Juniper JUNOSE, Руководство по настройке

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The router passes the following OAM cells transparently:
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F5 alarm indication signal (AIS) segment and end-to-end
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F5 remote defect indication (RDI) segment and end-to-end
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F5 loopback segment and end-to-end
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Resource management
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F5 continuity check segment and end-to-end
In addition, F4 OAM cell forwarding is supported.
JUNOSe software does not allow for setting a segment endpoint on an ATM
cross-connect interface. Segment OAM cells are forwarded to the egress interface in
the same manner as end-to-end cells.
QoS Classification
Packets are subject to normal quality of service (QoS) classification according to
service categories assigned to ATM virtual circuits that make up the connection.
Limitations
The JUNOSe implementation of the Martini draft has the following limitations:
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Only AAL5 packets and OAM cells are forwarded.
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There is no equivalent of VP switching.
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Point-to-multipoint connections are not supported.
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Automatic connection setup using user-to-network interface (UNI) signaling and
private network-to-network interface (PNNI) is not supported.
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The ATM MIB cross-connected table is not supported.
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Connections between ATM circuits and non-ATM interfaces are not supported.
Control Word Support
Martini draft encapsulation includes a control word with the following fields:
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T bit for transport type
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E bit for explicit forward congestion indication (EFCI)
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C bit for cell loss priority (CLP)=1 indication
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U bit for command/response indication based on AAL5 common part convergence
sublayer user-to-user indication (CPCS-UU)
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Optional sequence number
The current JUNOSe implementation supports the T bit and optional sequence number
fields.
ATM Layer 2 Services over MPLS
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Chapter 6: Layer 2 Services over MPLS Overview