Cisco ASR 900 Series User manual

Time Division Multiplexing Configuration Guide, Cisco IOS XE Fuji
16.7.x (Cisco ASR 900 Series)
First Published: 2017-11-17
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CONTENTS
CHAPTER 1 Configuring Pseudowire 1
Pseudowire Overview 1
Limitations 2
Circuit Emulation Overview 3
Structure-Agnostic TDM over Packet 3
Circuit Emulation Service over Packet-Switched Network 4
Asynchronous Transfer Mode over MPLS 6
Transportation of Service Using Ethernet over MPLS 7
Limitations 7
Configuring CEM 8
Configuration Guidelines and Restrictions 8
Configuring a CEM Group 8
Using CEM Classes 10
Configuring a Clear-Channel ATM Interface 12
Configuring CEM Parameters 12
Configuring Payload Size (Optional) 12
Setting the Dejitter Buffer Size 13
Setting an Idle Pattern (Optional) 13
Enabling Dummy Mode 13
Setting a Dummy Pattern 13
Shutting Down a CEM Channel 13
Configuring CAS 14
Information About CAS 14
Configuring CAS 14
Verifying CAS Configuration 16
Configuration Examples for CAS 16
Configuring ATM 17
Configuring a Clear-Channel ATM Interface 17
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Configuring ATM IMA 18
BGP PIC with TDM Configuration 21
Configuring Structure-Agnostic TDM over Packet (SAToP) 21
Configuring Circuit Emulation Service over Packet-Switched Network (CESoPSN) 23
Configuring a Clear-Channel ATM Pseudowire 24
Configuring an ATM over MPLS Pseudowire 26
Configuring the Controller 26
Configuring an IMA Interface 27
Configuring the ATM over MPLS Pseudowire Interface 29
Configuring 1-to-1 VCC Cell Transport Pseudowire 30
Mapping a Single PVC to a Pseudowire 30
Configuring N-to-1 VCC Cell Transport Pseudowire 31
Configuring 1-to-1 VPC Cell Transport 31
Configuring ATM AAL5 SDU VCC Transport 33
Configuring a Port Mode Pseudowire 35
Optional Configurations 36
Configuring an Ethernet over MPLS Pseudowire 37
Configuring Pseudowire Redundancy 39
Pseudowire Redundancy with Uni-directional Active-Active 41
Restrictions 42
Configuring Pseudowire Redundancy Active-Active—Protocol Based 43
Configuring the Working Controller for MR-APS with Pseudowire Redundancy
Active-Active 43
Configuring the Protect Controller for MR-APS with Pseudowire Redundancy
Active-Active 44
Verifying the Interface Configuration 44
Configuration Examples 45
Example: CEM Configuration 45
Example: BGP PIC with TDM Configuration 45
Example: BGP PIC with TDM-PW Configuration 46
Example: ATM IMA Configuration 47
Example: ATM over MPLS 47
Cell Packing Configuration Examples 48
VC Mode 48
VP Mode 49
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Contents

Cell Relay Configuration Examples 51
VC Mode 51
VP Mode 52
Example: Ethernet over MPLS 53
CHAPTER 2 Automatic Protection Switching Configuration 57
Automatic Protection Switching 57
Inter Chassis Redundancy Manager 58
Limitations 58
Automatic Protection Switching Interfaces Configuration 59
Configuring a Working Interface 59
Configuring a Protect Interface 60
Configuring Other APS Options 61
Stateful MLPPP Configuration with MR-APS Inter-Chassis Redundancy 63
Monitoring and Maintaining APS 63
CHAPTER 3 Configuring Multi Router Automatic Protection Switching 65
Finding Feature Information 66
Restrictions for MR-APS 66
Information About MR-APS 66
Configuring MR-APS with HSPW-ICRM on a CEM interface 69
Verifying MR-APS 74
Configuration Examples for MR-APS 82
Configuring MR-APS on a POS interface 84
Configuring working node for POS MR-APS 84
Configuring protect node for POS MR-APS 87
Verifying MR-APS on POS interface 91
Configuration Examples for MR-APS on POS interface 93
CHAPTER 4 Hot Standby Pseudowire Support for ATM and TDM Access Circuits 95
Finding Feature Information 95
Prerequisites for Hot Standby Pseudowire Support for ATM and TDM Access Circuits 96
Restrictions for Hot Standby Pseudowire Support for ATM and TDM Access Circuits 96
Information About Hot Standby Pseudowire Support for ATM and TDM Access Circuits 97
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How the Hot Standby Pseudowire Support for ATM and TDM Access Circuits Feature
Works 97
Supported Transport Types 97
How to Configure Hot Standby Pseudowire Support for ATM and TDM Access Circuits 98
Configuring a Pseudowire for Static VPLS 98
Configuring Hot Standby Pseudowire Support for ATM and TDM Access Circuits 100
Verifying the Hot Standby Pseudowire Support for ATM and TDM Access Circuits
Configuration 102
Configuration Examples for Hot Standby Pseudowire Support for ATM and TDM Access
Circuits 104
Configuring Hot Standby Pseudowire Support for ATM and TDM Access Circuits on CEM
Circuits Example 104
Additional References 105
CHAPTER 5 PPP and Multilink PPP Configuration 107
Limitations 107
PPP and Multilink PPP 108
Point-to-Point Protocol 108
CHAP or PPP Authentication 108
IP Address Pooling 109
Peer Address Allocation 109
Precedence Rules 110
MLP on Synchronous Serial Interfaces 111
How to Configure PPP 111
Enabling PPP Encapsulation 111
Enabling CHAP or PAP Authentication 112
Configuring IP Address Pooling 114
Global Default Address Pooling Mechanism 114
Defining DHCP as the Global Default Mechanism 114
Defining Local Address Pooling as the Global Default Mechanism 116
Controlling DHCP Network Discovery 117
Configuring IP Address Assignment 118
Disabling or Reenabling Peer Neighbor Routes 119
Configuring Multilink PPP 120
Configuring MLP on Synchronous Interfaces 121
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Contents

Configuring a Multilink Group 122
Configuring PFC and ACFC 124
Configuring ACFC 124
Configuring PFC 125
Changing the Default Endpoint Discriminator 126
Creating a Multilink Bundle 128
Assigning an Interface to a Multilink Bundle 129
Configuring PPP/MLP MRRU Negotiation Configuration on Multilink Groups 130
Disabling PPP Multilink Fragmentation 133
Troubleshooting Tips 134
Troubleshooting PPP 134
Monitoring and Maintaining PPP and MLP Interfaces 134
CHAPTER 6 Transparent SONET or SDH over Packet (TSoP) Protocol 135
Prerequisites for TSoP 135
Restrictions for TSoP 135
Information About TSoP Smart SFP 136
Guidelines for TSoP Smart SFP 136
Configuring the Reference Clock 137
Configuration Examples for TSoP 139
Verification Examples 140
Verifying TSoP Smart SFP 140
Verifying Clock Source 141
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Contents

CHAPTER 1
Configuring Pseudowire
This chapter provides information about configuring pseudowire (PW) features on the router.
•Pseudowire Overview, page 1
•Limitations, page 7
•Configuring CEM, page 8
•Configuring CAS, page 14
•Configuring ATM, page 17
•Configuring Structure-Agnostic TDM over Packet (SAToP), page 21
•Configuring Circuit Emulation Service over Packet-Switched Network (CESoPSN), page 23
•Configuring a Clear-Channel ATM Pseudowire, page 24
•Configuring an ATM over MPLS Pseudowire, page 26
•Configuring an Ethernet over MPLS Pseudowire, page 37
•Configuring Pseudowire Redundancy, page 39
•Pseudowire Redundancy with Uni-directional Active-Active , page 41
•Restrictions , page 42
•Configuring Pseudowire Redundancy Active-Active—Protocol Based, page 43
•Configuring the Working Controller for MR-APS with Pseudowire Redundancy Active-Active, page
43
•Configuring the Protect Controller for MR-APS with Pseudowire Redundancy Active-Active, page 44
•Verifying the Interface Configuration, page 44
•Configuration Examples, page 45
Pseudowire Overview
The following sections provide an overview of pseudowire support on the router.
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Effective Cisco IOS XE Release 3.18S:
•BGP PIC with TDM Pseudowire is supported on the ASR 900 router with RSP2 module.
•BGP PIC for Pseudowires, with MPLS Traffic Engineering is supported on the ASR 900 router with
RSP1 and RSP2 modules.
Starting Cisco IOS XE Release 3.18.1SP, Pseudowire Uni-directional Active-Active is supported on the RSP1
and RSP3 modules.
Limitations
If you are running Cisco IOS XE Release 3.17S, the following limitation applies:
•BGP PIC with TDM Pseudowire is supported only on the ASR 900 router with RSP1 module.
If you are running Cisco IOS XE Release 3.17S and later releases, the following limitations apply:
•Channel associated signaling (CAS) is not supported on the T1/E1 and OC-3 interface modules on the
router.
•BGP PIC is not supported for MPLS/LDP over MLPPP and POS in the core.
•BGP PIC is not supported for Multi-segment Pseudowire or Pseudowire switching.
•BGP PIC is not supported for VPLS and H-VPLS
.
•BGP PIC is not supported for IPv6.
•If BGP PIC is enabled, Multi-hop BFD should not be configured using the bfd neighbor fall-overrbfd
command.
•If BGP PIC is enabled, neighbor ip-address weight weight command should not be configured.
•If BGP PIC is enabled, bgp nexthop trigger delay 6 under the address-family ipv4 command and bgp
nexthop trigger delay 7 under the address-family vpnv4 command should be configured. For
information on the configuration examples for BGP PIC–TDM, see Example: BGP PIC with TDM-PW
Configuration, on page 46.
•If BGP PIC is enabled and the targeted LDP for VPWS cross-connect services are established over BGP,
perform the following tasks:
◦configure Pseudowire-class (pw-class) with encapsulation "mpls"
◦configure no status control-plane route-watch under the pw-class
◦associate the pw-class with the VPWS cross-connect configurations
If you are running Cisco IOS-XE 3.18S, the following restrictions apply for BGP PIC with MPLS TE for
TDM Pseudowire:
•MPLS TE over MLPPP and POS in the core is not supported.
•Co-existence of BGP PIC with MPLS Traffic Engineering Fast Reroute (MPLS TE FRR) is not supported.
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Configuring Pseudowire
Limitations

Circuit Emulation Overview
Circuit Emulation (CEM) is a technology that provides a protocol-independent transport over IP networks. It
enables proprietary or legacy applications to be carried transparently to the destination, similar to a leased
line.
The Cisco ASR 903 Series Router supports two pseudowire types that utilize CEM transport: Structure-Agnostic
TDM over Packet (SAToP) and Circuit Emulation Service over Packet-Switched Network (CESoPSN). The
following sections provide an overview of these pseudowire types.
Starting with Cisco IOS XE Release 3.15, the 32xT1E1 and 8x T1/E1 interface modules support CEM CESoP
and SATOP configurations with fractional timeslots.
With the 32xT1/E1 and 8xT1/E1 interface modules, the channelized CEM circuits configured under a single
port (fractional timeslot) cannot be deleted or modified, unless the circuits created after the first CEM circuits
are deleted or modified.
The following CEM circuits are supported on the 32xT1/E1 interface module:
T1 mode
•192 CESOP circuits with fractional timeslot ◦
◦32 CESOP circuit full timeslot
◦32 SATOP circuits.
E1 mode
•256 CESOP circuit with fractional timeslot. ◦
◦32 CESOP circuit full timeslot
◦32 SATOP circuit
Structure-Agnostic TDM over Packet
SAToP encapsulates time division multiplexing (TDM) bit-streams (T1, E1, T3, E3) as PWs over public
switched networks. It disregards any structure that may be imposed on streams, in particular the structure
imposed by the standard TDM framing.
The protocol used for emulation of these services does not depend on the method in which attachment circuits
are delivered to the provider edge (PE) devices. For example, a T1 attachment circuit is treated the same way
for all delivery methods, including copper, multiplex in a T3 circuit, a virtual tributary of a SONET/SDH
circuit, or unstructured Circuit Emulation Service (CES).
In SAToP mode the interface is considered as a continuous framed bit stream. The packetization of the stream
is done according to IETF RFC 4553. All signaling is carried out transparently as a part of a bit stream. Figure
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Configuring Pseudowire
Circuit Emulation Overview

1: Unstructured SAToP Mode Frame Format, on page 4 shows the frame format in Unstructured SAToP
mode.
Figure 1: Unstructured SAToP Mode Frame Format
Table 1: SAToP T1 Frame: Payload and Jitter Limits, on page 4 shows the payload and jitter limits for the
T1 lines in the SAToP frame format.
Table 1: SAToP T1 Frame: Payload and Jitter Limits
Minimum JitterMaximum JitterMinimum
Payload
Minimum JitterMaximum JitterMaximum
Payload
26419210320960
Table 2: SAToP E1 Frame: Payload and Jitter Limits, on page 4 shows the payload and jitter limits for the
E1 lines in the SAToP frame format.
Table 2: SAToP E1 Frame: Payload and Jitter Limits
Minimum JitterMaximum JitterMinimum
Payload
Minimum JitterMaximum JitterMaximum
Payload
264256103201280
For instructions on how to configure SAToP, see Configuring Structure-Agnostic TDM over Packet (SAToP),
on page 21.
Circuit Emulation Service over Packet-Switched Network
CESoPSN encapsulates structured TDM signals as PWs over public switched networks (PSNs). It complements
similar work for structure-agnostic emulation of TDM bit streams, such as SAToP. Emulation of circuits saves
PSN bandwidth and supports DS0-level grooming and distributed cross-connect applications. It also enhances
resilience of CE devices due to the effects of loss of packets in the PSN.
CESoPSN identifies framing and sends only the payload, which can either be channelized T1s within DS3 or
DS0s within T1. DS0s can be bundled to the same packet. The CESoPSN mode is based on IETF RFC 5086.
Each supported interface can be configured individually to any supported mode. The supported services
comply with IETF and ITU drafts and standards.
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Configuring Pseudowire
Circuit Emulation Service over Packet-Switched Network

Figure 2: Structured CESoPSN Mode Frame Format, on page 5 shows the frame format in CESoPSN mode.
Figure 2: Structured CESoPSN Mode Frame Format
Table 3: CESoPSN DS0 Lines: Payload and Jitter Limits, on page 5 shows the payload and jitter for the
DS0 lines in the CESoPSN mode.
Table 3: CESoPSN DS0 Lines: Payload and Jitter Limits
Minimum
Jitter
Maximum
Jitter
Minimum
Payload
Minimum
Jitter
Maximum
Jitter
Maximum
Payload
DS0
82563210320401
41283210320802
412833103201203
26432103201604
26440103202005
26448103202406
26456103202807
26464103203208
26472103203609
264801032040010
264881032044011
264961032048012
2641041032052013
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Configuring Pseudowire
Circuit Emulation Service over Packet-Switched Network

Minimum
Jitter
Maximum
Jitter
Minimum
Payload
Minimum
Jitter
Maximum
Jitter
Maximum
Payload
DS0
2641121032056014
2641201032060015
2641281032064016
2641361032068017
2641441032072018
2641521032076019
2641601032080020
2641681032084021
2641761032088022
2641841032092023
2641921032096024
26420010320100025
26420810320104026
26421610320108027
26422410320112028
26423210320116029
26424010320120030
26424810320124031
26425610320128032
For instructions on how to configure SAToP, see Configuring Structure-Agnostic TDM over Packet (SAToP),
on page 21.
Asynchronous Transfer Mode over MPLS
An ATM over MPLS (AToM) PW is used to carry Asynchronous Transfer Mode (ATM) cells over an MPLS
network. It is an evolutionary technology that allows you to migrate packet networks from legacy networks,
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Configuring Pseudowire
Asynchronous Transfer Mode over MPLS

while providing transport for legacy applications. AToM is particularly useful for transporting 3G voice traffic
over MPLS networks.
You can configure AToM in the following modes:
•N-to-1 Cell—Maps one or more ATM virtual channel connections (VCCs) or virtual permanent connection
(VPCs) to a single pseudowire.
•1-to-1 Cell—Maps a single ATM VCC or VPC to a single pseudowire.
•Port—Maps a single physical port to a single pseudowire connection.
The Cisco ASR 903 Series Router also supports cell packing and PVC mapping for AToM pseudowires.
This release does not support AToM N-to-1 Cell Mode or 1-to-1 Cell Mode.Note
For more information about how to configure AToM, see Configuring an ATM over MPLS Pseudowire, on
page 26.
Transportation of Service Using Ethernet over MPLS
Ethernet over MPLS (EoMPLS) PWs provide a tunneling mechanism for Ethernet traffic through an
MPLS-enabled Layer 3 core network. EoMPLS PWs encapsulate Ethernet protocol data units (PDUs) inside
MPLS packets and use label switching to forward them across an MPLS network. EoMPLS PWs are an
evolutionary technology that allows you to migrate packet networks from legacy networks while providing
transport for legacy applications. EoMPLS PWs also simplify provisioning, since the provider edge equipment
only requires Layer 2 connectivity to the connected customer edge (CE) equipment. The Cisco ASR 903
Series Router implementation of EoMPLS PWs is compliant with the RFC 4447 and 4448 standards.
The Cisco ASR 903 Series Router supports VLAN rewriting on EoMPLS PWs. If the two networks use
different VLAN IDs, the router rewrites PW packets using the appropriate VLAN number for the local network.
For instructions on how to create an EoMPLS PW, see Configuring an Ethernet over MPLS Pseudowire, on
page 37.
Limitations
If you are running Cisco IOS XE Release 3.17S, the following limitation applies:
•BGP PIC with TDM Pseudowire is supported only on the ASR 900 router with RSP1 module.
If you are running Cisco IOS XE Release 3.17S and later releases, the following limitations apply:
•Channel associated signaling (CAS) is not supported on the T1/E1 and OC-3 interface modules on the
router.
•BGP PIC is not supported for MPLS/LDP over MLPPP and POS in the core.
•BGP PIC is not supported for Multi-segment Pseudowire or Pseudowire switching.
•BGP PIC is not supported for VPLS and H-VPLS
.
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Configuring Pseudowire
Transportation of Service Using Ethernet over MPLS

•BGP PIC is not supported for IPv6.
•If BGP PIC is enabled, Multi-hop BFD should not be configured using the bfd neighbor fall-overrbfd
command.
•If BGP PIC is enabled, neighbor ip-address weight weight command should not be configured.
•If BGP PIC is enabled, bgp nexthop trigger delay 6 under the address-family ipv4 command and bgp
nexthop trigger delay 7 under the address-family vpnv4 command should be configured. For
information on the configuration examples for BGP PIC–TDM, see Example: BGP PIC with TDM-PW
Configuration, on page 46.
•If BGP PIC is enabled and the targeted LDP for VPWS cross-connect services are established over BGP,
perform the following tasks:
◦configure Pseudowire-class (pw-class) with encapsulation "mpls"
◦configure no status control-plane route-watch under the pw-class
◦associate the pw-class with the VPWS cross-connect configurations
If you are running Cisco IOS-XE 3.18S, the following restrictions apply for BGP PIC with MPLS TE for
TDM Pseudowire:
•MPLS TE over MLPPP and POS in the core is not supported.
•Co-existence of BGP PIC with MPLS Traffic Engineering Fast Reroute (MPLS TE FRR) is not supported.
Configuring CEM
This section provides information about how to configure CEM. CEM provides a bridge between a time-division
multiplexing (TDM) network and a packet network, such as Multiprotocol Label Switching (MPLS). The
router encapsulates the TDM data in the MPLS packets and sends the data over a CEM pseudowire to the
remote provider edge (PE) router. Thus, function as a physical communication link across the packet network.
The following sections describe how to configure CEM:
Steps for configuring CEM features are also included in the Configuring Structure-Agnostic TDM over
Packet (SAToP), on page 21 and Configuring Circuit Emulation Service over Packet-Switched Network
(CESoPSN), on page 23 sections.
Note
Configuration Guidelines and Restrictions
Not all combinations of payload size and dejitter buffer size are supported. If you apply an incompatible
payload size or dejitter buffer size configuration, the router rejects it and reverts to the previous configuration.
Configuring a CEM Group
The following section describes how to configure a CEM group on the Cisco ASR 903 Series Router.
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Configuring Pseudowire
Configuring CEM

SUMMARY STEPS
1. enable
2. configure terminal
3. controller {t1 | e1} slot/subslot/port
4. cem-group group-number {unframed |timeslots timeslot}
5. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enable
Step 1
Example:
Router> enable
•Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:
Router# configure terminal
Step 2
Enters controller configuration mode.
controller {t1 | e1} slot/subslot/port
Step 3
Example:
Router(config)# controller t1 1/0
•Use the slot and port arguments to specify the slot number and port
number to be configured.
The slot number is always
0.
Note
Creates a circuit emulation channel from one or more time slots of a T1 or
E1 line.
cem-group group-number {unframed |
timeslots timeslot}
Step 4
Example:
Router(config-controller)# cem-group
6 timeslots 1-4,9,10
•The group-number keyword identifies the channel number to be
used for this channel. For T1 ports, the range is 0 to 23. For E1 ports,
the range is 0 to 30.
•Use the unframed keyword to specify that a single CEM channel is
being created including all time slots and the framing structure of the
line.
•Use the timeslots keyword and the timeslot argument to specify the
time slots to be included in the CEM channel. The list of time slots
may include commas and hyphens with no spaces between the
numbers.
Exits controller configuration mode and returns to privileged EXEC mode.end
Example:
Router(config-controller)# end
Step 5
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Configuring Pseudowire
Configuring a CEM Group

Using CEM Classes
A CEM class allows you to create a single configuration template for multiple CEM pseudowires. Follow
these steps to configure a CEM class:
The CEM parameters at the local and remote ends of a CEM circuit must match; otherwise, the pseudowire
between the local and remote PE routers will not come up.
Note
You cannot apply a CEM class to other pseudowire types such as ATM over MPLS.Note
SUMMARY STEPS
1. enable
2. configure terminal
3. class cem cem-class
4. payload-size size | dejitter-buffer buffer-size | idle-pattern pattern
5. exit
6. interface cem slot/subslot
7. exit
8. exit
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enable
Step 1
Example:
Router> enable
•Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:
Router# configure terminal
Step 2
Creates a new CEM class
class cem cem-class
Example:
Router(config)# class cem mycemclass
Step 3
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Configuring Pseudowire
Using CEM Classes

PurposeCommand or Action
Enter the configuration commands common to the
CEM class. This example specifies a sample rate,
payload size, dejitter buffer, and idle pattern.
payload-size size | dejitter-buffer buffer-size | idle-pattern
pattern
Example:
Router(config-cem-class)# payload-size 512
Step 4
Example:
Router(config-cem-class)# dejitter-buffer 10
Example:
Router(config-cem-class)# idle-pattern 0x55
Returns to the config prompt.exit
Example:
Router(config-cem-class)# exit
Step 5
Configure the CEM interface that you want to use for
the new CEM class.
interface cem slot/subslot
Example:
Step 6
The use of the xconnect command can vary
depending on the type of pseudowire you
are configuring.
Note
Example:
Router(config)# interface cem 0/0
Example:
Router(config-if)# no ip address
Example:
Router(config-if)# cem 0
Example:
Router(config-if-cem)# cem class mycemclass
Example:
Router(config-if-cem)# xconnect 10.10.10.10 200
encapsulation mpls
Example:
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Configuring Pseudowire
Using CEM Classes

PurposeCommand or Action
Exits the CEM interface.exit
Example:
Router(config-if-cem)# exit
Step 7
Example:
Exits configuration mode.exit
Example:
Router(config-if)# exit
Step 8
Example:
Configuring a Clear-Channel ATM Interface
Configuring CEM Parameters
The following sections describe the parameters you can configure for CEM circuits.
The CEM parameters at the local and remote ends of a CEM circuit must match; otherwise, the pseudowire
between the local and remote PE routers will not come up.
Note
Configuring Payload Size (Optional)
To specify the number of bytes encapsulated into a single IP packet, use the pay-load size command. The size
argument specifies the number of bytes in the payload of each packet. The range is from 32 to 1312 bytes.
Default payload sizes for an unstructured CEM channel are as follows:
•E1 = 256 bytes
•T1 = 192 bytes
•DS0 = 32 bytes
Default payload sizes for a structured CEM channel depend on the number of time slots that constitute the
channel. Payload size (L in bytes), number of time slots (N), and packetization delay (D in milliseconds) have
the following relationship: L = 8*N*D. The default payload size is selected in such a way that the packetization
Time Division Multiplexing Configuration Guide, Cisco IOS XE Fuji 16.7.x (Cisco ASR 900 Series)
12
Configuring Pseudowire
Configuring a Clear-Channel ATM Interface