The basic format of an SDH signal allows it to carry many different services in its VC because SDH signal is bandwidth-flexible. This capability allows the transmission of high-speed packet-switched services, ATM, contribution video, and distribution video. However, SDH still permits transport and networking at the 2 Mbit/s, 34 Mbit/s, and 140 Mbit/s levels, accommodating the existing digital hierarchy signals. In addition, SDH supports the transport of signals based on the 1.5 Mbit/s hierarchy.

The STM-1 frame is the basic transmission format for SDH. The frame lasts for 125 microseconds, therefore, there are 8000 frames per second. The STM-1 frame consists of overhead plus a Virtual Container (VC) capacity.

The SDH frame consists of 270 columns. The first nine columns of each frame make up the Section Overhead, and the last 261 columns make up the VC capacity. The VC plus the pointers (H1, H2, H3 bytes) are called the Administrative Unit (AU). Carried within the VC capacity, which has its own frame structure of nine rows and 261 columns, is the Path Overhead and the Container. The first column is for Path Overhead; it is followed by the payload container, which can itself carry other containers. VCs can have any phase alignment within the Administrative Unit, and this alignment is indicated by the Pointer in row four. Within the Section Overhead, the first three rows are used for the Regenerator Section Overhead, and the last five rows are used for the Multiplex Section Overhead. The STM frame is transmitted in a byte-serial fashion, row-by-row, and is scrambled immediately prior to transmission to ensure adequate clock timing content for downstream regenerators.

• Structure Agnostic TDM over Packet (SAToP) (RFC 4553) – SAToP mode is used to encapsulate T1/E1 or T3/E3 unstructured (unchannelized) services over packet switched networks. In SAToP mode, the bytes are sent out as they arrive on the TDM line. Bytes do not have to be aligned with any framing.

  In this mode, the interface is considered as a continuous framed bit stream. The packetization of the stream is done according to IETF RFC 4553. All signaling is carried transparently as a part of a bit stream.

• Circuit Emulation Service over Packet (CEP) (RFC 4842) - CEP mode is used to encapsulate SDH payload envelopes (SPEs) like VC11, VC12, VC4, or VC4-Nc over PSN. In this mode, the bytes from the corresponding SPE are sent out as they arrive on the TDM line. The interface is considered as a continuous framed bit stream. The packetization of the stream is done according to IETF RFC 4842.

A Synchronous Transport Module (STM) signal is the Synchronous Digital Hierarchy (SDH) equivalent of the SONET STS. In this document, STM term refers to both path widths and optical line rates. The paths within an STM signals are called administrative units (AUs).

An AU is the information structure that provides adaptation between the higher-order path layer and the multiplex section layer. It consists of an information payload (the higher-order VC) and an AU pointer, which indicates the offset of the payload frame start relative to the multiplex section frame start.

The AU-3 pointer is composed of 3 bytes; the AU-4 pointer is composed of 9 bytes.

The payload of the STM-1 frame consists of one AU-4 unit or three AU-3 units.

Augment Mapping

The supported modes of SDH are:

• AU-4-16c (VC4-16c)

• AU-4-4c (VC4-4c)

• AU-4 (VC4)

• AU-4 — TUG-3 — VC-3 — DS3

• AU-4 — TUG-3 — VC-3 — E3

• AU-4 — TUG-3 — TUG-2 — VC-11 — T1

• AU-4 — TUG-3 — TUG-2 — VC-12 — E1

• AU-4 — TUG-3 — TUG-2 — VC-11

• AU-4 — TUG-3 — TUG-2 — VC-12

• AU-3 — VC-3 — DS3

• AU-3 — TUG-2 — VC-11 — T1

• AU-3 — TUG-2 — VC-12 — E1

• AU-3 — TUG-2 — VC-11

• AU-3 — TUG-2 — VC-12

• AU-3 — VC-3 — E3

This section describes the configuration of modes under AU-4 mapping.

This section describes the configuration of modes under AU-3 mapping.

Sets the SDH overhead bytes in the frame header to a specific standards requirement, or to ensure interoperability with equipment from another vendors.

• J0 — Sets the J0 or C1 byte value in the SDH section overhead.

  Note	The supported values of J0 are 1 byte, 16 bytes, and 64 bytes.

• S1S0 — Sets the SS bits value of the H1 byte in the SDH line overhead.

Set the path BER threshold values.

• b1-tca — Enables Bit Error Rate (BER) threshold crossing alerts for B1.

• b2-tca — Enables BER threshold crossing alerts for B2.

• sd-ber — Enables the threshold of the Signal Degrade (SD) BER that is used to trigger a signal degrade alarm.

• sf-ber — Configures the threshold of the Signal Failure (SF) BER that is used to trigger a link state change.

Sets a loopback to test the SDH port.

• local — Loops the signal from Tx to Rx path. Sends alarm indication signal (AIS) to network.

• network — Loops the signal from Rx to Tx path.

Enables automatic insertion of a Line Alarm Indication Signal (LAIS) in the sent SDH signal whenever the SDH port enters the administrative shutdown state.

Disables the interface.

Enables reporting for all or selected alarms.

This section describes the configuration of SDH path parameters.

The BERT patterns on the 1-Port OC-48 or 4-Port OC-12/OC-3 interface module are:

Note

If All 1's BERT pattern is tested on the system side, then ensure that you need to start all 1's pattern from both sides of the end points. Configuring BERT on one side and loopback on other side of the end points is not supported. The router treats all 1's pattern as AIS alarm and BERT will not come in sync with the other side configuration of the end point.

To configure BERT in modes VC-4 and VC Nc:

configure terminal
controller sdh 0/0/16
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
mode vc4
clock source internal
bert pattern 2^15 internal 10 direction [line | system]

To configure E1 Bert:

enable
configure terminal
controller MediaType 0/0/16
mode sdh
controller sdh 0/0/16
rate stm4
au-3 1
mode vc1x
tug-2 1 payload vc12
e1 1 bert pattern 2^11 interval 10
end

To configure T1 Bert:

enable
configure terminal
controller sdh 0/0/16
rate stm4
au-3 1
mode vc1x
tug-2 1 payload vc11
t1 1 bert pattern 2^11 interval 10
end

To configure BERT in Mode T3/E3 for both AUG mapping AU-3 and AU-4:

configure terminal
controller sdh 0/0/16
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
mode tug-3
clock source internal
tug-3 1
mode t3
threshold b3-tca 0
overhead c2 0
t3 clock source internal
t3 bert pattern 2^15 internal 10 direction [line | system]

To configure BERT in mode VC-1x for both AUG mapping AU-3 and AU-4:

configure terminal
controller sdh 0/0/16
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
mode tug-3
clock source internal
tug-3 1
mode vc-1x
tug-2 1 payload VC11
vc 1 bert pattern 2^15 internal 10 direction [line | system]

• Ensure that you have set up BERT engine before injecting BERT Errors.

• The BERT Error Injection once configured cannot be removed.

• BERT Error Injection is not supported on the SONET unframed mode.

• A maximum of 16 BERT engines are supported per LOTR card.

• You can configure a maximum of 255 BERT Error counts on the IM.

• BERT Error Injection is not supported on the following modes:

  • SONET: Unframed, STS-3C, STS-12C, STS-48C

  • SDH: VC4-4C, VC4-16C, AU3-V3, AU4-VC4

To configure T1/E1 parameters:

enable
configure terminal
controller sdh 0/0/16
rate stm4
au-3 1
mode vc1x
tug-2 1 payload vc11
t1 1 loopback [local | network line]
t1 1 clock source [line | internal | recovered]
end

Note	Loopback network payload is not supported. This is applicable for AU-4 Vc-1x and AU-3 Vc-1x modes.

Note	If T1/E1 is enabled on a particular J/K/L/M, you can only configure overhead and threshold for that J/K/L/M value.

To configure SDH T3/E3 parameters configuration:

enable
configure terminal
controller sdh 0/0/16
rate stm4
au-4 1
mode tug 3
tug-3 1
mode e3
e3 1 clock source [line | internal | recovered]
e3 framing [m13 | c-bit ] (applicable to for mode e3)
e3 1 loopback [local | network line]
e3 bert pattern 0s interval 2
tug-3 2
mode t3
t3 1 clock source [line | internal | recovered]
t3 framing [m13 | c-bit ] (applicable to for mode t3)
t3 1 loopback [local | network line]
t3 bert pattern 0s interval 2
end

Note	This is applicable to AUG mappaing AU-4 mode T3 and AU-3 mode T3.

To configure VC parameters:

enable
configure terminal
controller sdh 0/0/16
rate stm4
au-3 1
mode vc1x
tug-2 1 payload vc11
vc 1 loopback [local | network]
vc 1 clock source internal
vc 1 overhead j2 expected [16  | 64]
vc 1 overhead j2 expected message STRING
vc 1 overhead j2 tx [16  | 64]
vc 1 overhead j2 tx message STRING
vc 1 overhead v5 [0 - 7]
vc 1 [threshold bip2-sd 4 | threshold bip2-sf  4 | threshold bip2-tca 9]
end

Note	v5 overhead should match with the far end tx v5.

• E1 and E3 loopback remote are not supported until Cisco IOS XE Fuji 16.9.4 release. Starting from Cisco IOS XE Fuji 16.9.5 release, E1 and E3 loopback remote are supported.

• IBOC loopcode configuration is not supported when CESoP or SATOP (framed or unframed) is configured.

• ESF loopcode configuration is not supported when SAToP is configured.

To set T1 loopback remote iboc fac1/fac2/csu for OCX in SDH, perform the following tasks in global configuration mode:

enable
configure terminal
controller sdh 0/2/0
mode vc1x
tug-2 1 payload vc1x
t1 1 loopback remote iboc {fac1 | fac2 | csu}

To set T1 loopback remote iboc esf line csu/esf payload for OCX in SDH, perform the following tasks in global configuration mode:

enable
configure terminal
controller sdh 0/2/0
mode vc1x
tug-2 1 payload vc1x
t1 1 loopback remote esf {line csu | payload}

To set T3 loopback remote line/payload for OCX in SDH, perform the following tasks in global configuration mode:

enable
configure terminal
controller sdh 0/2/0
mode t3
t3 loopback remote {line | payload}

Note	loopback remote esf line niu is not supported.

Use the following command to check the T1 loopback remote configuration:

router# show run | sec 0/2/0
controller SDH 0/2/0
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
  clock source internal
 mode tug-3
  tug-3 1
   mode VC1x
   tug-2 1 payload VC11
    t1 1 Loopback remote iboc fac1

Use the following command to verify the T1 loopback remote configuration:

Router(config-ctrlr-tug2-vcx)#do show controller sdh 0/2/0 | be T1 1
AU-4 1, TUG-3 1, TUG-2 1, T1 1 (C-11 1/1/1/1) is up
  timeslots: 
  Configured for NIU FAC1 Line Loopback with IBOC
  Currently in Inband Remotely Line Looped
  Receiver has no alarms.
  Framing is SF, Clock Source is Internal
  Data in current interval (250 seconds elapsed):
   Near End                                      
     0 Line Code Violations, 0 Path Code Violations
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs       
     0 Unavailable Secs, 0 Stuffed Secs                           
     0 Path Failures, 0 SEF/AIS Secs                              
   Far End                                                        
     0 Line Code Violations, 0 Path Code Violations               
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs       
     0 Unavailable Secs 0 Path Failures                           
  Data in Interval 1:                                             
   Near End                                                       
     0 Line Code Violations, 0 Path Code Violations               
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     2 Errored Secs, 0 Bursty Err Secs, 2 Severely Err Secs       
     0 Unavailable Secs, 0 Stuffed Secs                           
     1 Path Failures, 2 SEF/AIS Secs                              
   Far End                                                        
     0 Line Code Violations, 0 Path Code Violations               
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     3 Errored Secs, 0 Bursty Err Secs, 3 Severely Err Secs       
     0 Unavailable Secs 0 Path Failures                           
  Total Data (last 1 15 minute intervals):                        
   Near End                                                       
     0 Line Code Violations,0 Path Code Violations,               
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
     2 Errored Secs, 0 Bursty Err Secs, 2 Severely Err Secs        
     0 Unavailable Secs, 0 Stuffed Secs                            
     1 Path Failures, 2 SEF/AIS Secs                               
   Far End                                                         
     0 Line Code Violations,0 Path Code Violations                 
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
     3 Errored Secs, 0 Bursty Err Secs, 3 Severely Err Secs        
     0 Unavailable Secs, 0 Path Failures 

Use the following command to check the T3 loopback remote configuration:

Router#show run | sec 0/4/7
platform enable controller MediaType 0/4/7 oc3
controller MediaType 0/4/7
mode sdh
controller SDH 0/4/7
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
  clock source internal
  mode tug-3
  tug-3 1
   mode T3
   t3 clock source internal
   t3 framing c-bit
   t3 loopback remote line

Use the following command to verify the T3 loopback remote configuration:

Router#show controll sdh 0/4/7 | be T3          
SDH 0/4/7.1/1 T3 is up. (Configured for Remotely Looped)
  Hardware is 
  Applique type is T3
  Receiver has no alarms.
  Data in current interval (240 seconds elapsed):                              
   Near End                                                                    
     0 Line Code Violations, 0 P-bit Coding Violations                         
     0 C-bit Coding Violations, 0 P-bit Err Secs                               
     0 P-bit Severely Err Secs, 0 Severely Err Framing Secs                    
     0 Unavailable Secs, 0 Line Errored Secs                                   
     0 C-bit Errored Secs, 0 C-bit Severely Errored Secs                       
     0 Severely Errored Line Secs, 0 Path Failures                             
     0 AIS Defect Secs, 0 LOS Defect Secs                                      
   Far End                                                                     
     0 Errored Secs, 0 Severely Errored Secs                                   
     0 C-bit Unavailable Secs, 0 Path Failures                                 
     0 Code Violations, 0 Service Affecting Secs                               
  Data in Interval 1:                                                          
   Near End                                                                    
     0 Line Code Violations, 0 P-bit Coding Violations                         
     0 C-bit Coding Violations, 0 P-bit Err Secs                               
     0 P-bit Severely Err Secs, 0 Severely Err Framing Secs                    
     20 Unavailable Secs, 20 Line Errored Secs                                 
     0 C-bit Errored Secs, 0 C-bit Severely Errored Secs                       
     20 Severely Errored Line Secs, 1 Path Failures                            
     0 AIS Defect Secs, 20 LOS Defect Secs                                     
   Far End                                                                     
     0 Errored Secs, 0 Severely Errored Secs                                   
     0 C-bit Unavailable Secs, 0 Path Failures                                 
     0 Code Violations, 0 Service Affecting Secs                               
  Total Data (last 1 15 minute intervals):                                     
   Near End                                                                    
     0 Line Code Violations, 0 P-bit Coding Violations,                        
     0 C-bit Coding Violations, 0 P-bit Err Secs,                              
     0 P-bit Severely Err Secs, 0 Severely Err Framing Secs,                   
     20 Unavailable Secs, 20 Line Errored Secs,                                
     0 C-bit Errored Secs, 0 C-bit Severely Errored Secs                       
     20 Severely Errored Line Secs, 1 path failures                            
     0 AIS Defect Secs, 20 LOS Defect Secs                                     
   Far End                                                                     
     0 Errored Secs, 0 Severely Errored Secs                                   
     0 C-bit Unavailable Secs, 0 Path Failures                                 
     0 Code Violations, 0 Service Affecting Secs                               

T1 1 is up
  timeslots: 
  FDL per AT&T 54016 spec.
  No alarms detected.     
  Framing is ESF, Clock Source is Internal
  Data in current interval (250 seconds elapsed):
   Near End                                      
     0 Line Code Violations, 0 Path Code Violations
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs       
     0 Unavailable Secs, 0 Stuffed Secs                           
     0 Path Failures, 0 SEF/AIS Secs                              
   Far End                                                        
     0 Line Code Violations, 0 Path Code Violations               
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs       
     0 Unavailable Secs 0 Path Failures                           
  Data in Interval 1:                                             
   Near End                                                       
     0 Line Code Violations, 0 Path Code Violations               
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     2 Errored Secs, 0 Bursty Err Secs, 2 Severely Err Secs       
     0 Unavailable Secs, 0 Stuffed Secs                           
     1 Path Failures, 2 SEF/AIS Secs                              
   Far End                                                        
     0 Line Code Violations, 0 Path Code Violations               
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     3 Errored Secs, 0 Bursty Err Secs, 3 Severely Err Secs       
     0 Unavailable Secs 0 Path Failures                           
  Total Data (last 1 15 minute intervals):                        
   Near End                                                       
     0 Line Code Violations,0 Path Code Violations,               
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
     2 Errored Secs, 0 Bursty Err Secs, 2 Severely Err Secs        
     0 Unavailable Secs, 0 Stuffed Secs                            
     1 Path Failures, 2 SEF/AIS Secs                               
   Far End                                                         
     0 Line Code Violations,0 Path Code Violations                 
     0 Slip Secs, 2 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
     3 Errored Secs, 0 Bursty Err Secs, 3 Severely Err Secs        
     0 Unavailable Secs, 0 Path Failures