Configuring ATM-over-SHDSL Interfaces

J Series devices with G.SHDSL interfaces can use an Asynchronous Transfer Mode (ATM) interface to send network traffic through a point-to-point connection to a DSL access multiplexer (DSLAM).

Note: You can configure J Series devices with a G.SHDSL interface for connections through SHDSL only, not for direct ATM connections.

J Series devices with a 2-port G.SHDSL interface installed support the following modes. You can configure only one mode on each interface.

2-port two-wire mode (Annex A or Annex B)—Supports autodetection of the line rate or fixed line rates and provides network speeds from 192 Kbps to 2.3 Mbps in 64-Kbps increments. Two-wire mode provides two separate, slower SHDSL interfaces.
1-port four-wire mode (Annex A or Annex B)—Supports fixed line rates only and provides network speeds from 384 Kbps to 4.6 Mbps in 128-Kbps increments, doubling the bandwidth. Four-wire mode provides a single, faster SHDSL interface.

To configure Point-to-Point Protocol (PPP), see the Junos Network Interfaces Configuration Guide.

You configure the underlying G.SHDSL interface as an ATM interface, with an interface name of at-pim/0/port. Multiple encapsulation types are supported on both the physical and logical ATM-over-SHDSL interface.

This section contains the following topics:

Adding an ATM-over-SHDSL Interface with a Configuration Editor

Adding an ATM-over-SHDSL Interface with a Configuration Editor

To configure ATM-over-SHDSL network interfaces for the J Series device with a configuration editor:

Navigate to the top of the interfaces configuration hierarchy.
Perform the configuration tasks described in Table 46.
If you are finished configuring the J Series device, commit the configuration.
Go on to one of the following procedures:
- To enable authentication on the interface, see Configuring CHAP on DSL Interfaces (Optional).
- To configure PPP over Ethernet (PPPoE) encapsulation on an Ethernet interface or on an ATM-over-SHDSL interface, see Understanding Point-to-Point Protocol over Ethernet.
To check the configuration, see Verifying DSL Interface Configuration.

Table 46: Adding an ATM-over-SHDSL Network Interface

Task	CLI Configuration Editor
Navigate to the Chassis level in the configuration hierarchy.	From the [edit] hierarchy level, enter set chassis fpc 6 pic 0 shdsl pic-mode 1-port-atm
Set the ATM-over-SHDSL mode on the G.SHDSL interface, if required. By default, G.SHDSL interfaces are enabled in two-wire Annex B mode. To configure the four-wire mode on the G.SHDSL interface, follow the tasks in this table.
Navigate to the Interfaces level in the configuration hierarchy.
Create the new interface—for example, at-2/0/0.
Configuring Physical Properties
Configure ATM virtual path identifier (VPI) options for the interface—for example, at-2/0/0. ATM VPI—A number between 0 and 255—for example, 25. Operation, Maintenance, and Administration (OAM) F5 loopback cell thresholds (“liveness”) on ATM virtual circuits. The range is between 1 and 255, and the default is 5 cells. Down count—Number of consecutive OAM loopback cells an ATM virtual circuit must lose to be identified as unavailable—for example, 200. Up count—Number of consecutive OAM loopback cells an ATM virtual interface must receive to be identified as operational—for example, 200. OAM period—Interval, in seconds, at which OAM cells are transmitted on ATM virtual circuits—for example, 100. The range is between 1 and 900 seconds.	To configure the VPI value, enter set atm-options vpi 25 To configure OAM liveness values on a VPI, enter set atm-options vpi 25 oam-liveness up-count 200 down-count 200 To configure the OAM period, enter set atm-options vpi 25 oam-period 100
Configure the encapsulation type—for example, ethernet-over-atm. atm-pvc—ATM permanent virtual circuits is the default encapsulation for ATM-over-SHDSL interfaces. For PPP over ATM (PPPoA) over SHDSL interfaces, use this type of encapsulation. ethernet-over-atm—Ethernet over ATM encapsulation. For PPP over Ethernet (PPPoE) over ATM-over-SHDSL interfaces that carry IPv4 traffic, use this type of encapsulation.	Enter set encapsulation ethernet-over-atm
Set the annex type. Annex A—Used in North American network implementations. Annex B—Used in European network implementations.	Enter set shdsl-options annex annex-a
Configure the SHDSL line rate for the ATM-over-SHDSL interface–for example, automatic selection of the line rate. The following values are available: auto—Automatically selects a line rate. This option is available only in two-wire mode and is the default value. 192 Kbps or higher—Speed of transmission of data on the SHDSL connection. In the four-wire mode, the default line rate is 4608 Kbps.	Enter set shdsl-options line-rate auto
Configure the loopback option for testing the SHDSL connection integrity–for example, local loopback. The following values are available: local—Used for testing the SHDSL equipment with local network devices. payload—Used to command the remote configuration to send back the received payload. remote—Used to test SHDSL with a remote network configuration.	Enter set shdsl-options loopback local
Configure the signal-to-noise ratio (SNR) margin—for example, 5 dB for either or both of the following thresholds: current—Line trains at higher than current noise margin plus SNR threshold. The range is 0 to 10 dB. The default value is 0. snext—Line trains at higher than self-near-end crosstalk (SNEXT) threshold. The default value is disabled. Setting the SNR creates a more stable SHDSL connection by making the line train at a SNR margin higher than the threshold. If any external noise below the threshold is applied to the line, the line remains stable. You can also disable the SNR margin thresholds.	Enter set shdsl-options snr-margin current 5 Enter set shdsl-options snr-margin snext 5
Configuring Logical Properties
Add the logical interface. Set a value from 0 and 16385—for example, 3. Add other values if required by your network.	Enter set unit 3
Configure encapsulation for the ATM-for-SHDSL logical unit—for example, atm-nlpid. The following encapsulations are supported on the ATM-over-SHDSL interfaces that use inet (IP) protocols only: atm-vc-mux—Use ATM virtual circuit multiplex encapsulation. atm-nlpid—Use ATM network layer protocol identifier (NLPID) encapsulation. atm-cisco-nlpid—Use Cisco NLPID encapsulation. ether-over-atm-llc—For interfaces that carry IPv4 traffic, use Ethernet over LLC encapsulation. You cannot configure multipoint interfaces if you use this type of encapsulation. The following encapsulations are supported on the ATM-over-SHDSL for PPP-over-ATM (PPPoA) interfaces only. atm-ppp-llc—AAL5 logical link control (LLC) encapsulation. atm-ppp-vc-mux—Use AAL5 multiplex encapsulation. Other encapsulation types supported on the ATM-over-SHDSL interfaces: ppp-over-ether-over-atm-llc—Use PPP over Ethernet over ATM LLC encapsulation. When you use this encapsulation type, you cannot configure the interface address. Instead you configure the interface address on the PPP interface. atm-snap—Use ATM subnetwork attachment point (SNAP) encapsulation.	Enter set unit 3 encapsulation atm-nlpid
Configure Operation, Maintenance, and Administration (OAM) options for ATM virtual circuits: OAM F5 loopback cell thresholds (“liveness”) on ATM virtual circuits. The range is between 1 and 255, and the default is 5 cells. Down count—Number of consecutive OAM loopback cells an ATM virtual circuit must lose to be identified as unavailable—for example, 200. Up count—Number of consecutive OAM loopback cells an ATM virtual interface must receive to be identified as operational—for example, 200. OAM period—Interval, in seconds, at which OAM cells are transmitted on ATM virtual circuits—for example, 100. The range is between 1 and 900 seconds.	To configure OAM liveness values for an ATM virtual circuit, enter set unit 3 oam-liveness up-count 200 down-count 200 To configure the OAM period, enter set unit 3 oam-period 100
Add the Family protocol type—for example, inet.	Enter set unit 3 family inet Commands vary depending on the protocol type.
Configure ATM virtual channel identifier (VCI) options for the interface. ATM VCI type—vci. ATM VCI value—A number between 0 and 4089—for example, 35—with VCIs 0 through 31 reserved.	To configure the VCI value, enter set unit 3 vci 35

Task

CLI Configuration Editor

Navigate to the Chassis level in the configuration hierarchy.

From the [edit] hierarchy level, enter

set chassis fpc 6 pic 0 shdsl pic-mode 1-port-atm

Set the ATM-over-SHDSL mode on the G.SHDSL interface, if required. By default, G.SHDSL interfaces are enabled in two-wire Annex B mode. To configure the four-wire mode on the G.SHDSL interface, follow the tasks in this table.

Navigate to the Interfaces level in the configuration hierarchy.

Create the new interface—for example, at-2/0/0.

Configuring Physical Properties

Configure ATM virtual path identifier (VPI) options for the interface—for example, at-2/0/0.

ATM VPI—A number between 0 and 255—for example, 25.
Operation, Maintenance, and Administration (OAM) F5 loopback cell thresholds (“liveness”) on ATM virtual circuits. The range is between 1 and 255, and the default is 5 cells.
- Down count—Number of consecutive OAM loopback cells an ATM virtual circuit must lose to be identified as unavailable—for example, 200.
- Up count—Number of consecutive OAM loopback cells an ATM virtual interface must receive to be identified as operational—for example, 200.
OAM period—Interval, in seconds, at which OAM cells are transmitted on ATM virtual circuits—for example, 100. The range is between 1 and 900 seconds.

To configure the VPI value, enter
set atm-options vpi 25
To configure OAM liveness values on a VPI, enter
set atm-options vpi 25 oam-liveness up-count 200 down-count 200
To configure the OAM period, enter
set atm-options vpi 25 oam-period 100

Configure the encapsulation type—for example, ethernet-over-atm.

atm-pvc—ATM permanent virtual circuits is the default encapsulation for ATM-over-SHDSL interfaces.
For PPP over ATM (PPPoA) over SHDSL interfaces, use this type of encapsulation.
ethernet-over-atm—Ethernet over ATM encapsulation.
For PPP over Ethernet (PPPoE) over ATM-over-SHDSL interfaces that carry IPv4 traffic, use this type of encapsulation.

Enter

set encapsulation ethernet-over-atm

Set the annex type.

Annex A—Used in North American network implementations.
Annex B—Used in European network implementations.

Enter

set shdsl-options annex annex-a

Configure the SHDSL line rate for the ATM-over-SHDSL interface–for example, automatic selection of the line rate.

The following values are available:

auto—Automatically selects a line rate. This option is available only in two-wire mode and is the default value.
192 Kbps or higher—Speed of transmission of data on the SHDSL connection.

In the four-wire mode, the default line rate is 4608 Kbps.

Enter

set shdsl-options line-rate auto

Configure the loopback option for testing the SHDSL connection integrity–for example, local loopback.

The following values are available:

local—Used for testing the SHDSL equipment with local network devices.
payload—Used to command the remote configuration to send back the received payload.
remote—Used to test SHDSL with a remote network configuration.

Enter

set shdsl-options loopback local

Configure the signal-to-noise ratio (SNR) margin—for example, 5 dB for either or both of the following thresholds:

current—Line trains at higher than current noise margin plus SNR threshold. The range is 0 to 10 dB. The default value is 0.
snext—Line trains at higher than self-near-end crosstalk (SNEXT) threshold. The default value is disabled.

Setting the SNR creates a more stable SHDSL connection by making the line train at a SNR margin higher than the threshold. If any external noise below the threshold is applied to the line, the line remains stable. You can also disable the SNR margin thresholds.

Enter
set shdsl-options snr-margin current 5
Enter
set shdsl-options snr-margin snext 5

Configuring Logical Properties

Add the logical interface.

Set a value from 0 and 16385—for example, 3.

Add other values if required by your network.

Enter

set unit 3

Configure encapsulation for the ATM-for-SHDSL logical unit—for example, atm-nlpid.

The following encapsulations are supported on the ATM-over-SHDSL interfaces that use inet (IP) protocols only:

atm-vc-mux—Use ATM virtual circuit multiplex encapsulation.
atm-nlpid—Use ATM network layer protocol identifier (NLPID) encapsulation.
atm-cisco-nlpid—Use Cisco NLPID encapsulation.
ether-over-atm-llc—For interfaces that carry IPv4 traffic, use Ethernet over LLC encapsulation. You cannot configure multipoint interfaces if you use this type of encapsulation.

The following encapsulations are supported on the ATM-over-SHDSL for PPP-over-ATM (PPPoA) interfaces only.

atm-ppp-llc—AAL5 logical link control (LLC) encapsulation.
atm-ppp-vc-mux—Use AAL5 multiplex encapsulation.

Other encapsulation types supported on the ATM-over-SHDSL interfaces:

ppp-over-ether-over-atm-llc—Use PPP over Ethernet over ATM LLC encapsulation. When you use this encapsulation type, you cannot configure the interface address. Instead you configure the interface address on the PPP interface.
atm-snap—Use ATM subnetwork attachment point (SNAP) encapsulation.

Enter

set unit 3 encapsulation atm-nlpid

Configure Operation, Maintenance, and Administration (OAM) options for ATM virtual circuits:

OAM F5 loopback cell thresholds (“liveness”) on ATM virtual circuits. The range is between 1 and 255, and the default is 5 cells.
- Down count—Number of consecutive OAM loopback cells an ATM virtual circuit must lose to be identified as unavailable—for example, 200.
- Up count—Number of consecutive OAM loopback cells an ATM virtual interface must receive to be identified as operational—for example, 200.
OAM period—Interval, in seconds, at which OAM cells are transmitted on ATM virtual circuits—for example, 100. The range is between 1 and 900 seconds.

To configure OAM liveness values for an ATM virtual circuit, enter
set unit 3 oam-liveness up-count 200 down-count 200
To configure the OAM period, enter
set unit 3 oam-period 100

Add the Family protocol type—for example, inet.

Enter

set unit 3 family inet

Commands vary depending on the protocol type.

Configure ATM virtual channel identifier (VCI) options for the interface.

ATM VCI type—vci.
ATM VCI value—A number between 0 and 4089—for example, 35—with VCIs 0 through 31 reserved.

To configure the VCI value, enter
set unit 3 vci 35