Forward Error Correction - cisco.com · Tip:WhenthenumberofrowsintheFECSettingstableexceedstheTSfoldersize,thetableisdividedin multipletablepages.Navigationtoolsarethendisplayedunderthetable

Forward Error Correction

This section outlines the FEC option of the GbE, GbE MK2, and 10GE card, including how to configure itssettings for incoming and outgoing transport streams.

• Introducing FEC, page 1

• Configuring the FEC Settings for Incoming Transport Streams, page 6

• Configuring the FEC Settings of Outgoing Transport Streams, page 12

Introducing FECDue to its nature (occasionally packet loss, packet reordering, and packet jittering), a traditional IP networkis not the perfect channel for sending broadcast-quality compressed video content. Forward error correction(FEC), developed by the PRO-MPEG forum, is a unique technology to enhance the robustness of video trafficover IP networks. The DCM supports Pro-MPEG Code of Practice (COP) #3 release2, which is based on theexclusive or (XOR) Boolean operator applied to several data packets. When a packet (called FEC packet) iscreated by performing the XOR Boolean operation on several RTP packets, a missing RTP packet can alwaysbe reconstructed by performing the XOR operation on the FEC packet and the remaining RTP packets.

FEC = RTP1 XOR RTP2

RTP1 = FEC XOR RTP2

RTP2 = FEC XOR RTP1

FEC ProfilesThe PRO-MPEG forum provides two FEC profiles: 1D FEC and 2D FEC, each havingmultiple FEC schemes.

• 1D FEC profile

The 1D FEC profile maps the RTP packet stream across columns (matrix of data packets). See thefollowing illustration.

Digital Content Manager (DCM) Configuration Guide - Software Version 21.10 OL-29584-20 1

TheXORBoolean operation is performed on the columnRTP packets. This approach provides robustnessagainst single missing RTP packets andmultiple consecutivemissing packets, as long as only one packetis missing in a column and the numbers of consecutive missing packets do not exceed the number ofcolumns (L).

Example:When data packets 9, 10, and 11 are missing at the receiver side, these packets can bereconstructed by the remaining column packets and FEC packet 1, 2, and 3.

In the example, a burst loss of maximum four consecutive data packets can be reconstructed.

• 2D FEC profile

Digital Content Manager (DCM) Configuration Guide - Software Version 21.102 OL-29584-20

Forward Error CorrectionFEC Profiles

The error protection can be enhanced by performing the XOR Boolean on both the column packets androw packets. As shown in the following illustration, a FEC packet is created for each row and for eachcolumn.

The 2D FEC scheme is able to reconstruct multiple missing packets in a single row and in a singlecolumn.

Example: In the following illustration, data packets 1, 7, 9, 10, 11, 12, and 13 are lost.


Forward Error CorrectionFEC Profiles

Data packet 1, 7, and 13 can be reconstructed by the remaining row packets and associated row FECpackets ('1, '2, and '4). Once data packets 1, 7, and 13 are reconstructed, data packets 9, 10, 11, and 12can be reconstructed by the associated column data packets and column FEC packets (1, 2, 3, and 4).

FEC SchemesThe FEC scheme is determined by the number of columns or row length (L) and the number of rows or columndepth (D). Pro-MPEG Code of Practice #3 specifies following limits:

• For 1D FEC profile:

L * D ≤ 1001 ≤ L ≤ 204 ≤ D ≤ 20

• For 2D FEC profile:

L * D ≤ 1004 ≤ L ≤ 204 ≤ D ≤ 20

• For Annex A (nonblock aligned sending arrangement):

L < D

Note • For outgoing TSs, the DCM allows using L x D ≤ 256.

• For incoming TSs, the DCM only accepts L x D 100. For TSs with L x D > 100, the FEC L/D Erroralarm is generated.

The following table shows the L and D limitation:


Forward Error CorrectionFEC Schemes

: For 1D FEC only

: For 1D FEC and 2D FEC

: Allowed by the DCM (for outgoing TSs) but not by Pro-MPEG Code of Practice #3

: Not allowed

FEC Packet TransportationThe column FEC and row FEC packets are sent using separate streams. The DCMGUI allows you to configurethe destination multicast IP address of the FEC streams and the UDP port numbers.

For Pro-MPEG Code of Practice (COP) #3 release2 compliant streams, the UDP port for the column FECstream is two higher than TS UDP port and the UDP port for the row FEC stream is four higher.

Important

Sending ArrangementsThe DCM implements both Pro-MPEG COP#3 release 2 Annex A and Annex B FEC packet sendingarrangement.

• Annex A (nonblock aligned sending arrangement)— Each FEC packet is sent L packets after the lastdata packet it pertains to.

• Annex B (block aligned sending arrangement)— Column FEC packets are sent by using an interleaver.

Overhead and LatenciesThe transmission overhead and the decoder latency, which is created by adding FEC packets, depend on theFEC profile (1D or 2D) and the FEC scheme. For instance, a 1D profile with a column depth of four rowsgenerates an overhead of 25 percent.

RequirementsForward error correction needs a GbE card with FEC option, a GbE MK2, or a 10GE card. In theConfiguration, Inputs, and Outputs tree, the presence of a FEC card on a GbE card is indicated in the cardbranch.

The FEC option of the DCM is on a per license basis. Each incoming TS, preconfigured incoming TS, andoutgoing TS for which FEC error protection is enabled and each incoming TS for which packet reordering isenabled, needs one FEC license key. For more information about licenses, see Licensing.

Restrictions• The FEC error protection feature cannot be used for incoming VBR RTP streams.


Forward Error CorrectionFEC Packet Transportation

b_DCM_config_guide_chapter_01.pdf#unique_13

• If hitless merge is enabled, FEC error protection for incoming RTP streams cannot be enabled. SeeConfiguring the Hitless Merge Settings of a Card. Overruling destination IP addresses of outgoing TSscannot be combined with FEC encoding on the same card.

• FEC encoding and decoding, and packet reordering using a 10GE card is only possible on streams withseven MPEG packets per RTP packet.

Configuring the FEC Settings for Incoming Transport StreamsBefore the DCM is able to reconstruct an incoming TS with packets from the incoming FEC streams, the FECstreams must be assigned to the corresponding TS. Since the IP address / UDP port identify the incomingFEC streams, the IP address and UDP port parameters, which must be entered in the GUI during theconfiguration process, must match the IP address/UDP port of the incoming FEC streams. If the entered IPaddress/UDP port combination does not match with an incoming FEC stream or the FEC mode does notcorrespond with the FEC profile of the incoming streams, it is not indicated in the GUI after applying thesettings but theMissing FEC streams alarm is generated.

Configuring the FEC Settings of a Single Incoming Transport Stream

Procedure

Step 1 In the DCM GUI, choose Service > Tree View from the main menu.The Tree View page appears.

Step 2 In the Inputs tree, double-click the TS for which FEC settings must be configured.The Input TS Settings page appears.

Step 3 Refer to the TS FEC table.Step 4 From theMode drop-down list, choose one of the following error protection profiles:

• Disabled— The error protection is disabled.

• FEC 1D— The 1D FEC profile is used.


• Packet Reordering— Only RTP packet reordering without FEC is done.

• Default (xxxxxxxx)— The default value is used. The configured default value is shown betweenbrackets.

Step 5 Perform the following steps for the column FEC stream:a) In the Column FEC Stream IP field, enter the multicast destination IP address of the incoming column

FEC stream. For an incoming stream with a unicast destination IP address, leave this field empty or enter0.0.0.0.

b) In the corresponding UDP field, enter the UDP port number of this incoming column FEC stream.

Step 6 In case of FEC 2D profile, perform the following steps for the row FEC stream:


Forward Error CorrectionConfiguring the FEC Settings for Incoming Transport Streams


a) In the Row FEC Stream IP field, enter the multicast destination IP address of the incoming row FECstream. For an incoming streamwith a unicast destination IP address, leave this field empty or enter 0.0.0.0.

b) In the corresponding UDP field, enter the UDP port number of this incoming row FEC stream.

Step 7 Click Apply.

Tip •When the FEC parameters are configured properly, the L, D, FEC overhead, and latency appear inthe TS FEC table.

• The arrow in the Statistics column can be used to open the TS_FEC_Statistics dialog box. Formore information about FEC statistics, see Checking the FEC Statistics, on page 11.

Configuring the FEC Settings of Multiple Incoming Transport Streams of aPort/TS Folder

Procedure


Step 2 In the Inputs tree, double-click the port or TS folder with the TSs for which FEC settings must be configured.The Input Port TS Settings page appears.

Step 3 Click the TS FEC tab.The Input Port TS FEC page appears.

Step 4 In the FEC Settings table, double-click the TS for which FEC settings must be configured.The row becomes editable.

Step 5 From theMode drop-down list of the corresponding TS, choose one of the following error protection profiles:


• FEC 1D— The 1D column FEC profile is used.



• Default (xxxxxxxx)— The default value is used. The configured default value is shown betweenbrackets.


Forward Error CorrectionConfiguring the FEC Settings of Multiple Incoming Transport Streams of a Port/TS Folder

Step 6 Perform the following steps for the column FEC stream:a) In theColumn FEC Stream - IP Address field, enter the multicast destination IP address of the incoming

column FEC stream. For an incoming stream with a unicast destination IP address, leave this field emptyor enter 0.0.0.0.

b) In the correspondingColumn FEC Stream - UDPPort field, enter the UDP port number of this incomingcolumn FEC stream.

The Column FEC Stream settings are only applicable when theMode parameter is set to FEC 1D or FEC2D.

Step 7 In case of FEC 2D profile, perform the following steps for the row FEC stream:a) In the Row FEC Stream - IP Address field, enter the multicast destination IP address of the incoming

row FEC stream. For an incoming stream with a unicast destination IP address, leave this field empty orenter 0.0.0.0.

b) In the corresponding Row FEC Stream - UDP Port field, enter the UDP port number of this incomingrow FEC stream.

The Row FEC Stream settings are only applicable when theMode parameter is set to FEC 2D.

Step 8 Click Apply All.

Tip •When the FEC parameters of an incoming TS are properly configured, the L, D, FEC, and latencyoverhead appears in the FEC Settings table.

• The arrow in the Statistics column of an incoming TS can be used to open the TS_FEC_Statisticsdialog box. For more information about FEC statistics, see Checking the FEC Statistics, on page11.

Changing the FEC Settings of Incoming Transport Streams Using the UpdateTS Settings Function

When FEC settings for several TSs on a port must be changed to similar values, the update TS settings functioncan be used.

Procedure


Step 2 In the Inputs tree, double-click the port with the TSs for which FEC settings must be configured.The Input Port TS Settings page appears.


Step 4 In the FEC Settings table, select the rows of the TSs for which settings must be changed.


Forward Error CorrectionChanging the FEC Settings of Incoming Transport Streams Using the Update TS Settings Function

Tip: When the number of rows in the FEC Settings table exceeds the TS folder size, the table is divided inmultiple table pages. Navigation tools are then displayed under the table. Rows can only be selected in thetable page that is displayed. For more information, see About Tables.

Step 5 Refer to the Update TS Settings area.Step 6 In the Update TS Settings area, choose the desired value from the drop-down list of the parameter that must

be changed for all selected TSs.Step 7 Click Update All Selected. The settings are changed in the FEC Settings table.Step 8 Click Apply.

Preconfiguring Incoming Transport Streams with FEC SettingsParticular FEC settings of TSs, which are not yet at the input of the DCM, can be preconfigured.

Procedure


Step 2 In the Inputs tree, double-click the port for which a TS must be preconfigured.The Input Port TS Settings page appears.


Step 4 Refer to the Add Preconfigured TS area.Step 5 In the Source IP field, enter the source IP address of the incoming stream. This parameter is only available

if the Input Stream Creation Mode of this card is set to Source IP - IP:UDP.Step 6 In the IP Address field, enter the multicast destination IP address of the incoming stream. For an incoming

stream with a unicast destination IP address, leave this field empty or enter 0.0.0.0.Step 7 In the UDP Port field, enter the UDP port number of this incoming stream.Step 8 From theMode drop-down list, choose one of the following values:





Step 9 From the FEC Streams drop-down list, choose one of the following values:

• Same IP and UDP+2, UDP+4— The FEC streams have the destination IP address of the incomingTS. The destination UDP port of the column FEC stream is the UDP port number of the TS increasedby two and the destination UDP port number of the row FEC stream (2D FEC profile only) is this UDPport number increased by four.


Forward Error CorrectionPreconfiguring Incoming Transport Streams with FEC Settings


• Same UDP and IP+1, IP+2— The FEC streams have the destination UDP port of the incoming TS.The destination IP address of the column FEC stream is the TS IP address increased by one and thedestination IP address the row FEC stream (2D FEC profile only) the TS IP address increased by two.

• Custom Setting— The settings for the column and row FEC streams are configurable.

Step 10 Perform the following steps if the FEC Streams parameter is set to Custom Setting.a) In the Column IP field, enter the multicast destination IP address of the incoming column FEC stream.

For an incoming stream with a unicast destination IP address, leave this field empty or enter 0.0.0.0.b) In the Column UDP field, enter the UDP port number of this incoming column FEC stream.c) In the Row IP field, enter the multicast destination IP address of the incoming row FEC stream. For an

incoming stream with a unicast destination IP address, leave this field empty or enter 0.0.0.0.d) In the Row UDP field, enter the UDP port number of this incoming row FEC stream.The Row IP and Row UDP fields are only applicable when theMode parameter is set to FEC 2D.

Step 11 Click Add Row.The preconfigured TS is added to the FEC Settings table.

Note • Preconfigured TSs with FEC settings for which theMode is set to FEC 1D, FEC 2D, or PacketReordering can only be done when free FEC licenses are available. For more information aboutlicenses, see Licensing.

• In the FEC Settings table, preconfigured TSs with configured FEC settings can be removed bychecking the check box of the corresponding preconfigured TS and clicking Remove CheckedItems.

Changing the Default FEC Settings of Incoming Transport StreamsThe following procedure describes how to change the default FEC parameter values for incoming TSs. Thesevalues are used for each incoming TS for which the associated parameters are set to default.

Changing the default value involves changing the associated parameter for all incoming TS for which thevalue is set to default.

Important

Procedure

Step 1 In the DCM GUI, choose Configuration from the main menu.


Forward Error CorrectionChanging the Default FEC Settings of Incoming Transport Streams


The System Settings page appears.

Step 2 In the Configuration tree, double-click the interface card for which default FEC parameters for incomingTSs must be changed. The interface configuration page of the selected interface card is displayed.

Step 3 Choose Default Settings and click the Input TS tab.Step 4 Refer to the Default Input FEC Settings area.Step 5 From theMode drop-down list, choose one of the following error protection profiles:




• Packet Reordering— Only RTP packet reordering without forward error correction is done.

Step 6 From the FEC Stream drop-down list, choose one of the following values:

• Same IP and UDP+2, UDP+4— The FEC streams have the destination IP address of the incomingTS. The destination UDP port of the column FEC stream is the UDP port number of TS increased bytwo and the destination UDP port number of the row FEC stream (2D FEC profile only) the TS UDPport increased by four.

• Same UDP and IP+2, IP+4— The FEC streams have the destination UDP port of the incoming TS.The destination IP address of the column FEC stream is the TS IP address increased by two and thedestination IP address the row FEC stream (2D FEC profile only) the TS IP address increased by four.

The FEC Stream drop-down list is only applicable if the FEC 1D or FEC 2D profile is chosen.


Checking the FEC StatisticsThe following steps describe how to check the FEC statistics for a particular incoming TS.

Procedure

Step 1 In the DCM GUI, choose Service > Tree View from the main menu.Step 2 In the Inputs tree, double-click the TSs for which FEC statistics must be checked.

The Input TS Settings page appears.

Step 3 In the TS FEC table, click the arrow in the Statistics column.A dialog box appears with the TS FEC statistics of the corresponding TS.

The following RTP statistics of incoming RTP streams are available.

• Valid Packets— The number of IP packets received by the DCM for the TS.

•Missing Packets Before Error Correction (on Main)— The number of missing IP packets beforeerror correction.


Forward Error CorrectionChecking the FEC Statistics

•Missing Packets Before Error Correction (on HM Backup)— Unused.

•Missing Packets After Error Correction— The number of missing IP packets after error correction.

• Fixed Packets— The number of IP packets reconstructed by the DCM for the TS.

• Duplicated Packets— The number of duplicated IP packets of the TS.

• Reordered Packets— The number of IP packets reordered by the DCM for the TS.

• Packets Out of Range— The number of frames that cannot be stored to the FEC decoding buffer (RTPsequence number falls outside the buffer).

• PCR Up Time— The time expressed in seconds since PCR selection or the last PCR discontinuity.

Tip • The TS FEC statistics can be restarted by clicking Reset.

• To guard the incoming RTP stream, you can set thresholds. If a particular threshold is exceeded, analarm is generated. For more information, see Configuring RTP Stream Alarms.

• After loading the statistics from the DCM, the statistic figures are automatically refreshed at regulartime. For some reasons, it can be useful to switch off these automatically refresh actions or to useanother refresh rate. Therefore, this dialog box is provided with a refresh ( ) drop-down list thatcan be used to change the refresh rate (every 10 sec, every 30 sec, or every minute) or to switch offthese refresh actions. The default value of these refresh actions can be changed as describes inChanging the Tree Settings.

Configuring the FEC Settings of Outgoing Transport Streams

Configuring the FEC Settings of a Single Outgoing Transport Stream

During the outgoing TS creation process, certain FEC settings are automatically configured with defaultvalues. To facilitate the configuration of outgoing TSs, other values can be configured to these defaults.To change these default values, see Changing the Default FEC Settings of Outgoing Transport Streams,on page 15.

Tip

Procedure


Step 2 In the Outputs tree, double-click the TSs for which FEC settings must be configured.


Forward Error CorrectionConfiguring the FEC Settings of Outgoing Transport Streams



The Output TS page appears.

Step 3 Click the Advanced tab.Step 4 Refer to the FEC Settings area.Step 5 From theMode drop-down list, choose one of the following settings:

• Disabled— Forward error correction is disabled.



When the Output Protocol parameter of the TS is set to UDP and theMode parameter is set to FEC 1D orFEC 2D, a dialog box is displayed to change the protocol to RTP. Click OK.

Tip: If the destination IP address of the TS on the mirroring port is overruled, theMode parameter cannot bechanged to FEC 1D or FEC 2D. See Overruling the Destination IP Address of an Outgoing Transport Stream.

Step 6 From the Sending Arrangement drop-down list, choose Block aligned or Non block aligned.Step 7 Enter the destination IP address for the column FEC stream in the Column FEC Stream IP field and the

destination UDP port number in the corresponding UDP field. If theMode parameter is set to Disabled, theColumn FEC Stream IP and UDP fields are dimmed.

Step 8 Enter the destination IP address for the row FEC stream in the Row FEC Stream IP field and the destinationUDP port number in the corresponding UDP field. The Row FEC Stream IP and UDP fields are onlyapplicable if theMode parameter is set to FEC 2D.

Step 9 To determine the FEC scheme, enter the number of columns in the L field and the column depth (number ofrows) in the D field. If theMode parameter is set to Disabled, the L and D fields are dimmed.


Changing the FEC Settings of Multiple Outgoing Transport Streams of a Port/TSFolder

Procedure


Step 2 In the Outputs tree, double-click the port with the TSs for which FEC settings must be configured.The Output Port TS page of the selected port appears.

Step 3 Click the TS FEC tab. The Output Port FEC page appears.Step 4 In the FEC Settings table, double-click the TS for which FEC settings must be configured.

The row becomes editable.


Forward Error CorrectionChanging the FEC Settings of Multiple Outgoing Transport Streams of a Port/TS Folder


Step 5 From theMode drop-down list, choose one of the following settings:




If the destination IP address of the TS on the mirroring port is overruled, theMode parameter cannot bechanged to FEC 1D or to FEC 2D. See Overruling the Destination IP Address of an Outgoing TransportStream.

Step 6 From the Sending Arrangement drop-down list, choose Block aligned or Non block aligned.Step 7 Enter the destination IP address for the column FEC stream in the Column FEC Stream IP field and the

destination UDP port number in the corresponding UDP field. If theMode parameter is set to Disabled, theColumn FEC Stream IP and UDP fields are dimmed.

Step 8 Enter the destination IP address for the row FEC stream in the Row FEC Stream IP field and the destinationUDP port number in the corresponding UDP field. The Row FEC Stream IP and UDP fields are onlyapplicable if theMode parameter is set to FEC 2D.

Step 9 To determine the FEC scheme, enter the number of columns in the L field and the column depth (number ofrows) in the D field. If theMode parameter is set to Disabled, the L and D fields are dimmed.

Step 10 Click Apply.

When the Output Protocol parameter of the TS is set to UDP and theMode parameter is set to FEC 1D orFEC 2D, the Protocol column is added to the table that can be used to change the protocol to RTP.

Changing the FEC Settings of Outgoing Transport Streams Using the UpdateTS Settings Function

When particular FEC parameters for all TSs on a port must be changed to similar values, the update all TSfunction can be used.

Procedure


Step 2 In the Outputs tree, double-click the port with the TSs for which FEC settings must be configured.The Output Port TS page appears.

Step 3 Click the TS FEC tab.


Forward Error CorrectionChanging the FEC Settings of Outgoing Transport Streams Using the Update TS Settings Function



The Output Port FEC page appears.

Step 4 In the FEC Settings table, select the rows of the TSs for which settings must be changed.Note: When the number of rows in the FEC Settings table exceeds the TS folder size, the table is divided inmultiple table pages. Navigation tools are then displayed under the table. Rows can only be selected in thetable page that is displayed. For more information, see About Tables.

Tip: Changing theMode to FEC 1D or FEC 2D is only possible when the Output Protocol parameter ofthe TSs is set to RTP.

Step 5 Click Update All Selected.The settings are changed for all selected rows in the FEC Settings table.

Step 6 Click Apply.

Changing the Default FEC Settings of Outgoing Transport StreamsDuring the outgoing TS creation process, particular FEC parameters are configured with default values. Tofacilitate the configuration, these default values can be changed.

Procedure

Step 1 In the DCM GUI, choose Configuration from the main menu.The System Settings page appears.

Step 2 In theConfiguration tree, double-click the GbE or GbEMK2 card for which the default FEC parameter mustbe changed.The interface configuration page of the selected card appears.

Step 3 Choose Default Settings and then click the Output TS tab.Step 4 Refer to the Default Output FEC Settings.Step 5 From theMode drop-down list, choose one of the following values:




Step 6 From the Sending Arrangement drop-down list, choose Block aligned or Non block aligned.Step 7 From the FEC Streams drop-down list, choose one of the following values.

• Same IP and UDP+2, UDP+4— If a new TS is created, the FEC streams get the IP address of the TS.The column FEC stream gets the TS UDP port increased by two and the row FEC stream (2D FECprofile only) gets the TS UDP port increased by four.

• Same UDP and IP+1, IP+2— If a new TS is created, the FEC streams get the UDP port of the TS.The column FEC stream gets the TS IP address increased by one and the row FEC stream (2D FECprofile only) gets the TS IP address increased by two.


Forward Error CorrectionChanging the Default FEC Settings of Outgoing Transport Streams


Step 8 Enter the number of columns in theL field and the column depth (number of rows) in theD field for determiningthe FEC scheme. The L and D fields are dimmed if theMode parameter is set to Disabled.

Step 9 Click Apply.

Generating FEC ErrorsFor test purposes, the DCM is able to generate FEC errors for a particular TS by dropping IP packets. FECerrors can be created for a single burst cycle or can be generated continuously. A single burst cycle consistsof several dropped packets (bad packets) after sending several good packets.

Procedure

Step 1 Log on to the DCM using a GUI account belonging to the Administrators security group and choose Service> Tree View from the main menu.The Tree View page appears.

Step 2 In the Outputs tree, double-click the port with the TS for which FEC errors must be generated.The Output Port TS page of the selected port appears.

Step 3 Click the TS FEC tab.The Output Port FEC page appears.

Step 4 Refer to the FEC Error Generation area.Step 5 From theMode drop-down list, choose one of the following items:

• Disabled— The FEC error generating process is disabled.

• Single burst— The single FEC error burst is executed.

• Continuous— The continuous FEC error generation process is enabled.

Step 6 In the Good Packets field, enter the number of good packets that must be sent before packets are dropped.Step 7 In the Bad Packets field, enter the number of packets that must be dropped during one burst cycle.Step 8 Enter the destination IP address of the TS in the TS IP field and the UDP port number in the UDP field.Step 9 Click Set.

The FEC error generating process is started.

When applying new error generation settings, the previous error condition is cleared automatically.

Tip • The FEC Error generation process can be stopped by clicking Stop.

• The continuous FEC error generating process can be stopped by changing theMode to Disabledand clicking Set.

• In the FEC Settings table, indicates a TS for which FEC Error generation is active.


Forward Error CorrectionGenerating FEC Errors

Note • A reboot of the DCM clears the current error generation settings.

• For a GbE card, media and column/row packets are taken into account for good and bad packets.For a GbE MK2 and 10GE card, only media packets are taken into account.





Documents

Forward Error Correction - cisco.com · Tip:WhenthenumberofrowsintheFECSettingstableexceedstheTSfoldersize,thetableisdividedin multipletablepages.Navigationtoolsarethendisplayedunderthetable