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

Page 5

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

Page 9

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

Page 11

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

Page 12

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

Page 13

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

Page 14

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

Page 16

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

Page 17

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

Page 18

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

Page 19

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

Page 20

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)

Page 21

� 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

Page 22

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

Page 23

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

Page 24

VCG Payload Capacity

Maximum

VC-4-2v Payload Size 299,52 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

Page 25


VCG Payload Capacity

Maximum



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

Page 26

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%

Page 27

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

Page 28

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


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 30

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 31

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 32

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 33

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

Page 34

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

Page 37

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

Page 38

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

Page 39

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


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


What’s a multi-frame?

J2N2K4

V5 VC-2 / VC-11/VC-12out of


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

Page 43

6789

101112131415

n


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

Page 44

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


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


� 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 = 255SQ = 0GID = 0


MFI = 255SQ = 1GID = 0


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


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


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


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


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


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


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


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 “


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


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


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


Client Frames


PTI = 000bin PTI = 100bin PLI = 00hex PLI = 01 to 03hex

Control Frames


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


Client Frames


PTI = 000bin PTI = 100bin PLI = 00hex PLI = 01 to 03hex

Control Frames


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


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


802.2 SNAP

3 Byte

OUI

2 Byte

PrID


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


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


GFP & Ethernet MAC Payload

tHECType

PLIcHEC



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


22220-60

Bytes

ControlAddress

Page 147

ControlPPP Type

PPP Information

Pad


21

4

GFP Payload

AsClient

PPP/HDLC Frame GFP-F Frame

ControlPPP Type

PPP Information

Pad


PPP Payload

PPP Protocol

Bytes

1-21

tHECType

PLIcHEC


22220-60

Bytes

PPP Protocol

Page 148

PPP Information

PPP Padding (optional)


21

4

GFP Payload

AsClient

PPP/HDLC Frame GFP-F Frame

PPP Information

PPP Padding (optional)


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


Page 158


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

Page 166

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

Page 167

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!

Page 168

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?

Page 170

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

Documents

Training New SDH All