Configuring TDM PWE3
You can configure TDM PWE3 to encapsulate TDM service data and transparently transmit the data through PWs to implement TDM service transmission through PWE3.
Pre-configuration Tasks
Before configuring TDM PWE3, complete the following tasks:
Configuring an IGP protocol on the Ps and PEs on the MPLS backbone network to implement IP connectivity
Configuring basic MPLS capabilities on the backbone network
Installing a 8SA, 6E&M, 8E1T1-M, or 8E1T1-F interface card on the device and ensuring that it is registered successfully
Setting up a tunnel (GRE tunnel, LSP tunnel, or TE tunnel) between the PEs
You also need to configure tunnel policies when PWE3 services need to be transmitted over TE tunnels or when PWE3 services need to be load balanced among multiple tunnels to fully use network resources. For details, see step 1 in Configuring and Applying a Tunnel Policy.
NOTE: Only the AR2204XE, AR2204XE-DC, AR2220, AR2240 (using SRU40, SRU60, SRU80, SRU200, SRU200E, SRU400), AR3200 (using SRU40, SRU60, SRU80, SRU200, SRU200E, SRU400), and AR3600 (using SRUX5) series routers support this function.
Configuring an AC Interface to Transparently Transmit TDM Cells
Context
You can configure an AC interface to transparently transmit TDM cells, so that after receiving TDM packets, the AC interface encapsulates the packets and transmits the packets through a PW.
Perform the following operations on the PEs.
Procedure
- Use either of the following methods to configure AC interface parameters based on the interface card type:
- 8SA interface card: Configure interface parameters such as a working mode for serial interfaces. Ensure that the parameters are the same as those of a CE's interface connected to the AC interface.
![]()
NOTE: For the detailed configuration of a serial interface, see Configuring a Synchronous Serial Interface in Huawei AR Series Access Routers Configuration Guide - Interface Management.
- 6E&M interface card: Configure interface parameters for E&M interfaces. Ensure that the parameters are the same as those of a CE's interface connected to the AC interface.
![]()
NOTE: For the detailed configuration of an E&M interface, see Configuring Line Attributes for an E&M Interface in Huawei AR Series Access Routers Configuration Guide - Interface Management.
- 8E1T1-M interface card: Configure interface parameters such as a working mode for CE1/PRI interfaces. Ensure that the parameters are the same as those of a CE's interface connected to the AC interface. To ensure that CEs exchange data successfully,
the AC interfaces must work in clock synchronization state.
![]()
NOTE: For the detailed configuration of a CE1/PRI interface, see Configuring CE1/PRI Interface in Huawei AR Series Access Routers Configuration Guide - Interface Management.
- 8E1T1-F interface card: Configure interface parameters such as a working mode for E1-F interfaces. Ensure that the parameters are the same as those of a CE's interface connected to the AC interface. To ensure that CEs exchange data successfully,
the AC interfaces must work in clock synchronization state.
![]()
NOTE: For the detailed configuration of an E1-F interface, see Configuring E1-F Interface in Huawei AR Series Access Routers Configuration Guide - Interface Management.
- 8SA interface card: Configure interface parameters such as a working mode for serial interfaces. Ensure that the parameters are the same as those of a CE's interface connected to the AC interface.
- Configure the AC interface to transparently transmit TDM cells.
(Optional) Creating a PW Template and Setting Attributes for the PW Template
Context
A PW template defines common attributes for PWs, so it can be shared by different PWs. The PW template simplifies PW configuration. You can use the PW template to create a PW on an interface.
On the device, the PW can be bound to a PW template and can be reset.
You can set the attributes for a PW through commands or a PW template. The attributes include the peer, tunnel policy, and control word. Importing the PW template can simplify the configuration of PWs with similar attributes.
NOTE: Some PW attributes such as the MTU, PW type, and encapsulation type are obtained from the interface connecting the PE to the CE.
If you specify a PW attribute through commands, the same PW attribute specified in the PW template does not function on the PW to which this PW template is applied.
Perform the following steps on the PE devices.
Procedure
- Run system-view
The system view is displayed.
- Run pw-template pw-template-name
A PW template is created and the PW template view is displayed.
- Run peer-address ip-address
The remote device IP address of the PW is specified.
- Run control-word
The control word function is enabled.
By default, the control word function is disabled.
To enable VCCV in control word mode, enable the control word function only on the UPE for dynamic single-hop PWs, dynamic multi-hop PWs, and static single-hop PWs; enable the control word function on both the UPE and SPE for static multi-hop PWs and mixed dynamic multi-hop PWs.
- Run mtu mtu-value
The MTU in the PW template is specified.
By default, the MTU in a PW template is 1500.
- Run jitter-buffer depth depth
The jitter buffer depth is configured.
By default, the jitter buffer depth is 8 ms.
The jitter buffer is used to reduce jitter at the network side. A larger jitter buffer depth indicates a stronger anti-jitter capability. However, when a long transmission delay is introduced when data flows are reconstructed, improper jitter buffer depth degrades transmission quality.
- Run tdm-encapsulation-number number
The number of encapsulated TDM frames in Circuit Emulation Services over Packet Switch Network (CESoPSN) or Structure-Agnostic Time Division Multiplexing over Packet (SAToP) packets in the TDMoPSN application is set.
By default, the number of encapsulated TDM frames in a CESoPSN or SAToP packet is 8. When the interface card where the AC interface locates is 8SA, 8E1T1-M or 8E1T1-F, the interface can encapsulate a maximum of 16 TDM frames in a packet. If the value is larger than 16, the interface only encapsulates 16 TDM frames in a packet.
You can determine the number of TDM frames encapsulated into each PW packet. The smaller the number of frames encapsulated into a packet, the shorter the encapsulation and transmission delay but the more the encapsulation overhead. The larger the number of frames encapsulated into a packet, the higher the bandwidth utilization but the longer the encapsulation delay.
- Run idle-code idle-code-value
The device is configured to fill idle codes when a jitter buffer underflow occurs.
By default, the system fills idle codes to FF.
A jitter buffer underflow occurs when the device needs to read packets but there are not sufficient packets in the buffer. The idle code has no significance, and can be set to any value.
- Run tnl-policy policy-name
A tunnel policy is configured for the PW.
Configure a tunnel policy before you can apply this policy. If no tunnel policy is configured, an LSP tunnel is used and load balancing is not implemented. For details on the tunnel policy configuration, see step 1 in Configuring and Applying a Tunnel Policy.
Configuring PW
Procedure
- Run system-view
The system view is displayed.
- Run interface serial interface-number
The serial interface view is displayed.
- Configure PWE3 function.
Choose either of them based on the networking.
- Configure a static PW.
To configure an active PW, run:
mpls static-l2vc { { destination ip-address | pw-template pw-template-name vc-id } * | destination ip-address [ vc-id ] } transmit-vpn-label transmit-label-value receive-vpn-label receive-label-value [ tunnel-policy tnl-policy-name | [ control-word | no-control-word ] | idle-code idle-code-value | jitter-buffer depth | tdm-encapsulation number | tdm-sequence-number ] *
(Optional) To configure a standby PW, run:
mpls static-l2vc { { destination ip-address | pw-template pw-template-name vc-id } * | destination ip-address [ vc-id ] } transmit-vpn-label transmit-label-value receive-vpn-label receive-label-value [ tunnel-policy tnl-policy-name | [ control-word | no-control-word ] | idle-code idle-code-value | jitter-buffer depth | tdm-encapsulation number | tdm-sequence-number ] * secondary
![]()
NOTE: You can configure a standby PW only after an active PW is configured.
The combination of the PW ID and PW type must be unique on each node. The IDs of PWs on two ends can be the same. Active and standby PWs must have different VC IDs.
Active and standby PWs must use the same control word configuration; otherwise, many packets may be lost during service switching.
- Configure a dynamic PW
To configure an active PW, run:
mpls l2vc { ip-address | pw-template pw-template-name } * vc-id [ tunnel-policy policy-name | [ control-word | no-control-word ] | mtu mtu-value | idle-code idle-code-value | jitter-buffer depth | tdm-encapsulation-number number | tdm-sequence-number ] *
(Optional) To configure a standby PW, run:
mpls l2vc { ip-address | pw-template pw-template-name } * vc-id [ tunnel-policy policy-name | [ control-word | no-control-word ] | mtu mtu-value | idle-code idle-code-value | jitter-buffer depth | tdm-encapsulation-number number | tdm-sequence-number ] * secondary
![]()
NOTE: A dynamic PW requires that the VC ID of the same encapsulation type on a PE be unique. Changing the encapsulation type may cause a VC ID collision.
You can configure a standby PW only after an active PW is configured.
The combination of the PW ID and PW type must be unique on each node. The IDs of PWs on two ends can be the same. Active and standby PWs must have different VC IDs.
Active and standby PWs must use the same control word configuration; otherwise, many packets may be lost during service switching.
- Configuring PW Switching
Perform this operation on the SPE only. Select static PW or dynamic PW based on the PW switching mode on the UPE.
PW switching is classified into static mode, dynamic mode, and mixed mode:
- When static PWs are used between the SPE and two connected PEs, configure static PW switching.
- When dynamic PWs are used between the SPE and two connected PEs, configure dynamic PW switching.
- When a static PW and a dynamic PW are used between the SPE and two connected PEs, configure mixed PW switching.
Perform either of the following operations based on actual needs.
To configuring a static PW switching, run:
mpls switch-l2vc ip-address vc-id trans trans-label recv received-label [ tunnel-policy policy-name ] between ip-address vc-id trans trans-label recv received-label [ tunnel-policy policy-name ] encapsulation encapsulation-type [ control-word [ cc { alert | cw } * cv lsp-ping ] | [ no-control-word ] [ cc alert cv lsp-ping ] ] [ control-word-transparent ]
![]()
NOTE: When different PW encapsulation modes are selected, the parameters to be specified are as follows:
- If encapsulation-type is set to satop-e1, the following parameters can be specified: [no-control-word ] [ cc alert cv lsp-ping ].
If encapsulation-type is set to cesopsn-basic, the following parameters can be specified: control-word [ cc { alert | cw } * cv lsp-ping ], [no-control-word ] [ cc alert cv lsp-ping ].
The timeslotnum timeslotnum needs to be configured.
To configuring a dynamic PW switching, run:
mpls switch-l2vc ip-address vc-id [ tunnel-policy policy-name ] between ip-address vc-id [ tunnel-policy policy-name ] encapsulation encapsulation-type [ control-word-transparent ]
To configuring a mixed PW switching, run:
mpls switch-l2vc ip-address vc-id [ tunnel-policy policy-name ] between ip-address vc-id trans trans-label recv received-label [ tunnel-policy policy-name ] encapsulation encapsulation-type [ mtu mtu-value ] [ control-word | no-control-word ] [ timeslotnum timeslotnum ] [ tdm-encapsulation number ] [ control-word-transparent ]
![]()
NOTE: When you configure mixed PW switching, ip-address vc-id before between specifies the VC ID of a dynamic PW and ip-address vc-id after between specifies the VC ID of a static PW. The two values cannot be interchanged.
In mixed PW switching, the MTUs of the interfaces on the two ends must be the same and cannot be greater than 1500 bytes.
When different PW encapsulation modes are selected, the parameters to be specified are as follows:
- If encapsulation-type is set to satop-e1, the following parameters can be specified: mtu mtu-value, control-word, no-control-word, and tdm-encapsulation number.
If encapsulation-type is set to cesopsn-basic, the following parameters can be specified: mtu mtu-value, control-word, no-control-word, timeslotnum timeslotnum, and tdm-encapsulation number.
The timeslotnum timeslotnum needs to be configured.
- Configure a static PW.
- (Optional) Run mpls l2vpn pw performance disable
The statistics collection function for PWs on the TDM interface is disabled.
After PW is configured on a TDM interface, the statistics collection function for PWs on the TDM interface is enabled by default. The system collects statistics on sent and received packets of the primary PW at an interval of 15 minutes. To improve statistics collection efficiency for system performance or other performance, you can perform this step to disable the statistics collection function for PWs on the TDM interface.
Verifying the TDM PWE3 Configuration
Prerequisites
The configurations of the TDM PWE3 are complete.
NOTE: After a PW with the encapsulation type being TDM is configured on the AC side, PW performance statistics collection is enabled on the related TDM interface by default. Run the undo mpls l2vpn pw performance disable command can enable the function of PW performance information collection on a TDM interface.
Procedure
- Run the display pw-template [ pw-template-name ] command to check information about the PW template.
- Run the display mpls static-l2vc [ vc-id | interface interface-type interface-number | state { down | up } ] command to check the information about static VCs.
- Run the display mpls l2vc [ vc-id | interface interface-type interface-number | remote-info [ vc-id | verbose ] | state { down | up } ] command to check the information about virtual circuits in LDP mode.
- Run the display mpls switch-l2vc [ ip-address vc-id encapsulation encapsulation-type | state { down | up } ] command on the SPE to view information about PW switching.
- Run the display tunnel-info { tunnel-id tunnel-id | all | statistics [ slots ] } command to check information about tunnels in the system.
- Run the display tunnel-policy [ tunnel-policy-name ] command to check information about the specified tunnel policy.
- Run the display mpls l2vpn interface interface-type interface-number performance command to check PW performance information on a TDM interface.
Previous
