Table Of Contents

Packet-over-SONET/SDH Interface Commands on Cisco IOS XR Software

crc (POS)

encapsulation hdlc (POS)

encapsulation ppp

interface pos

keepalive (POS)

pos

ppp authentication

ppp chap password

ppp chap refuse

ppp max-bad-auth

ppp max-configure

ppp max-failure

ppp max-terminate

ppp ms-chap password

ppp ms-chap refuse

ppp pap refuse

ppp pap sent-username password

ppp timeout authentication

ppp timeout retry

show interfaces pos

show ppp interfaces

transmit-delay

Packet-over-SONET/SDH Interface Commands on Cisco IOS XR Software

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This module describes the Cisco IOS XR commands used to configure, monitor, and troubleshoot Packet-over-SONET/SDH (POS).

POS provides a method for efficiently carrying data packets in SONET or Synchronous Digital Hierarchy (SDH) frames. High-bandwidth capacity and efficient link utilization are characteristics that make POS largely preferred for building the core of data networks. POS uses PPP in High-Level Data Link Control (HDLC)-like framing for data encapsulation at Layer 2 (data link) of the Open System Interconnection (OSI) stack. This method provides efficient packet delineation and error control.

In addition to high-bandwidth efficiency, POS offers secure and reliable transmission for data. Reliable data transfer depends on timing integrity.

The real-time POS functionality is performed in hardware, according to the hardware configuration setup. Configured hardware events are detected by the framer application-specific integrated circuits (ASICs) and the control is passed to the software. The generic POS driver is responsible for providing a mechanism to configure the hardware on a per-interface basis, to handle interface state transitions, and to collect POS-related statistics.

This module includes the Cisco High-Level Data Link Control (cHDLC), Serial Line Address Resolution Protocol (SLARP), and PPP commands for POS interfaces.

cHDLC is a Cisco version of standard HDLC encapsulation, a bit-oriented synchronous data link layer protocol. HDLC specifies a data encapsulation method on synchronous serial links using frame characters and checksums. cHDLC also provides a simple control protocol called SLARP, which is used to maintain serial link keepalives.

PPP is an encapsulation scheme that can be used to send data over synchronous serial links. PPP also provides a Link Control Protocol (LCP) for negotiating properties of the link. LCP uses echo requests and responses to monitor the continuing availability of the link. PPP provides the following Network Control Protocols (NCPs) for negotiating properties of data protocols that will run on the link:

•Cisco Discovery Protocol Control Protocol (CDPCP) to negotiate CDP properties

•IP Control Protocol (IPCP) to negotiate IP properties

•IP Version 6 Control Protocol (IPv6CP) to negotiate IPv6 properties

•Multiprotocol Label Switching Control Protocol (MPLSCP) to negotiate MPLS properties

•Open System Interconnection Control Protocol (OSICP) to negotiate OSI properties

crc (POS)

To set the length of the cyclic redundancy check (CRC) on a Packet-over-SONET/SDH (POS) interface, use the crc command in POS configuration mode. To return the CRC setting on a POS interface to the 32-bit default setting, use the no form of this command.

crc {16 | 32}

no crc {16 | 32}

Syntax Description

16	Sets 16-bit CRC mode.
32	Sets 32-bit CRC mode. The default is 32 bits.

Defaults

The default CRC mode is 32 bits.

Command Modes

POS configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

CRC is an error-checking technique that uses a calculated numeric value to detect errors in transmitted data. The designators 16 and 32 indicate the length (in bits) of the frame check sequence (FCS). A CRC of 32 bits provides more powerful error detection, but adds overhead. Both the sender and receiver must use the same setting.

CRC-16, the most widely used error checking method throughout the United States and Europe, is used extensively with WANs. CRC-32 is specified by IEEE standard 802 and as an option by some point-to-point transmission standards. It is often used on Switched Multimegabit Data Service (SMDS) networks and LANs.

Task ID

Task ID	Operations
pos-dpt	read, write

Examples

In the following example, the 32-bit CRC on POS interface 0/1/0/2 is enabled:

RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/2

RP/0/RP0/CPU0:router(config-if)# POS

RP/0/RP0/CPU0:router(config-if-pos)# crc 32

Related Commands

Command	Description
transmit-delay	Specifies a number of flag sequences to be inserted between the packets.

encapsulation hdlc (POS)

To set the Layer 2 encapsulation of an interface, use the encapsulation hdlc command in interface configuration mode. To restore the system to the default encapsulation, use the no form of this command.

encapsulation hdlc

no encapsulation

Syntax Description

This command has no arguments or keywords.

Defaults

For Packet-over-SONET/SDH (POS) interfaces, the default encapsulation is HDLC.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Use the encapsulation hdlc command to configure HDLC encapsulation on an interface. Some interfaces do not support any encapsulation other than the default encapsulation, in which case this command is not available.

Task ID

Task ID	Operations
hdlc	read, write
interface	read, write

Examples

In the following example, HDLC serial encapsulation is set on POS interface 0/3/0/1:

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation hdlc

Related Commands

Command	Description
show interface	Displays statistics for all interfaces configured on the router.

encapsulation ppp

To enable encapsulation for communication with routers or bridges using the PPP, use the encapsulation ppp command in interface configuration mode. To disable PPP encapsulation, use the no form of this command.

encapsulation ppp

no encapsulation ppp

Syntax Description

This command has no arguments or keywords.

Defaults

PPP encapsulation is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Use the encapsulation ppp command to enable PPP encapsulation on an interface.

Task ID

Task ID	Operations
ppp	read, write
interface	read, write

Examples

The following example shows how to set up PPP encapsulation on interface POS 0/1/0/1:

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

Related Commands

Command	Description
show ppp interfaces	Displays PPP state information for an interface.

interface pos

To enter interface configuration mode for a POS interface, use the interface pos command in global configuration mode. To delete a POS configuration, use the no form of this command.

interface POS instance

no interface POS instance

Syntax Description

instance

Either a physical interface instance or a virtual interface instance: •Physical interface instance. Naming notation is rack/slot/module/port, and a slash between values is required as part of the notation. –rack—Chassis number of the rack. –slot—Physical slot number of the card. –module—Module number. A physical layer interface module (PLIM) is always 0. –port—Physical port number of the interface. •Virtual interface instance. Range of numbers varies depending on interface type. For more information about the syntax for the router, use the question mark (?) online help function.

Defaults

No default behavior or values

Command Modes

Global configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enter interface configuration mode for a POS interface:

RP/0/RP0/CPU0:router(config)# interface pos 0/1/0/0

RP/0/RP0/CPU0:router(config-if)#

Related Commands

Command	Description
show interfaces pos	Displays information about a POS interface.

keepalive (POS)

To set the keepalive timer for a specific interface, use the keepalive command in interface configuration mode. To reset the keepalive timer to the default of 10 seconds, use the no form of this command.

keepalive {seconds | disable}

no keepalive

Syntax Description

seconds	Number of seconds that define the keepalive interval. Range is from 0 through 32767seconds. Default is 10 seconds.
disable	Turns off the keepalive timer.

Defaults

seconds = 10 seconds

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

cHDLC keepalives require that the keepalive command is configured the same way on both routers. The two connected routers have no way of negotiating the keepalive value, because there is no way for the routers to tell each other what their configured values are. The keepalive value configured on each router (local and partner) sets the rate at which the Cisco IOS XR software sends packets. It also sets the rate at which the local end expects to receive incoming packets.

To set the keepalive value to the default value, use the keepalive command without specifying a value for the seconds argument.

If three keepalives are sent to the peer and no response is received from the peer, then the link makes the transition to the down state.

Task ID

Task ID	Operations
hdlc	read, write

Examples

The following example shows how to configure keepalives for 3 seconds on POS interface 0/7/0/1:

RP/0/RP0/CPU0:router(config)# interface POS 0/7/0/1

RP/0/RP0/CPU0:router(config-if)# keepalive 3

pos

To access the POS configuration submode, use the pos command in interface configuration mode.

pos

Syntax Description

This command has no arguments or keywords.

Defaults

No default behavior or values

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

When you issue the pos command in interface configuration mode for a POS interface, the CLI prompt changes to "config-if-pos," indicating that you have entered POS configuration submode. In the following sample output, the question mark (?) online help function displays all the commands available under POS configuration submode:

RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/2

RP/0/RP0/CPU0:router(config-if)# POS

RP/0/RP0/CPU0:router(config-if-pos)# ?

  commit          Commit the configuration changes to running

  crc             Set the CRC on a POS interface

  describe        Describe a command without taking real actions

  do              Run an exec command

  exit            Exit from this submode

  no              Negate a command or set its defaults

  show            Show contents of configuration

transmit-delay Set POS transmit delay on an interface

Task ID

Task ID	Operations
pos-dpt	read, write

Examples

The following example shows how to access the POS configuration submode from the POS configuration mode:

RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/2

RP/0/RP0/CPU0:router(config-if)# POS

RP/0/RP0/CPU0:router(config-if-pos)# 

Related Commands

Command	Description
crc (POS)	Sets the length of the CRC on a POS interface.
transmit-delay	Specifies a number of flag sequences to be inserted between the packets.

ppp authentication

To enable Challenge Handshake Authentication Protocol (CHAP), MS-CHAP, or Password Authentication Protocol (PAP), and to specify the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface, use the ppp authentication command in interface configuration mode. To disable PPP authentication, use the no form of this command.

ppp authentication protocol [protocol [protocol]] [list-name | default]

no ppp authentication

Syntax Description

protocol	Name of the IP protocol used for PPP authentication. See Table 73 for the appropriate keyword. You may select one, two, or all three protocols, in any order.
list-name	(Optional) Used with authentication, authorization, and accounting (AAA). Name of a list of methods of authentication to use. If no list name is specified, the system uses the default. The list is created with the aaa authentication ppp command.
default	(Optional) Specifies the name of the list of methods created with the aaa authentication ppp command.

Defaults

PPP authentication is not enabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router. This command was corrected to include the possibility of specifying three protocols simultaneously.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

When you enable CHAP or PAP authentication (or both), the local router requires the remote device to prove its identity before allowing data traffic to flow. PAP authentication requires the remote device to send a name and a password, which is checked against a matching entry in the local username database or in the remote security server database. CHAP authentication sends a challenge message to the remote device. The remote device encrypts the challenge value with a shared secret and returns the encrypted value and its name to the local router in a response message. The local router attempts to match the remote device's name with an associated secret stored in the local username or remote security server database; it uses the stored secret to encrypt the original challenge and verify that the encrypted values match.

You can enable CHAP, MS-CHAP, or PAP in any order. If you enable all three methods, the first method specified is requested during link negotiation. If the peer suggests using the second method, or refuses the first method, the second method is tried. Some remote devices support only one method. Base the order in which you specify methods on the remote device's ability to correctly negotiate the appropriate method, and on the level of data line security you require. PAP usernames and passwords are sent as clear text strings, which can be intercepted and reused.

---

Note If you use a list-name value that was not configured with the aaa authentication ppp command, then PPP is disabled on the interface.

---

Table 73 lists the protocols used to negotiate PPP authentication.

Table 73 PPP Authentication Protocols for Negotiation

Protocol	Description
chap	Enables CHAP on a POS interface.
ms-chap	Enables Microsoft's version of CHAP (MS-CHAP) on a POS interface.
pap	Enables PAP on a POS interface.

Enabling or disabling PPP authentication does not affect the ability of the local router to authenticate itself to the remote device.

MS-CHAP is the Microsoft version of CHAP. Like the standard version of CHAP, MS-CHAP is used for PPP authentication. In this case, authentication occurs between a personal computer using Microsoft Windows NT or Microsoft Windows 95 and a Cisco router or access server acting as a network access server.

Enabling or disabling PPP authentication does not affect the local router authenticating itself to the remote device.

Task ID

Task ID	Operations
ppp	read, write
aaa	read, write

Examples

In the following example, CHAP is enabled on POS 0/4/0/1 and uses the authentication list MIS-access:

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/4/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp authentication chap MIS-access

Related Commands

Command	Description
aaa authentication ppp	Specifies one or more AAA authentication methods for use on serial interfaces running PPP.
encapsulation	Sets the encapsulation method used by the interface.
username	Configures a new user with a username, establishes a password, and grants permissions for the user.

ppp chap password

To enable a router calling a collection of routers to configure a common Challenge Handshake Authentication Protocol (CHAP) or MS-CHAP secret password, use the ppp chap password command in interface configuration mode. To disable the password, use the no form of this command.

ppp chap password [clear | encrypted] password

no ppp chap password [clear | encrypted] password

Syntax Description

clear	(Optional) Specifies the cleartext encryption parameter for the password.
encrypted	(Optional) Indicates that the password is already encrypted.
password	Cleartext or already-encrypted password.

Defaults

The password is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp chap password command is used for remote CHAP authentication only (when routers authenticate to the peer) and does not affect local CHAP authentication. This command is useful for routers that do not support this command (such as routers running older Cisco IOS XR software images).

The CHAP or MS-CHAP secret password is used by the routers in response to challenges from an unknown peer.

Task ID

Task ID	Operations
ppp	read, write
aaa	read, write

Examples

In the following example, a password (xxxx) is entered as a cleartext password:

RP/0/RP0/CPU0:router(config-if)# ppp chap password xxxx

When the password is displayed (as shown in the following example, using the show running-config command), the password xxxx appears as 7 151419090:

RP/0/RP0/CPU0:router(config)# show running-config interface POS 1/0/1/0

 ipv4 address 10.0.0.2 255.255.255.0

 encapsulation ppp

 ppp chap password 7 151419090

shutdown

On subsequent logins, entering any of the three following commands would have the same effect of making xxxx the password for remote CHAP authentication:

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 1/0/1/0

RP/0/RP0/CPU0:router(config-if)# ppp chap password xxxx

RP/0/RP0/CPU0:router(config-if)# ppp chap password 0 xxxx

RP/0/RP0/CPU0:router(config-if)# ppp chap password 7 1514190900

Related Commands

Command	Description
aaa authentication ppp	Specifies one or more authentication, authorization, and accounting (AAA) methods for use on serial interfaces running PPP.
ppp authentication	Enables CHAP, MS-CHAP, or PAP, and specifies the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface.
ppp chap refuse	Refuses CHAP authentication from peers requesting it.
ppp max-bad-auth	Configures a PPP interface not to reset itself immediately after an authentication failure but instead to allow a specified number of authentication retries.
show running-config	Displays the contents of the currently running configuration file or the configuration for a specific interface, or map class information.

ppp chap refuse

To refuse Challenge Handshake Authentication Protocol (CHAP) and MS-CHAP authentication from peers requesting it, use the ppp chap refuse command in interface configuration mode. To allow CHAP and MS-CHAP authentication, use the no form of this command.

ppp chap refuse

no ppp chap refuse

Syntax Description

This command has no arguments or keywords.

Defaults

CHAP and MS-CHAP authentication is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp chap refuse command specifies that CHAP and MS-CHAP authentication is disabled for all calls, meaning that all attempts by the peer to force the user to authenticate using CHAP or MS-CHAP are refused.

If outbound Password Authentication Protocol (PAP) has been configured (using the ppp authentication command), PAP is suggested as the authentication method in the refusal packet.

Task ID

Task ID	Operations
ppp	read, write
aaa	read, write

Examples

The following example shows how to specify POS interface 0/3/0/1 and disable CHAP and MS-CHAP authentication from occurring if a peer calls in requesting CHAP or MS-CHAP authentication. The method of encapsulation on the interface is PPP.

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp chap refuse

Related Commands

Command	Description
aaa authentication ppp	Specifies one or more authentication, authorization, and accounting (AAA) methods for use on serial interfaces running PPP.
ppp authentication	Enables CHAP, MS-CHAP, or PAP, and specifies the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface.
ppp max-bad-auth	Configures a PPP interface not to reset itself immediately after an authentication failure but instead to allow a specified number of authentication retries.
ppp pap sent-username password	Enables remote PAP support for an interface, and includes the sent-username and password commands in the PAP authentication request packet to the peer.

ppp max-bad-auth

To configure a PPP interface not to reset itself immediately after an authentication failure but instead to allow a specified number of authentication retries, use the ppp max-bad-auth command in interface configuration mode. To reset to the default of immediate reset, use the no form of this command.

ppp max-bad-auth retries

no ppp max-bad-auth retries

Syntax Description

retries

Number of retries after which the interface is to reset itself. Range is from 0 to 10. Default is 0 retries.

Defaults

retries = 0

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp max-bad-auth command applies to any Packet-over-SONET/SDH (POS) interface on which PPP encapsulation is enabled.

Task ID

Task ID	Operations
ppp	read, write
aaa	read, write

Examples

In the following example, POS interface 0/3/0/1 is set to allow two additional retries after an initial authentication failure (for a total of three failed authentication attempts):

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp authentication chap

RP/0/RP0/CPU0:router(config-if)# ppp max-bad-auth 3

Related Commands

Command	Description
ppp authentication	Enables CHAP, MS-CHAP, or PAP, and specifies the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface.
ppp chap password	Enables a router calling a collection of routers that do not support this command (such as routers running older Cisco IOS XR software images) to configure a common CHAP secret password to use in response to challenges from an unknown peer.
ppp chap refuse	Refuses CHAP authentication from peers requesting it.
ppp pap refuse	Refuses PAP authentication from peers requesting it.
ppp pap sent-username password	Enables remote PAP support for an interface and includes the sent-username and password commands in the PAP authentication request packet to the peer.

ppp max-configure

To specify the maximum number of configure requests to attempt (without response) before stopping the requests, use the ppp max-configure command in interface configuration mode. To disable the maximum number of configure requests and return to the default, use the no form of this command.

ppp max-configure retries

no ppp max-configure retries

Syntax Description

retries

Maximum number of retries. Range is 4 through 20. Default is 10.

Defaults

retries = 10

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Use the ppp max-configure command to specify how many times an attempt is made to establish a Link Control Protocol (LCP) session between two peers for a particular interface. If a configure request message receives a reply before the maximum number of configure requests are sent, further configure requests are abandoned.

Task ID

Task ID	Operations
ppp	read, write

Examples

In the following example, a limit of four configure requests is specified:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp max-configure 4

Related Commands

Command	Description
encapsulation ppp	Enables encapsulation for communication with routers or bridges using PPP.
ppp max-failure	Configures the maximum number of CONFNAKs to permit before terminating a negotiation.
ppp max-terminate	Configures the maximum number of terminate requests to send without reply before closing down the LCP or NCP.

ppp max-failure

To configure the maximum number of consecutive Configure Negative Acknowledgments (CONFNAKs) to permit before terminating a negotiation, use the ppp max-failure command in interface configuration mode. To disable the maximum number of CONFNAKs and return to the default, use the no form of this command.

ppp max-failure retries

no ppp max-failure retries

Syntax Description

retries

Maximum number of CONFNAKs to permit before terminating a negotiation. Range is from 2 to 10. Default is 5.

Defaults

retries = 5

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
ppp	read, write

Examples

The following ppp max-failure command specifies that no more than three CONFNAKs are permitted before terminating the negotiation:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp max-failure 3

Related Commands

Command	Description
encapsulation ppp	Enables encapsulation for communication with routers or bridges using PPP.
ppp max-configure	Specifies the maximum number of configure requests to attempt (without response) before stopping the requests.
ppp max-terminate	Configures the maximum number of terminate requests to send without reply before closing down the LCP or NCP.

ppp max-terminate

To configure the maximum number of terminate requests (TermReqs) to send without reply before closing down the Link Control Protocol (LCP) or Network Control Protocol (NCP), use the ppp max-terminate command in interface configuration mode. To disable the maximum number of TermReqs and return to the default, use the no form of this command.

ppp max-terminate number

no ppp max-terminate number

Syntax Description

number

Maximum number of TermReqs to send without reply before closing down the LCP or NCP. Range is from 2 to 10. Default is 2.

Defaults

number = 2 retries

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
ppp	read, write

Examples

In the following example, a maximum of five TermReqs are specified to be sent before terminating and closing LCP or NCP:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp max-terminate 5

Related Commands

Command	Description
ppp max-configure	Specifies the maximum number of configure requests to attempt (without response) before stopping the requests.
ppp max-failure	Configures the maximum number of CONFNAKs to permit before terminating a negotiation.

ppp ms-chap password

To enable a router calling a collection of routers to configure a common Microsoft Challenge Handshake Authentication (MS-CHAP) secret password, use the ppp ms-chap password command in interface configuration mode. To disable the password, use the no form of this command.

ppp ms-chap password [clear | encrypted] line password

no ppp ms-chap password [clear | encrypted] line password

Syntax Description

clear	(Optional) Specifies the cleartext encryption parameter for the password.
encrypted	(Optional) Indicates that the password is already encrypted.
line	The UNENCRYPTED (cleartext) default password
password	Cleartext or already-encrypted password.

Defaults

The password is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.3.0	This command was introduced on the Cisco CRS-1 and the Cisco XR 12000 Series Router.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp ms-chap password command is used for remote MS-CHAP authentication only (when routers authenticate to the peer) and does not affect local MS-CHAP authentication. This command is useful for routers that do not support this command (such as routers running older Cisco IOS XR software images).

The MS-CHAP secret password is used by the routers in response to challenges from an unknown peer.

Task ID

Task ID	Operations
ppp	read, write

Examples

The following example shows how to enter a password (xxxx) as a cleartext password:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp ms-chap password clear line xxxx

ppp ms-chap refuse

To refuse Microsoft Challenge Handshake Authentication Protocol (MS-CHAP) authentication from peers requesting it, use the ppp ms-chap refuse command in interface configuration mode. To allow MS-CHAP authentication, use the no form of this command.

ppp ms-chap refuse

no ppp ms-chap refuse

Syntax Description

This command has no arguments or keywords.

Defaults

MS-CHAP authentication is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.3.0	This command was introduced on the Cisco CRS-1 and the Cisco XR 12000 Series Router.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp ms-chap refuse command specifies that MS-CHAP authentication is disabled for all calls, meaning that all attempts by the peer to force the user to authenticate using MS-CHAP are refused.

If outbound Password Authentication Protocol (PAP) has been configured (using the ppp authentication command), PAP is suggested as the authentication method in the refusal packet.

Task ID

Task ID	Operations
ppp	read, write

Examples

The following example shows how to specify POS interface 0/3/0/1 and disable MS-CHAP authentication from occurring if a peer calls in requesting MS-CHAP authentication. The method of encapsulation on the interface is PPP.

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp ms-chap refuse

ppp pap refuse

To refuse Password Authentication Protocol (PAP) authentication from peers requesting it, use the ppp pap refuse command in interface configuration mode. To allow PAP authentication, use the no form of this command.

ppp pap refuse

no ppp pap refuse

Syntax Description

This command has no arguments or keywords.

Defaults

PAP authentication is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp pap refuse command specifies that PAP authentication is disabled for all calls, meaning that all attempts by the peer to force the user to authenticate using PAP are refused.

If outbound Challenge Handshake Authentication Protocol (CHAP) has been configured (using the ppp authentication command), CHAP is suggested as the authentication method in the refusal packet.

Task ID

Task ID	Operations
ppp	read, write
aaa	read, write

Examples

The following example shows how to specify POS 0/3/0/1 using PPP encapsulation on the interface. This example shows PAP authentication being specified as disabled if a peer calls in requesting PAP authentication.

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp pap refuse

Related Commands

Command	Description
aaa authentication ppp	Specifies one or more authentication, authorization, and accounting (AAA) methods for use on serial interfaces running PPP.
ppp authentication	Enables CHAP, MS-CHAP, or PAP, and specifies the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface.
ppp max-bad-auth	Configures a PPP interface not to reset itself immediately after an authentication failure but instead to allow a specified number of authentication retries.
ppp pap sent-username password	Enables remote PAP support for an interface, and includes the sent-username and password commands in the PAP authentication request packet to the peer.

ppp pap sent-username password

To enable remote Password Authentication Protocol (PAP) support for an interface, and to use the values specified for username and password in the PAP authentication request, use the ppp pap sent-username password command in interface configuration mode. To disable remote PAP support, use the no form of this command.

ppp pap sent-username username password [clear | encrypted] password

no ppp pap sent-username username password [clear | encrypted] password

Syntax Description

username	Username sent in the PAP authentication request.
clear	(Optional) Specifies the cleartext encryption parameter for the password.
encrypted	(Optional) Indicates that the password is already encrypted.
password	Cleartext or already-encrypted password.

Defaults

Remote PAP support is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Use the ppp pap sent-username password command to enable remote PAP support (for example, to respond to the peer's request to authenticate with PAP) and to specify the parameters to be used when sending the PAP authentication request.

The ppp pap sent-username password command allows you to replace several username and password configuration commands with a single copy of this command on Packet-over-SONET/SDH (POS) interfaces.

You must configure this command for each interface.

Task ID

Task ID	Operations
ppp	read, write
aaa	read, write

Examples

In the following example, a password is entered as a cleartext password, xxxx:

RP/0/RP0/CPU0:router(config-if)# ppp pap sent-username xxxx password notified

When the password is displayed (as shown in the following example, using the show running-config command), the password notified appears as 7 1514190900:

RP/0/RP0/CPU0:router(config-if)# show running-config

interface POS0/1/0/0

 ipv4 address 10.0.0.2 255.255.255.0

 encapsulation ppp

 ppp pap password 7 1514190900

shutdown

On subsequent logins, entering any of the three following commands would have the same effect of making xxxx the password for remote PAP authentication:

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/0

RP/0/RP0/CPU0:router(config-if)# ppp pap sent-username xxxx password notified

RP/0/RP0/CPU0:router(config-if)# ppp pap sent-username xxxx password 0 notified

RP/0/RP0/CPU0:router(config-if)# ppp pap sent-username xxxx 7 1514190900

Related Commands

Command	Description
aaa authentication ppp	Specifies one or more authentication, authorization, and accounting (AAA) methods for use on serial interfaces running PPP.
ppp authentication	Enables CHAP, MS-CHAP, or PAP, and specifies the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface.
ppp pap refuse	Refuses PAP authentication from peers requesting it
ppp timeout authentication	Sets PPP authentication timeout parameters.
show running-config	Displays the contents of the currently running configuration file or the configuration for a specific interface, or map class information.

ppp timeout authentication

To set PPP authentication timeout parameters, use the ppp timeout authentication command in interface configuration mode. To reset the default value, use the no form of this command.

ppp timeout authentication seconds

no ppp timeout authentication seconds

Syntax Description

seconds

Maximum time, in seconds, to wait for a response to an authentication packet. Range is from 3 to 30 seconds. Default is 10 seconds.

Defaults

seconds = 10

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The default authentication time is 10 seconds, which should allow time for a remote router to authenticate and authorize the connection and provide a response. However, it is also possible that it will take much less time than 10 seconds. In such cases, use the ppp timeout authentication command to lower the timeout period to improve connection times in the event that an authentication response is lost.

---

Note The timeout affects connection times only if packets are lost and time out.

---

Task ID

Task ID	Operations
ppp	read, write

Examples

In the following example, PPP timeout authentication is set to 20 seconds:

RP/0/RP0/CPU0:router# configuration

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp timeout authentication 20

Related Commands

Command	Description
aaa authentication ppp	Specifies one or more authentication, authorization, and accounting (AAA) methods for use on serial interfaces running PPP.
ppp authentication	Enables CHAP, MS-CHAP, or PAP, and specifies the order in which CHAP, MS-CHAP, and PAP authentication is selected on the interface.

ppp timeout retry

To set PPP timeout retry parameters, use the ppp timeout retry command in interface configuration mode. To reset the time value, use the no form of this command.

ppp timeout retry seconds

no ppp timeout retry

Syntax Description

seconds

Maximum time, in seconds, to wait for a response during PPP negotiation. Range is from 1 to 10 seconds. Default is 3 seconds.

Defaults

seconds = 3

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The ppp timeout retry command is useful for setting a maximum amount of time PPP should wait for a response to any control packet it sends.

Task ID

Task ID	Operations
ppp	read, write

Examples

The following example shows the retry timer being set to 8 seconds:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1

RP/0/RP0/CPU0:router(config-if)# encapsulation ppp

RP/0/RP0/CPU0:router(config-if)# ppp timeout retry 8

Related Commands

Command	Description
keepalive	Controls how often LCP EchoRequest packets are sent after LCP has been negotiated.
ppp timeout authentication	Sets PPP authentication timeout parameters.

show interfaces pos

To display information about a POS interface, use the show interfaces pos command in EXEC mode.

show interfaces pos [instance] [accounting [rates] | brief | description | detail | summary] [location node-id]

instance	(Optional) POS interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation. –rack—Chassis number of the rack. –slot—Physical slot number of the modular services card or line card. –module—Module number. A physical layer interface module (PLIM) is always 0. –port—Physical port number of the interface. For more information about the syntax for the router, use the question mark (?) online help function.
accounting	(Optional) Displays accounting information for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
rates	(Optional) Displays interface accounting rates for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
brief	(Optional) Displays brief output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
description	Displays descriptive output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
detail	(Optional) Displays detailed output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
location node-id	(Optional) Displays detailed POS information for the designated node. The node-id argument is entered in the rack/slot/module notation.
summary	(Optional) Displays summarized POS interface information.

Defaults

Enter the show interfaces pos command without including any of the optional keywords or arguments to display detailed information about all POS interfaces configured on the router.

Command Modes

EXEC

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs.

Task ID

Task ID	Operations
interface	read

Examples

The following example shows how to display summarized information for a POS interface on a specific node:

RP/0/RP0/CPU0:router# show interfaces pos summary location 0/1/CPU0

Interface Type          Total    UP       Down     Admin Down

--------------          -----    --       ----     ----------

ALL TYPES               4        1        1        2

--------------

IFT_POS                 4        1        1        2

Table 74 describes the significant fields shown in the display.

Table 74 show interfaces pos summary Field Descriptions 

Field	Description
Intf Type	Type of interface described in the display.
Total	Total number of configured interfaces of the specified type.
Up	Number of interfaces of the specified type that are in the "Up" state.
Down	Number of interfaces of the specified type that are in the "Down" state.
Admin Down	Number of interfaces of the specified type that are in the "Admin Down" state.

The following example shows how to display brief information for a specific POS interface:

RP/0/RP0/CPU0:router# show interfaces pos 0/2/0/0 brief

              Intf        Intf         LineP              Encap  MTU       BW

              Name        State        State               Type (byte)   (Kbps)

-------------------------------------------------------------------------------

         PO0/2/0/0   admin-down   admin-down               HDLC  4474   2488320

P/0/RP1/CPU0:MiniQ#

Table 75 describes the significant fields shown in the display.

Table 75 show interfaces pos Field Descriptions 

Field	Description
Intf Name	Interface identifier, in the type*rack/slot/module/port notation.
Intf State	Indicates whether the interface is in the admin-up or admin down state.
LineP State	Current state of the protection line.
Encap Type	Encapsulation type for the specified interface. Can be HDLC or PPP.
MTU (byte)	Maximum transmission unit (MTU) value configured for the specified interface, in bytes.
BW (Kbps)	Bandwidth of the interface, in kbps.

Related Commands

Command	Description
show controllers pos	Displays information on the SONET controllers that are associated with Packet-over-SONET/SDH (POS) interfaces.
show controllers sonet	Displays information about the operational status of SONET layers.

show ppp interfaces

To display PPP state information for an interface, use the show ppp interfaces command in EXEC mode.

show ppp interfaces {POS instance | all | brief {POS interface_instance | all | location node-id} | detail {POS interface_instance | all | location node-id} | location node-id}

Syntax Description

POS	Specifies the interface type as Packet-over-SONET/SDH (POS).
instance	Either a physical interface instance or a virtual interface instance as follows: •Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation. –rack: Chassis number of the rack. –slot: Physical slot number of the modular services card or line card. –module: Module number. A physical layer interface module (PLIM) is always 0. –port: Physical port number of the interface. •Virtual interface instance. Number range varies depending on interface type. For more information about the syntax for the router, use the question mark (?) online help function.
all	(Optional) Displays detailed PPP information for all nodes.
brief	(Optional) Displays brief output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
detail	(Optional) Displays detailed output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node.
location node-id	(Optional) Displays detailed PPP information for the designated node. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

There are seven possible PPP states applicable for either the Link Control Protocol (LCP) or the Network Control Protocol (NCP).

---

Note If IPv6 is enabled on the interface, then the IPV6 link-local address appears in the second line of the show ppp interfaces command output.

---

Task ID

Task ID	Operations
ppp	read

Examples

The following example shows how to display PPP state information for POS interface 0/2/0/0:

RP/0/RP0/CPU0:router# show ppp interfaces POS 0/2/0/0

  POS0/2/0/0 is up, line protocol is up

  Internet address is 10.0.0.1/24

  MRU 4470 bytes

  Keepalive set (10 sec)

  LCP Open

  Closed: IPCP

Table 76 describes the significant fields shown in the display.

Table 76 show ppp interfaces Field Descriptions 

Field	Description
Internet address	IP address of the specified interface.
MRU	Maximum receive unit. The maximum size of the information transported, in bytes, in the PPP packet received by the local equipment.
Keepalive	Keepalive setting and interval in seconds for echo request packets.
LCP	Indicates the current state of LCP. The state of the LCP will report the following states: •Open—LCP is functioning properly. •Listen—LCP has tried to negotiate with the peer machine, but failed. •REQsent—LCP is attempting to negotiate with the peer machine; it has sent LCP packets, but not yet received a response. •ACKsent—LCP has received a request and has replied to it. •ACKrcvd—LCP has received a reply to a request it sent. •TERMsent—LCP has sent a TERMreq message to the peer machine. Closed— LCP is not currently trying to negotiate.
Closed	IPCP NCP is in the "closed" state. The last line(s) of the display show each of the seven states that are occupied by any of the NCPs, followed by a list of the NCPs in that state. If no NCPS occupy any of the seven states, this information will not be displayed. The seven possible states that may be displayed in these last lines are as follows: •Open—The indicated NCP is functioning properly. •Listen—The indicated NCP has tried to negotiate with the peer machine, but failed. •REQsent—The indicated NCP is attempting to negotiate with the peer machine; it has sent packets, but not yet received a response. •ACKsent—The indicated NCP has received a request and has replied to it. •ACKrcvd—The indicated NCP has received a reply to a request it sent. •TERMsent—The indicated NCP has sent a TERMreq message to the peer machine. •Closed—The indicated NCP is not currently trying to negotiate.

Related Commands

Command	Description
encapsulation ppp	Enables encapsulation for communication with routers or bridges using PPP.
ipv4 address	Specifies an IPv4 family address.
ipv6 address	Specifies an IPv6 family address.
keepalive	Controls how often LCP EchoRequest packets are sent after LCP has been negotiated.
mtu	Specifies the MTU to be used.

transmit-delay

To specify a number of flag sequences to be inserted between the packets, use the transmit-delay command in POS configuration mode. To restore the default, use the no form of this command.

transmit-delay microseconds

no transmit-delay microseconds

Syntax Description

microseconds

Number of microseconds of minimum delay after sending a packet. Range is from 0 to 1023. Default is 0 (disabled).

Defaults

microseconds = 0 (disabled)

Command Modes

POS configuration

Command History

Releases	Modifications
Release 3.2	This command was introduced on the Cisco CRS-1 and the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
pos-dpt	read, write

Examples

In the following example, a delay of 2 microseconds is specified on POS interface 0/1/0/2:

RP/0/0/CPU0:router# configure

RP/0/0/CPU0:router(config)# interface POS 0/1/0/2

RP/0/0/CPU0:router(config-if)# pos

RP/0/0/CPU0:router(config-if-pos)# transmit-delay 2

In the following example, the transmit delay on POS interface 0/1/0/2 is disabled:

RP/0/0/CPU0:router# configure

RP/0/0/CPU0:router(config)# interface POS 0/1/0/2

RP/0/0/CPU0:router(config-if)# pos

RP/0/0/CPU0:router(config-if-pos)# no transmit-delay

Related Commands

Command	Description
show interfaces	Displays statistics for all interfaces configured on the router or on a specific node or on a specific node.