethernet
Cor
e H
eade
r
Eth
erne
tP
aylo
ad
Mapping Mapping MappingOverhead (OH) OH OH OH
SONET Virtual Concatenation GFP Ethernet
Bandwidth on demand
Bandwidth “Call-by-Call”
NG NG
Network Management
VC-12-3v
LCAS
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Transport Network
NG NG
ISPCustomer’s LAN
Customer� rents a 6M Internet connection (VC-12-3v)� calls to get additional 2M!Operator� will provision additional VC-12 path� ..and will hitlessadd it to existing connection via LCAS!
+VC-12
LCAS
Bandwidth on demandBandwidth on Schedule
Transport NetworkNG NG
100M 100M
900M900M
100M
900M
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Location A Location B
� Offer a fixed bandwidth schedule:� 24/7 - Virtual Local Area Network service at 100M Ethernet� Every night for one hour -additional 900M ESCON servicefor
data backup
� New revenue opportunities at low traffic hours!
900M900M 900M
Bandwidth on demand
Ethernet Traffic
1st VC-12
2nd VC-12
3rd VC-12
Variable VCG capacity
Automatic Bandwidth Allocation - pay as you grow!
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t1 2 3 4
VCG capacity
Automatic Bandwidth Allocation:� Automatically, pre-provisioned VC capacity will be activated� No paid, but unused link capacity for the customer � Customized SLA possible!
� Optimal bandwidth for the customer for min. $$� New revenues with pay per use & over-subscription!
New Protection Schemes
50 Mbit/s Ethernet
VC-12-8v
VC-12-8v
50 Mbit/s EthernetVC-12-9v
On Failure - 34 M
Regular - 50 M
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� If different VCG members are diversely routed...� LCAS can provide a fault recovery mechanism add. to SONET� Failed VCG members will be removed� A connection at lower speed will remain!� Network Management has time to reroute the link!� Differentiated services on customer side!
�Offers Customized “soft” protection at various service levels!
LCAS Transmitter (TX) with non-LCAS Receiver (RX)� TX will send MFI and SQ according to G.707 or G.709� RX will ignore all other bits of the control packet� The reported member status (RX to TX) will be MST=0 = OK
InterworkingDoes LCAS and non-LCAS virtual concatenation equipm ent
work together?
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Interworking possible
Non- LCAS Transmitter (TX) with LCAS Receiver (RX)� RX expects a CTRL word, which is not “0000” and a correct
CRC field� TX will send CTRL = 0000 and CRC = 0� The LCAS RX shall ignore all information except MFI and SQ
Interworking possible
GFP Technical ApplicationEthernet over SDH/SONET
1GE ADM
H4H4
H4
PLIPLI
cHECcHECTypeTypetHECtHEC
Ethernet Frame GFP Frame VC-4-3v STM-16
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1GE ADM
... ...
tHEC
H4
H4
H4
H4
H4
H4
H4
H4
H4
TThank hank yyou!ou!
StandardsStandardsStandardsStandards
ReferencesITU-TG.707/Y.1322 Network Node Interface for SDH (10/2000)G.709 Network Node Interface for Optical Transport NetworksG.7041/Y.1303 Generic Frame Procedure (12/2001)G.7042/Y.1305 LCAS for Virtually Concatenated Signals
(11/2001)X.85 IP over SDH using LAPSX.86 Ethernet over LAPS
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ANSIT1.105 Synchronous Optical Network
Virtual Conc. LCAS (also refers to ITU-T G.7042)
GFP refers to ITU-T G.7041
IEEEEthernet: 802.3
AbbreviationsAbbreviationsAbbreviationsAbbreviations
AbbreviationsCC: Continguous ConcatenationcHEC: Core Header Error CheckCRC: Cyclic Redundancy CheckEOF: End of FrameEoS: Ethernet over SONETESCON: Enterprise Systems
ConnectionFCS: Frame Check SequenceFD: Full Duplex
MAN: Metropolitan Area NetworkMFI: Multi Frame IndicatorMSOH: Multiplexer Section OverheadNE: Network ElementOTN: Optical transport NetworkOSI: Open System InterconnectPDU: Protocol Data UnitPLI: PDU Length IndicatorPoS: Packet over Sonet
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FD: Full DuplexFICON: Fibre ConnectionGFP: Generic Frame ProcedureGFP-F: Frame mapped GFPGFP-T: Transparent GFPGMPLS: Generalized Mulitprotocol
Label SwitchingIP: Internet ProtocolLAN: Local Area NetworkLAPS: Link Access Procedure SDHLCAS: Link Capacity Adjustment
SchemeMAC: Media Access Control
PoS: Packet over SonetPPP: Point-to-Point ProtocolRSOH: Repeater Section OverheadSAN: Storage Area NetworksSDH: Synchronous Digital HierachyTCP: Transport Control ProtocolTDM: Time Division MultiplexingVC: Virtual ConcatenationVC-xc: Virtual ContainerVCG: Virtual Container GroupWAN: Wide Area Network