Table Of Contents

6-Port OC-3/STM-1 Packet over SONET Line Card Configuration

Software Support

Checking Hardware and Software Compatibility

Default Values

Interface Syntax

Configuring the Interface

Configuration Commands

Setting the Clock Source

Configuring Framing

Specifying SONET Overhead

Controlling the S1 SONET Overhead Byte

Controlling a Transmitted S1 Overhead Byte

Reacting to a Received S1 Overhead Byte

Configuring Packet over SONET SPE Scrambling

Configuring Loopback Testing

Configuring APS

6-Port OC-3/STM-1 Packet over SONET Line Card Configuration

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This chapter describes the procedures for configuring the Cisco 10000 series 6-Port OC-3/STM-1 Packet over SONET line card, hereafter known as the 6-Port OC-3/STM-1 Packet over SONET line card.

The 6-Port OC-3/STM-1 Packet over SONET line card provides 6 STS-3/STM-1 Packet over SONET trunk uplinks that support throughput of up to 155.52 Mbps each over a SONET/ITU-T Synchronous Digital Hierarchy (SDH) interface. Each port (0 to 5) has a single-mode optical fiber intermediate-reach LC connector.

This chapter contains the following sections:

•Software Support

•Default Values

•Interface Syntax

•Configuring the Interface

•Configuration Commands

Software Support

Table 12-1 shows the minimum Cisco IOS release on each release train that supports the 6-Port OC-3/STM-1 Packet over SONET line card.

Table 12-1 6-Port OC-3/STM-1 Packet over SONET Line Card Software Support 

Required PRE	Minimum Cisco IOS Releases
PRE1	Cisco IOS Release12.0(22)S and later releases of Cisco IOS Release12.0S
PRE2	Cisco IOS Release 12.0(20)ST and later releases of Cisco IOS 12.0ST Cisco IOS Release12.0(22)S and later releases of Cisco IOS Release12.0S Cisco IOS Release 12.2(8)BZ and later releases of Cisco IOS Release 12.2BZ Cisco IOS Release 12.3(7)XI and later releases of Cisco IOS 12.3XI Cisco IOS Release 12.2(28)SB and later releases of Cisco IOS 12.2SB

Checking Hardware and Software Compatibility

The PRE installed in the Cisco 10000 series router chassis must support the Cisco IOS software running on the router. Use the show version command to check the PRE version installed.

To see if a feature is supported by a Cisco IOS release, to locate the software document for that feature, or to check the minimum software requirements of Cisco IOS software with the hardware installed on your router, Cisco maintains the Software Advisor tool on Cisco.com at http://www.cisco.com/pcgi-bin/Support/CompNav/Index.pl

This tool does not verify whether line cards within a system are compatible, but does provide the minimum Cisco IOS requirements for individual hardware line cards, modules, or options.

You must be a registered user on Cisco.com to access this tool.

Default Values

Table 12-2 lists default values and command syntax for the 6-Port OC-3/STM-1 Packet over SONET line card. Table 12-2 includes the command to modify a default value, and indicates if a value needs to be the same (or opposite) on the remote end of the connection.

Table 12-2 6-Port OC-3/STM-1 Packet over SONET Line Card Defaults 

Command Name	Default Setting	Command Syntax	Remote Side Setting
bandwidth	155,000	bandwidth kilobits	Same.
clock source	line	clock source [line | internal]	At least one side must be set to internal.
crc	16	crc [16 | 32]	Same.
encapsulation	HDLC	encapsulation [hdlc | ppp]	Same.
keepalive	no keepalive	[no] keepalive period	Same.
loopback	no loopback	[no] loopback [line|internal]	Same
mtu (maximum transmission unit)	4470	mtu size	Same.
pos framing	SONET	pos framing [sonet | sdh]	Same.
pos scramble-atm	No scrambling	[no] pos scramble-atm	Same.
pos flag (SONET overhead)	c2—0xcf j0—0x01 s1s0—0	pos flag [c2 | j0 | s1s0] value	Same.

Interface Syntax

To specify an interface number in a configuration command, use the syntax in Table 12-3 to identify interfaces on the 6-Port OC-3/STM-1 Packet over SONET line card.

Table 12-3 6-Port OC-3/STM-1 Packet over SONET Line Card Interface Syntax

Type of Interface	Slot	Subslot	Port
Packet over SONET interface	1 to 8	0	0 to 5

The following example shows the syntax for configuring a 6-Port OC-3/STM-1 Packet over SONET line card in slot 1:

Router(config)# interface pos 1/0/0

Configuring the Interface

After you verify that the 6-Port OC-3/STM-1 Packet over SONET line card is installed correctly, use the following procedure to configure the new interface. Be prepared with the information you will need, such as the interface IP address.

Use the following procedure to create a basic configuration—enable an interface and specify IP routing.

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Step 1 At the global configuration prompt, specify the new interface to configure by entering the interface pos command and interface address. For example:

Router(config)# interface pos 1/0/1

Step 2 Assign an IP address and a subnet mask to the interface using the ip address configuration subcommand, as in the following example:

Router(config-if)# ip address 192.168.255.255 255.255.255.0 

Step 3 Specify either HDLC or PPP encapsulation. For example:

Router(config-if)# encapsulation hdlc

Step 4 If necessary, modify the 6-Port OC-3/STM-1 Packet over SONET line card configuration or that of the remote device to ensure that, where appropriate, they use the same settings. For more information, refer to the Remote Side Setting column in Table 12-2.

Step 5 Add any other configuration subcommands required for the enabling of routing protocols and adjust the interface characteristics.

Step 6 Enter the no shutdown command to enable the interface.

Router(config-if)# no shutdown

Step 7 When you have included all of the configuration subcommands to complete the configuration, enter Crtl-Z to exit configuration mode.

Step 8 Write the new configuration to memory.

Router# copy running-config startup-config

When the configuration has been stored, the system displays an OK message.

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After you have completed your configuration, you can check it using the show interface pos slot/subslot/port command.

Configuration Commands

The following sections present some of the commands that you can use to customize your 6-Port OC-3/STM-1 Packet over SONET line card configuration.

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Note These configuration commands are specific to each port on the 6-Port OC-3/STM-1 Packet over SONET line card.

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Setting the Clock Source

You can set the internal or line clock source by using the clock source command.

clock source {internal | line}

Where:

•internal specifies that the internal clock source is used

•line specifies that the network clock source is used

The default is clock source line.

In this example, the line card is instructed to use a line clock source.

Router(config)# interface pos 3/0/2

Router(config-if)# clock source line

Configuring Framing

You can use the pos framing command to set framing to SONET STS-3c or SDH STM-1 framing.

pos framing [sdh | sonet]

[no] pos framing

The default is SONET.

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Note Your system must support SDH to use this option.

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Use the no form of the command to restore the default framing mode.

In the following example, the framing type is set to SONET:

Router(config)# interface pos 5/0/1

Router(config-if)# no pos framing 

Specifying SONET Overhead

You can use the pos flag command to assign values for specific elements of the frame header. This command is typically used to meet a standards requirement or to ensure interoperability with another vendor's equipment.

pos flag [c2 value] [j0 value] [s1s0 value]

[no] pos flag [c2 value] [j0 value] [s1s0 value]

Where:

•c2 is a path signal identifier, and value is one of the following:

–0xCF for PPP or HDLC without scrambling

–0x16 for PPP or HDLC with scrambling

•j0 is the section trace byte, and value is 0x01 for interoperability with some SDH devices in Japan

•s1s0 is part of the payload pointer byte, and value is 0 for OC-3c and 2 for AU-4

Use the no form of the command to restore the default values.

In the following example, the c2 bit is set to 0xCF.

Router(config)# interface pos 4/0/02

Router(config-if)# pos flag c2 0xCF

Controlling the S1 SONET Overhead Byte

In most situations, the default value for the S1 SONET overhead byte (0x0) does not need to be changed. Refer to the SONET standards for information about the possible values for the S1 SONET overhead byte and the definition of each value.

Controlling a Transmitted S1 Overhead Byte

In Cisco IOS Release 12.2(28)SB, use the pos flag s1-byte tx command in interface configuration mode to control the transmission of the S1 SONET overhead byte.

pos flag s1-byte tx value

Where:

•value is in the range of 0x0 to 0xF

•0x0 is the default value

In the following example the S1 SONET overhead byte is set to 0xF:

pos flag s1-byte tx 0xF

Reacting to a Received S1 Overhead Byte

In Cisco IOS Release 12.2(28)SB, use the pos flag s1-byte rx-communicate command to direct the router to switch the clock source to internal when it receives an S1 SONET overhead byte with a value of 0xF. When the S1 SONET overhead byte changes from 0xF to any other value, the clock source reverts back to the clock source specified in the user configuration.

The S1 overhead byte is ignored by the receiving router unless the pos flag s1-byte rx-communicate command is issued.

pos flag s1-byte rx-communicate

no pos flag s1-byte rx-communicate

The following example directs the router to switch to internal clocking when it receives an S1 SONET overhead byte with a value of 0xF:

pos flag s1-byte rx-communicate

The default for the pos flag s1-byte rx-communicate command is disabled or off.

Configuring Packet over SONET SPE Scrambling

You can use the pos scramble-atm command to scramble the Packet over SONET synchronous payload envelope (SPE). SONET payload scrambling applies a self-synchronous scrambler to the SPE of the interface to ensure sufficient bit transition density.

pos scramble-atm

[no] pos scramble-atm

The default is no Packet over SONET SPE scrambling.

Use the no form of the command to disable scrambling.

In the following example, scrambling is enabled:

Router(config)# interface pos 3/0/3

Router(config-if)# pos scramble-atm

Configuring Loopback Testing

To enable loopback testing of data transmitted from the PRE line card to the 6-Port OC-3/STM-1 Packet over SONET line card and back, use the loopback command in interface configuration mode.

loopback [line | internal]

[no] loopback [line | internal]

Where:

•loopback line loops any data received at the 6-Port OC-3/STM-1 Packet over SONET line card network interface back into the network

•loopback internal loops any data sent out the 6-Port OC-3/STM-1 Packet over SONET line card back into the 6-Port OC-3/STM-1 Packet over SONET line card

Use the no form of the command to stop the loopback test.

For more information on loopbacks, refer to the online Cisco 10000 Series Internet Router Troubleshooting Guide.

In the following example, a loopback is set for the 6-Port OC-3/STM-1 Packet over SONET line card in slot 5:

Router(config)# interface pos 5/0/0

Router(config-if)# loopback line

Configuring APS

The 6-Port OC-3/STM-1 Packet over SONET line card supports port-level automatic protection switching (APS). For information about APS redundancy commands., see the Cisco 10000 Series Router Software Configuration Guide.