Cisco NCS 2000 Series SVO Configuration Guide, Release 12.2
Bias-Free Language
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This chapter describes the tasks related to node configuration in Cisco NCS 2000 SVO.
Internal Patch Cords
Internal patchcords provide virtual links between two termination points of the network. A
termination point may be an OSC port, a transponder or muxponder
trunk port, a line port, or a passive device port.
Manage Internal Patch Cords
Use this task to create, modify, view, or delete internal patchcords in the node.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click the Optical Configuration > Internal Patch Cords tabs.
Step 3
Perform these steps, as needed.
To add a new internal patch cord, perform these steps:
Click the + button.
The Create Internal Patch Cord dialog
box appears. It displays the From and
To columns indicating the two
termination points.
Choose the Type of the patch cord from
the drop-down list. The options are chassis or passive unit.
Choose the UID, Slot, and Port types from the drop-down lists.
Note
If the selected Type in the previous step is a passive
unit, the Slot field is not displayed.
Check the Bi-directional check box if
you want to make the patch cord bidirectional.
Click Apply.
The internal patch cord is created and added to the table that displays the following information:
From—Specifies the location from where the connection originates.
To—Specifies the location where the connection terminates.
Type—Specifies the type of
internal patch cord. Possible values are Transport
and Add-Drop.
To delete the internal patch cords, perform these steps:
Check the check boxes corresponding to the internal patch cords you want to delete.
Click the - button to delete the
selected patch cord.
A confirmation message appears.
Click Yes.
The internal patch cord is deleted from the table.
Step 4
(Optional) Click the Export to Excel button to export
the information to an Excel sheet.
Connection Verification
The connection verification feature measures power levels and verifies the optical cables
and patchcords in a node for the following:
Connectivity: Checks whether the cable is connected.
Insertion Loss: Checks whether the cable loss is within expected value.
A 1567-nm connectivity check signal is generated and transmitted into the DMUX input port
of the 20-SMRFS-CV card by a dedicated laser source. This signal is detected by an
embedded photo diode to complete the connection verification.
Supported Cards and Passive Devices
The cards and passive devices that support connection verification are as
follows:
16-AD-CCOFS
20-SMRFS-CV
MF-DEG-5 and MF-DEG-5-CV
MF-MPO-16LC and MF-MPO-16LC-CV
MF-UPG-4 and MF-UPG-4-CV
100GS-CK-LC, 200G-CK-LC, and 400G-XP
The passive devices require loopback caps on unused ports. The CV version of the
passive devices is shipped with loopback caps.
Prerequisites
The connection verification feature works only if the following conditions are
met:
Flex nodes must be present.
Loopback caps must be installed on all the unused ports of the passive
devices.
At least one 20-SMRFS-CV card must be present in the node.
All sides of the node must have the 20-SMRFS-CV card to test all the cables
and patchcords.
All passive devices must be connected with a USB cable and associated, so
that power readings can be calculated.
Running the Connection Verification
The connection verification runs automatically at the following time intervals and
events:
20 minutes after boot or reboot of the first shelf controller
One minute after enabling the connection verification
Ten minutes after creation or deletion of patchcords
Ten minutes after creation or deletion of circuits
Every six hours
Benefits
The benefits of connection verification feature are as follows:
Validates the 20-SMRFS-CV card connectivity with local Add/Drop or other
ROADM elements.
Detects any incorrect cabling in the ROADM network element.
Collects insertion losses of each optical path inside the network element to
detect possible failures.
Verify Connections in Optical Cables
Use this task to verify the optical
interconnections between the optical cards inside the flex ROADM node.
Click the hamburger icon at the top-left of the page, and select
Node Configuration.
Step 2
Click the Optical Configuration > Connection Verification tabs.
Step 3
Check the Enable Verification check box to
enable connection verification at the node level.
Step 4
View the following information displayed in the Connection
Verification pane:
From—Displays the
source slot for connection verification.
To—Displays the
destination slot for connection verification.
Connectivity
Verification—Displays connectivity status. This information is
summarized and displayed for any patchcord in the MPO cable. The
different status includes:
Connected—Cable or patchcord is connected.
Not Connected—Cable or patchcord is disconnected.
Disabled—Cable or patchcord is excluded from connection
verification.
Not Measurable—Power source is not detected; cable or
patchcord cannot be tested for connection verification.
Not Verified—Cable or patchcord is not tested for connection
verification. This is the default status upon first boot.
Connectivity Last
Change—Displays the date and time when the connectivity information
was previously changed.
Loss
Verification—Displays insertion loss verification status that is one
of the following:
Not Verified—Cable or patchcord is not tested for insertion
loss verification. This is the default status upon first
boot.
Not Measurable—Power source is not detected; cable or
patchcord cannot be tested for insertion loss verification.
OK—Cable or patchcord insertion loss is within expected
value.
Degrade—Cable or patchcord insertion loss is degrading.
When the insertion loss is greater than the Insertion Loss
Degrade threshold and less than the Insertion Loss Fail
threshold, the status of insertion loss verification is
Degrade. The Insertion Loss Degrade threshold is available
at the bottom of the Connection
Verification pane.
Fail—Cable or patchcord insertion loss crossed the fail
threshold.
When the insertion loss is greater than the Insertion Loss
Fail threshold, the status of insertion loss verification is
Fail. The Insertion Loss Fail threshold is available at the
bottom of the Connection Verification
pane.
Disabled—Cable or patchcord is excluded from insertion loss
verification.
Loss Last
Changed—Displays the date and time when the insertion loss
verification information was previously changed.
Excess Loss
[dB]—Displays the excess loss versus the maximum specified loss for
the cable under test. When the shelf controller reboots, the
information in the Excess Loss column is lost.
Last Run—Displays the date and
time when the connection verification and insertion loss
verification were previously run. When the shelf controller reboots,
the information in the Last Run column is lost.
Ack—Displays the alarm
acknowledgment information for a specific fiber. The possible values
are true or false.
Is Reachable—Indicates whether the connectivity is available to the
patchcords and MPO cables. The possible values are true or
false.
Combined Loss—Indicates whether two or more patch cords are
considered as a chain from the connection verification point of
view. The possible values are true or false.
Step 5
Perform these steps, as needed.
Click Abort CV to stop the connection or
insertion loss verification at any point.
Click Verify
Connectivity to perform connection verification on all
the patchcords and MPO cables (default behavior) or choose the required
patchcords and MPO cables and click Verify Connectivity to
perform connection verification on the selected patchcords and MPO
cables.
The confirmation message appears that lists all the links or the
selected links accordingly.
Click Verify Loss
to perform insertion loss verification on all the patchcords and MPO
cables (default behavior) or choose the required patchcords and MPO
cables and click Verify
Loss to perform insertion loss verification on the
selected patchcords and MPO cables.
The confirmation message appears that lists all the links or the
selected links accordingly.
Click Ack to acknowledge the insertion loss
verification result related to the selected MPO cables or patchcords.
This button allows MPO cable or patch cord to operate beyond the
insertion loss thresholds without raising an alarm. If all the
insertion loss verification problems on the current node are
acknowledged, the consequent alarm on the node is cleared.
Click Clear Ack to clear the acknowledgment on
the selected MPO cable or patchcord. The insertion loss verification
result becomes Fail or Degrade. This operation can raise the
IPC-VERIFICATION-FAIL or IPC-VERIFICATION-DEGRADE alarm on the node.
Enter the Insertion Loss Fail threshold in the Fail field and the
Insertion Loss Degrade threshold in the Degrade field.
The IPC-Verification-Running condition is raised when connection or
insertion loss verification is started. The default values of
Insertion Loss Fail threshold and Insertion Loss Degrade threshold
parameters are 4 and 1.5 dB respectively. These two default
thresholds are used to generate the alarms.
Click Refresh to refresh the
connection verification information.
Step 6
Click Apply to apply the changes.
Step 7
After connection verification, perform these
steps, as needed:
If the insertion loss verification results for a patchcord are Fail or
Degrade, perform these steps:
Remove the patchcord.
Clean the patch cord.
Install the patchcord.
Perform the insertion loss verification step again.
If the patchcord status is Not Connected, it raises the IPC-VERIFICATION-FAIL
alarm on the node. To clear this condition, perform these steps:
Ensure that the patchcords are installed correctly on both the ends.
Perform the insertion loss verification step again.
Replace the patchcords if the alarm still exists.
If the IPC-LOOPBACK-MISS alarm is raised on any port, perform these
steps:
Identify the port with IPC-LOOPBACK-MISS alarm.
Check whether the loopback is installed on the port.
If the loopback is correctly installed, perform the insertion loss
verification step again.
Replace the loopback if the alarm still exists.
Optical Degrees
From a topological point of view, all the DWDM units that are equipped in a node belong to a
side. A side can be identified by a letter, or by the ports that are physically
connected to the spans. A node can be connected to a maximum of 20 different spans. Each
side identifies one of the spans to which the node is connected.
Manage Optical Degrees
Use this task to create, view, modify, or delete optical degrees in the node.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click the Optical Configuration > Optical Degree tabs.
Step 3
Perform these steps, as needed.
To create an optical degree, perform these steps:
Click the + button.
The Create Optical Degree dialog box
appears.
Select the Degree, Line In, and Line Out, values from their respective drop-down lists.
(Optional) Enter a description in the Description field.
Click Apply.
Note
You can only create a maximum of 20 optical degrees. The
optical degree is created and added to the table that
displays the following information.
Degree—Specifies the optical span of the side.
Description—Specifies the
description as entered while creating the optical
degree.
Line In—Specifies line in settings.
Line Out—Specifies line out settings.
Connected-to
(IP/Degree)—Specifies the IP address and
the optical degree of the remote SVO instance that
is connected on the other side of the span.
Span Validation—Specifies whether the span can be used by the GMPLS algorithm for channel routing and validation. Values are True or False.
Channel Grid—Specifies the type of grid. Values are Flexible-Grid or Fixed-Grid.
Channel Spacing—Specifies the
minimum frequency spacing between two adjacent
channels in the optical grid. Values are 100 or 50
GHz.
Spectrum Occupancy—Specifies a
percentage of the spectral density (the ratio of the
C-band used by the carrier versus the total
bandwidth). The valid range is 50% to 91%.
Domain Type—Specifies the algorithm that is active on the span. Values are LOGO or LEGACY.
To modify any one of the optical degree parameters described below degree, perform the required step as needed:
To modify the span validation of an optical degree, select a value from the drop-down list in the Span Validation column and click Apply.
To enable Fixed-Grid with LOGO on an optical degree, go to the related cell in the Channel Spacing column, select 50 or 100 from the drop-down list, and click Apply.
The Channel Grid value changes to Fixed-Grid and the Domain Type value changes to LOGO.
To enable Flexible-Grid with LOGO on an optical degree, go to the related cell in the Spectrum Occupancy column, enter a valid value, and click Apply.
The Channel Grid value changes to Flexible-Grid and the Domain Type value changes to LOGO.
To change the Domain Type from LOGO to LEGACY, you must delete the optical degree and create it again.
To delete an optical degree, perform these steps:
Check the check box corresponding to the optical degree you want to delete.
Click the - button to delete the selected optical degree.
A confirmation message appears.
Click Yes.
The optical degree is deleted from the table.
Step 4
(Optional) Click the Export to Excel button to export
the information to an Excel sheet.
Fiber Attributes
The Fiber Attributes tab lists the attributes of the fibers that are connected to the optical side.
Manage Fiber Attributes
Use this task to create, view, modify, or delete fiber attributes of a span.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click the Optical Configuration > Fiber Attributes tabs.
Step 3
Perform these steps, as needed.
To create a fiber attribute, perform these steps:
Click the + button.
The Create Fiber Attributes dialog box
appears.
Enter the fiber ID in the Fiber ID field.
Select the Fiber ID, Degree, Fiber Type, Length, PMD, Attenuator In, and Attenuator Out from their respective scroll-lists.
Click Apply.
The fiber attribute is created and added to the table that displays the following information.
Degree—Specifies the optical side.
Fiber ID—Specifies the fiber number in the duct.
Fiber Type—Specifies the type of fiber deployed.
Length—Specifies the length of
the optical span in kms or miles.
PMD—Specifies the polarization
mode dispersion (PMD) fiber coefficient in ps/sqrt
(km).
Attenuator In—Specifies the input attenuation in dB between the node output port (typically LINE-TX port) and the input of the fiber span.
The span may include patchcords, attenuators, and patch panels.
Attenuator Out—Specifies the output attenuation in dB between the node input port (typically LINE-RX port) and the output of the fiber span.
The span may include patchcords, attenuators, and patch panels.
To modify the fiber attributes, perform these steps:
To modify the Fiber Type, Length, PMD, Attenuator In,
Attenuator Out, or PMD values on an optical degree, go to
the related cell in the related column, select a value from
the drop-down list, and click
Apply.
A confirmation message appears. Click Yes.
To delete a fiber attribute, perform these steps:
Check the check box corresponding to the fiber attribute you want to delete.
Click the - button to delete the
selected fiber attribute.
A confirmation message appears.
Click Yes.
The fiber attribute is deleted from the table.
Step 4
(Optional) Click the Export to Excel button to export
the information to an Excel sheet.
OSC
OSC is a point-to-point communication channel that connects two consecutive nodes. The OSC
carries a supervisory data channel and synchronizes clocking at
network nodes. The OSC also carries a user data channel. Before
provisioning OSC terminations on TNC ports carrying Fast
Ethernet (FE) payloads, ensure that you set the ALS mode on
these ports to Disabled.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click the Optical Configuration > Optical Degree Power Monitoring tabs.
Step 3
Choose the Optical Degree from the drop-down list.
Step 4
Click Refresh.
Link Power Control
The Link Power Control (LPC) feature performs the following functions:
Maintains constant per channel power when desired or accidental changes to the number of channels occur. Constant per channel
power increases optical network resilience.
Compensates for optical network degradation (aging effects).
Simplifies the installation and upgrade of DWDM optical networks by automatically calculating the amplifier setpoints.
Note
LPC algorithms manage the optical parameters of the line cards.
Amplifier software uses a control gain loop with
fast transient suppression to keep the channel power constant regardless of any
changes in the number of channels. Amplifiers monitor the changes to the input power
and change the output power proportionately according to the calculated gain
setpoint. The shelf controller software emulates the control output power loop to
adjust for fiber degradation. To perform this function, the control card must know
the channel distribution, which is provided by a signaling protocol, and the
expected per channel power, which you can provision. The control card compares the
actual amplifier output power with the expected amplifier output power and modifies
the setpoints if any discrepancies occur.
LPC at the Shelf Controller Layer
Amplifiers are managed through software to monitor
changes in the input power. Changes in the network characteristics have an impact on
the amplifier input power. Changes in the input power are compensated for by only
modifying the original calculated gain, because input power changes imply changes in
the span loss. As a consequence, the gain to span loss established at the amplifier
start-up is no longer satisfied, as shown in the following figure.
Figure 1. Using Amplifier Gain
Adjustment to Compensate for System Degradation
In the preceding figure, Node 1 and Node 2 are equipped with booster amplifiers and
preamplifiers. The input power received at the preamplifier on Node 2 (Pin2) depends
on the total power launched by the booster amplifier on Node1, Pout1(n) (where n is
the number of channels), and the effect of the span attenuation (L) between the two
nodes. Span loss changes due to aging fiber and components or changes in operating
conditions. The power into Node 2 is given by the following formula:
Pin2 = LPout1(n)
The phase gain of the preamplifier on Node 2
(GPre-2) is set during provisioning to compensate for the span loss so that the Node
2 preamplifier output power (Pout-Pre-2) is equal to the original transmitted power,
as represented in the following formula:
Pout-Pre-2 = L x GPre-2 x Pout1(n)
In cases of system degradation, the power received
at Node 2 decreases due to the change of span insertion loss (from L to L'). As a
consequence of the preamplifier gain control working mode, the Node 2 preamplifier
output power (Pout-Pre-2) also decreases. The goal of LPC at the shelf controller
layer is simply to detect if an amplifier output change is needed because of changes
in the number of channels or to other factors. If factors other than the "changes in
the number of channels" factor occur, LPC provisions a new gain at the Node 2
preamplifier (GPre-2') to compensate for the new span loss, as shown in the formula:
Generalizing on the preceding relationship, LPC is
able to compensate for system degradation by adjusting working amplifier gain or
variable optical attenuation (VOA) and to eliminate the difference between the power
value read by the photodiodes and the expected power value. The expected power
values are calculated using:
Provisioned per channel power value
Channel distribution (the number of express, add, and drop channels in the node)
ASE estimation
Channel distribution is determined by the sum of
the provisioned and failed channels. Information about provisioned wavelengths is
sent to LPC on the applicable nodes during the circuit creation. Information about
failed channels is collected through a signaling protocol that monitors alarms on
ports in the applicable nodes and distributes that information to all the other
nodes in the network.
ASE calculations purify the noise from the power
level that is reported from the photodiode. Each amplifier can compensate for its
own noise, but cascaded amplifiers cannot compensate for ASE generated by preceding
nodes. The ASE effect increases when the number of channels decreases; therefore, a
correction factor must be calculated in each amplifier of the ring to compensate for
ASE build-up.
LPC is a network-level feature that is distributed among different nodes. An LPC domain is a set of nodes that are regulated
by the same instance of LPC at the network level. An LPC domain optically identifies a network portion that can be independently
regulated. Every domain is terminated by two node sides residing on a terminal node, ROADM node, hub node, line termination
meshed node, or an XC termination meshed node. An optical network can be divided into several different domains, with the
following characteristics:
Every domain is terminated by two node sides. The node sides terminating domains are:
Terminal node (any type)
ROADM node
Cross-connect (XC) termination mesh node
Line termination mesh node
LPC domains are shown in the GUI.
Inside a domain, the LPC algorithm designates a
primary node that is responsible for starting LPC hourly or every time a new circuit
is provisioned or removed. Every time the primary node signals LPC to start, gain
and VOA setpoints are evaluated on all nodes in the network. If corrections are
needed in different nodes, they are always performed sequentially following the
optical paths starting from the primary node.
LPC corrects the power level only if the variation
exceeds the hysteresis thresholds of +/– 0.5 dB. Any power level fluctuation within
the threshold range is skipped because it is considered negligible. Because LPC is
designed to follow slow time events, it skips corrections greater than 3 dB. This is
the typical total aging margin that is provisioned during the network design phase.
After you provision the first channel or the amplifiers are turned up for the first
time, LPC does not apply the 3-dB rule. In this case, LPC corrects all the power
differences to turn up the node.
To avoid large power fluctuations, LPC adjusts
power levels incrementally. The maximum power correction is +/– 0.5 dB. This is
applied to each iteration until the optimal power level is reached. For example, a
gain deviation of 2 dB is corrected in four steps. Each of the four steps requires a
complete LPC check on every node in the LPC domain. LPC can correct up to a maximum
of 3 dB on an hourly basis. If degradation occurs over a longer time period, LPC
compensates for it by using all margins that you provision during installation.
LPC can be manually disabled. In addition, LPC automatically disables itself when:
A Hardware Fail (HF) alarm is raised by any
card in any of the domain nodes.
A Mismatch Equipment Alarm (MEA) is raised by any card in any of the domain nodes.
An Improper Removal (IMPROPRMVL) alarm is raised by any card in any of the domain nodes.
Gain Degrade (GAIN-HDEG), Power Degrade (OPWR-HDEG), and Power Fail (PWR-FAIL) alarms are raised by the output port of any
amplifier card in any of the domain nodes.
A VOA degrade or fail alarm is raised by any of the cards in any of the domain nodes.
The signaling protocol detects that one of the LPC instances in any of the domain nodes is no longer reachable.
LPC raises the following minor, non-service-affecting alarms:
APC Out of Range—LPC cannot assign a new setpoint for a parameter that is allocated to a port because the new setpoint exceeds
the parameter range.
APC Correction Skipped—LPC skipped a
correction to one parameter allocated to a port because the difference
between the expected and current values exceeds the +/– 3-dB security range.
LPC at the Amplifier Card Level
In constant gain mode, the amplifier power out control
loop performs the following input and output power calculations, where G represents
the gain and t represents time.
Pout (t) = G * Pin (t) (mW)
Pout (t) = G + Pin (t) (dB)
In a power-equalized optical system, the total input power is proportional to the number of channels. The amplifier software
compensates for any variation of the input power due to changes in the number of channels carried by the incoming signal.
Amplifier software identifies changes in the read
input power in two different instances, t1 and t2,
as change in the traffic is being carried. The
letters m and n in the following formula represent
two different channel numbers. Pin/ch represents
the input power per channel.
Pin (t1)= nPin/ch
Pin (t2) = mPin/ch
Amplifier software applies the variation in the input
power to the output power with reaction time that is a fraction of a millisecond.
This keeps the power constant on each channel at the output amplifier, even during a
channel upgrade or a fiber cut.
The per channel power and working mode (gain or power) are set by automatic node setup (ANS). The provisioning is conducted
on a per-degree basis.
Starting from the expected per channel power, the
amplifiers automatically calculate the gain setpoint after the first channel is
provisioned. An amplifier gain setpoint is calculated in order to make it equal to
the loss of the span preceding the amplifier itself. After the gain is calculated,
the setpoint is no longer changed by the amplifier. Amplifier gain is recalculated
every time the number of provisioned channels returns to zero. If you must force a
recalculation of the gain, move the number of channels back to zero.
Forcing Power Correction
A wrong use of maintenance procedures can lead the
system to raise the APC Correction Skipped alarm. The APC Correction Skipped alarm
strongly limits network management (for example, a new circuit cannot be converted
into In-Service (IS) state). The Force Power Correction
button available in the Node
Configuration > APC tab
helps the user to restore normal conditions by clearing the APC Correction Skipped
alarm. The Force Power Correction button must be used under
the Cisco TAC surveillance because its misuse can lead to traffic loss.
Disable Link Power Control
Use this task to disable Link Power Control.
Caution
When LPC is disabled, aging compensation is not applied and circuits cannot be
activated. Disable LPC only to perform specific troubleshooting or node
provisioning tasks. When the tasks are completed, enable and run LPC. Leaving
LPC disabled can cause traffic loss.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click the APC tab.
Step 3
Choose a degree and choose automatic-enabled from the Admin Status drop-down list.
Only degrees with Admin Status as force-disabled can be enabled.
Step 4
Click Apply.
Step 5
Verify that the Service Status field changes to enabled.
Span Loss Measurement
Span loss measurements (in dB) check the span loss and are useful whenever changes to the network
occur.
The span loss operational parameters are:
Measured By—Displays whether the span loss is measured by
the channel or Optical Service Channel (OSC). If a channel is not configured,
the span loss is measured by the OSC. After a SMR-20 or SMR-9 channel is
configured, the span loss is measured by the channel. An EDFA measures the span
loss based on circuits.
Measured Span Loss—Displays the measured span loss.
Measured Span Loss Accuracy—Displays the accuracy of the
span loss measurement. For example, if the measured span loss is 20 dB and the
displayed accuracy value is 2.5, the actual span loss could either be 19 or 21
dB.
Measured Time—Displays the time and date when the last span loss measured value is changed.
If there is a new network with SVO, the operational parameters list of span loss has two rows.
The first row displays the OSC-measured span loss details. After the channel is
configured, the second row is added, which displays the channel-measured span loss
details. After the channel is configured, only the channel-measured span loss details
are updated.
View or Modify Span Loss Parameters
Use this task to view or modify span loss parameters.
Note
If a channel or OSC is not configured, span loss measurement is not reported and the operational parameters list is empty.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click the Optical Configuration > Span Loss tabs.
A table is displayed with the following information:
Degree—Displays the side for which span loss information appears.
Measured By—Displays whether the measurement
was executed with or without channels. Values are OSC or
CHANNEL.
Min Exp. Span Loss (dB)—Displays the minimum expected span loss (in dB) for the incoming span.
Max Exp. Span Loss (dB)—Displays the maximum
executed span loss (in dB) for the incoming span.
Measured Span Loss (dB)—Displays the measured span loss value.
Measured Accuracy (dB)—Displays the resolution
or accuracy of the span loss measurement. The resolution is +/-1.5
dB if the measured span loss is 0–25 dB. The resolution is +/-2.5 dB
if the measured span loss is 25–38 dB.
Measured Time—Displays the time and date when the last span loss measured value is changed.
Step 3
Select a row and click Measure Span Loss.
A message appears. Click OK.
Step 4
Refresh the table to view the updated Measured Span
Loss, Measured Accuracy, and
Measured time.
Step 5
Modify the values for Min. Exp. Span Loss or
Max. Exp. Span Loss in dB. The range is from 0 to 99.
Step 6
Click Apply.
A confirmation message appears.
Step 7
Click Yes.
The span loss range is extended including the Accuracy value. A Span Loss Out
of Range condition is raised when the measured span loss is higher than the
extended range.
Step 8
(Optional) Click the Export to Excel button to export
the information to an Excel sheet.
Optical Cross-connect Management
Optical cross-connect (OXC) circuits establish connectivity between two optical nodes on a specified C-band wavelength. The
connection is made through the ports present on the wavelength selective switches, multiplexers, demultiplexer, and add/drop
cards. In an OXC circuit, the wavelength from a source interface port ingresses to a DWDM system and then egresses from the
DWDM system to the destination interface port. The OXC circuits are biredirectional in nature and are created using data models.
The administrative states are:
IS/Unlocked
IS,AINS/Unlocked,AutomaticInService
OOS,DSBLD/Locked,disabled
View Optical Cross-connect Circuits
Use this task to view the details of the optical cross-connects that are created for a node using data models.
Note
The optical cross-connects are read-only and cannot be modified.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Select the Optical Cross Connections tab.
The following details are displayed for each cross-connect.
Connection Label—Displays the name of the cross-connect.
Type—Displays the type of cross-connect. It is bidirectional.
Admin Status—Displays the admin state on the circuit.
Central Frequency (THz)—Displays the spectral position of the circuit.
Allocation Width (GHz)—Displays the bandwidth occupied by the service. The range is 25 to 300GHz.
Signal Width (GHz)—Displays the carrier
bandwidth.
Note
The payload bandwidth is lesser than the allocation bandwidth.
Path 1 End-points—Displays the source and
destination interfaces of the path.
Path 2 End-points—Displays the source and destination interfaces of the path.
To view Path 1 or Path 2, click the + icon to expand the cross-connect. Click the down arrow on the right to view the internal
details of Path 1 or Path 2. The details are:
Interface Name—Displays the interface name.
Optical Power—Displays the value of the optical power.
Power Degrade High—Displays the threshold for a maximum power degrade.
Power Degrade Low—Displays the threshold for a minimum power degrade.
Power Failure Low—Displays the threshold for power failure.
Optical Psd Setpoint (dBm/GHz)—Displays the optical power spectral density setpoint. This setpoint is independent of the width of the circuit.
Optical Power Setpoint—Displays optical power setpoint. This setpoint is scaled to the width of the circuit and matches the value of the optical
power parameter.
Step 3
(Optional) Click the Export to Excel button to export
the information to an Excel sheet.
Import the Cisco ONP Configuration File into SVO
You can import the configuration file (NETCONF file) exported from Cisco ONP. The file contains parameters for the node, shelf,
card type, port (including wavelength of the card), pluggable port module (PPM), and OTN and FEC parameters.
Caution
Verify that you have the correct Cisco ONP network file before you begin this procedure. The file has an XML extension and
a name that is assigned by your network planner. Check with your network planner or administrator if you have any questions.
Only the values present in XML format appear in the configuration file parameters. If the values are not in XML format, a
column appears blank. The XML file values are independently reported and do not affect any configuration changes that you
apply. Finally, the NETCONF file installs the ANS parameters that are calculated by Cisco ONP.
Use this task to import the Cisco ONP NETCONF file into SVO.
Click the hamburger icon at the top-left of the page, and select Node Configuration.
Step 2
Click Node Setup tab.
Step 3
Click Select Files, browse and select the NETCONF file exported from Cisco ONP.
Note
If you see an error in a pop-up window, validate the XML file and re import.
Step 4
If you want to export the XML file, click the Download Node Configuration as XML icon.
OTDR Support
Table 1. Feature History
Feature
Release Information
Description
OTDR Enhancements
Cisco NCS 2000 Release 12.2
The following OTDR enhancements are introduced to improve the user experience:
Choose either Hybrid or Fast mode for OTDR scan
Download OTDR scan configurations in .xls format
Print and download OTDR graph in JPEG or PNG formats
View the Event table below the graph with Event ID, Location (km), Magnitude (dB),and Type parameters
From R12.01 onwards, SVO supports TNCS-O and TNCS-2O cards for Optical Time Domain Reflectometer (OTDR) specific operations.
OTDR is used to detect faults in an optical fiber link of a communication network.
The OTDR feature on the TNCS-O and TNCS-2O cards lets you do the following:
Inspect the transmission fiber.
Identify discontinuities or defect on the fiber.
Measure the distance and magnitude of defects like insertion loss, reflection loss, and so on.
Monitor variations in scan values and configured threshold values periodically.
Note
OTDR does not support the placement of a bulk attenuator in its path. OTDR sends pulses of light and measures the reflected
light. Bulk attenuator hinders this mechanism. The attenuator reduces the dynamic range of OTDR, limiting its capability.
Another issue with bulk attenuator is that it has two reflective surfaces very close to each other which corrupts the OTDR
pulses.
If a bulk attenuator is placed near the OTDR faceplate, the OTDR may not measure beyond the attenuator. If lumped attenuation
is present beyond the attenuator, OTDR may erroneously declare that the fiber ends at that point. As per design, OTDR may
exhibit this behavior with 5 dB or more, of lumped attenuation.
Note
Once the OTDR port is initialized, it needs calibration every 24 hours for ORL measurement in Tx Direction. For this calibration,
ORL training is triggered automatically by the OTDR module. ORL training is performed in hybrid mode and it lasts for just
a few minutes. You cannot stop the trigger of this automatic ORL training.
OTDR Training
OTDR scan performances are improved using specific parameters of fiber such as span length, span loss, equipment insertion
loss, reflection contributions, and major events on the fiber. This calibration operation is called OTDR training.
OTDR training is executed with the following rules.
OTDR training is executed on both the Tx fiber and Rx fiber.
OTDR training results are used to execute the composite scan.
OTDR training is embedded in the scan operation.
OTDR training takes up to 2 minutes in fast mode and up to 10 minutes in hybrid mode.
OTDR training results in calibration file, fast span trace, and identification of the fiber end.
Note
High reflection location is not available if detected during Optical Return Loss (ORL) training.
Provision OTDR Ports
Use this task to provision OTDR ports on the TNCS-O and TNCS-2O control cards.
Click the hamburger icon at the top-left of the page and select Node Configuration.
Step 2
Click the OTDR > Provisioning tabs.
Step 3
Perform these steps as needed.
To add an OTDR port, click +Add.
In the Create OTDR dialog box, choose the Port.
Click Apply.
The OTDR port is created and added to the table that displays the following information:
Note
When you create an OTDR port, there are two entries with the status for direction Tx and the direction Rx.
Port―Displays the OTDR port name.
Direction―Displays the direction of the port (Rx or Tx).
Scan Status―Displays the status of the OTDR scan; for example, status-progress, status-failure, or status-idle.
Scan Progress―Displays the progress of the OTDR scan, in percentage.
OTDR Training Status―Displays the status of the OTDR training; for example, status-trained, and status-not-executed. The status
is unique for each direction.
ORL Training Status―Displays the status of the ORL
training. The status is unique for each
direction.
Scan Failure Message―Displays the reason for the scan failure.
High Reflection Location―Displays the location of high reflection that is detected when the scan fails.
ORL Threshold― Displays the threshold of the ORL measure. There is an alarm (Excessive ORL Measure) associated with this field.
Refractive Index―Displays the fiber refractive index, which depends on the installed fiber.
Backscatter―Displays the reflective light on the fiber, which is also dependent on the installed fiber.
Loss Sensitivity―Displays the limit under which the loss is not considered as real loss, in dB.
Reflection Sensitivity―Displays the limit under which the reflection is not considered as a real reflection, in dB.
(Optional) If you want to delete a port, select one of the entries (Tx or Rx), and click Delete.
Both entries (Tx and Rx) of the port are deleted.
Step 4
To run the OTDR scan, perform these steps:
(Optional) Set the following values, if required.
Absolute Alarm Thresholds for loss and reflection
Loss Sensitivity and
Reflection Sensitivity of the
fiber
Choose the OTDR port on which OTDR scan has to be performed.
Click Start.
"OTDR scan started" message appears.
Note
You can run only one scan at a time either in TX or RX direction, for each port. When you start a scan on direction TX, the
column that is related to TX direction is updated, and when you start the scan on RX, the other column is updated.
You can run scan on both ports (for example: ports 1 and 2 on TNCS-O, and ports 3 and 4 on TNCS-2O) at the same time.
You can perform as many scans as you want, but SVO database can retain only up to two Tx scans and two Rx scans for each port.
If you perform subsequent scans, the existing scan file is overwritten by the latest scan file. Hence, for each port, the
web user interface displays only up to two TX scans and two RX scans.
You can view the status of the scan under the Scan Status column.
Step 5
To view the OTDR scan traces, perform these steps:
Click the Traces tab.
To set a baseline, perform these steps:
From the Port drop-down list, choose one of the ports you have configured, to analyze.
From the Last Scan Traces drop-down list, choose the scan file that you want to analyze.
If the selected scan had desired results and you want to set the selected scan file as a baseline, click Baseline.
Click Yes to confirm.
Click Ok in the Action dialog box.
The baseline is saved. You can have one baseline for each direction. You can use this baseline to compare with other OTDR
scan results.
Choose the scan file and baseline file, and click the Refresh icon next to the Port drop-down list.
You can view the traces chart having Loss (dB) plotted against Distance (Km). The baseline chart is plotted in blue color,
and the selected otdr scan chart is plotted in green color.
To zoom into the graph, press Shift key and drag the mouse pointer to select the portion of the graph.
Click Download to download the data file saved in the Standard OTDR Record (SOR) format.
The SOR file contains fiber trace data that are recorded by the OTDR instrument when testing an optical fiber.
Click the Export as SVG icon to download the traces file in SVG format.
Perform OTDR Scan
Use this task to perform the OTDR scan on a specific port.
Click the hamburger icon at the top-left of the page, and click Node Configuration.
Step 2
Click the OTDR tab.
Step 3
Click the Provisioning tab.
Step 4
Choose either Hybrid or Fast mode using the toggle button.
Step 5
Choose the port, you want to scan.
Step 6
Click Start to start scanning.
OTDR scan started message appears.
Step 7
Click Ok.
Step 8
Click Stop, when you want to stop scanning.
Step 9
Click Yes to confirm.
OTDR scan terminated message appears.
Step 10
Click Ok.
Note
In the fast mode, an alarm (OTDR-FAST-SCAN-IN-PROGRESS-TX or OTDR-FAST-SCAN-IN-PROGRESS-RX) gets triggered informing that
the scan is running in fast mode.
Automatic OTDR Scan
Automatic OTDR scan is started by checking the check box of the following parameters:
System Start-up, Fiber cut & Repair-When there is a fiber cut or after fiber repair, automatic OTDR scan is started. You can set a time delay for the OTDR scan
by choosing the Start Delay (Min) value.
Span Loss Increase-When the span loss increases above the threshold value, automatic OTDR scan is started. You can choose the Span Loss Increase Threshold (dB) value.
Excessive ORL from Span-When the ORL information is excessive, automatic OTDR scan is started.
OTDR Graph and Event Table
You can view the OTDR configurations in the graph. The Events in the graph are represented as following:
O - OPEN CONNECTOR
P - PASS THROUGH
F - FACE PLATE
You can also print and download the graph in JPEG and PNG formats. You can view the Event table below the graph with the following
parameters:
Event ID
Location (km)
Magnitude (dB)
Type
Expected Input Power
You to manage optical power on external devices while performing cross connection at the node level using expected input power.
You can configure the expected input power on the OTS interface of the add port of the passive device.
You can set the expected input power on the following passive units:
15216-MD-48-ODD
15216-MD-48-EVEN
15216-MD-40-ODD
15216-MD-40-EVEN
15216-EF-40-ODD
15216-EF-40-EVEN
NCS1K-MD-64-C
NCS2K-MF-M16LC-CV
NCS2K-MF-4X4-COFS
NCS2K-MF-MPO-8LC
NCS2K-MF-6AD-CFS
NCS2K-MF-10AD-CFS
Manage Expected Input Power
Use this task to add, modify, view, or delete expected input power on the node.
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