Juniper JUNOSE, Configuration Manual

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the router does not enable opening of the VP-level OAM circuits to be transported
transparently on the pseudowire. Because only a subset of the ATM virtual circuits
on an ATM port are carried on the pseudowire, LDP uses the ATM n-to-one VCC cell
transport (0x0009) pseudowire (PW) type instead of the ATM transparent cell transport
(0x0003) PW type in the signaling messages.
Guidelines for Configuring VPI/VCI Ranges of ATM Virtual Circuits
Observe the following guidelines when you specify a single VPI/VCI range of ATM
VCs whose cells need to be transported on the single pseudowire:
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Use to specify a single VPI/VCI range of ATM VCs whose cells need to be
transported on the single pseudowire.
■
You can configure the mpls-relay atm vpi-range vci-range command on the
ATM port only after you associated a pseudowire with the port by using the
mpls-relay or route interface tunnel command.
■
You can use this command only on an ATM port (ATM AAL5 over ATM major
interface). When you attempt to run this command on other interface types,
such as ATM subinterfaces or Ethernet interfaces, this setting is not saved and
an error message is displayed.
■
When you run the mpls-relay or route interface tunnel command, no default
VPI/VCI range is configured. You must specifically configure the VPI/VCI ranges.
■
The VPI/VCI values that are not part of the specified range can be used for other
existing applications. For example, you can configure an ATM subinterface on
the same ATM port with a VPI/VCI value that is not included by the specified
range specification and use that interface as an IP interface or subscriber interface.
■
If you configured a VPI/VCI range on the shim interface and try to configure an
ATM subinterface with the VPI/VCI value that is encompassed by the VPI/VCI
range specified earlier on the shim interface, an error message is displayed
stating the VPI/VICI range that you are trying to configure is already reserved
and the configuration fails.
■
If some of the VPI/VCI values specified in the range are used for other applications,
the specified range is marked inactive and this setting is saved on the router,
without being used to transport traffic. You must remove the conflicting range,
and remove or reconfigure this range to activate it for transportation of ATM
cells.
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If the specified VPI/VCI range includes the F4 OAM VCI values, the range is saved.
The F4 OAM VCs are not opened, but the rest of the VCs are opened if they are
not configured for other applications. If some of the VCs other than the F4 OAM
VCs are opened for other applications, the range is marked inactive. You must
specify ranges that do not overlap with the F4 OAM VCI values.
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You can specify up to four non-overlapping VPI/VCI ranges on the ATM port that
has been associated with the single pseudowire using the
mpls-relay or router
interface tunnel command.
■
When a VPI/VCI range that you enter overlaps with already specified ranges, the
newly specified range becomes effective.
Multiple ATM Virtual Circuits over a Single Pseudowire Overview
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Chapter 6: Layer 2 Services over MPLS Overview