Atm Vll (Apipe) Services; Atm Vll For End-To-End Atm Service; Vll Services - Alcatel-Lucent 7705 Service Manual

ATM VLL (Apipe) Services

This section provides information about the Apipe service. Topics in this section include:
Apipe configuration information is found under the following topics:

ATM VLL for End-to-End ATM Service

ATM VLLs (Apipe) provide a point-to-point ATM service between users connected to
7705 SAR nodes or other SR routers over an IP/MPLS network (see
traffic is connected to a 7705 SAR either directly or through an ATM access network. In
both cases, an ATM PVC—for example, a virtual channel (VC) or a virtual path (VP)—is
configured on the 7705 SAR. VPI/VCI translation is supported in the ATM VLL.
The 7705 SAR receives standard UNI/NNI cells on the ATM service access point (SAP),
which are then encapsulated into a pseudowire packet using N-to-1 cell mode encapsulation
in accordance with RFC 4717.
The ATM pseudowire (PW) is initiated using targeted LDP signaling as specified in
RFC 4447, Pseudowire Setup and Maintenance using LDP; alternatively, it can be
configured manually. The 7705 SAR supports MPLS, GRE, and IP as the tunneling
technologies for transporting ATM PWs.
In addition to supporting N-to-1 cell mode encapsulation, ATM VLL service supports cell
concatenation, control word (CW), SAP-to-SAP (local service), and SAP-to-SDP binding
(distributed service). See
information on N-to-1 cell mode encapsulation.
ATM VLL optimizes the ATM cell from a 53-byte cell to a 52-byte packet by removing the
header error control (HEC) byte at the near end. The far end regenerates the HEC before
switching ATM traffic to the attached circuit.
7705 SAR OS Services Guide
• ATM VLL for End-to-End ATM Service
• ATM SAP-to-SAP Service
• ATM Traffic Management Support
• Control Word
• Common Configuration Tasks on page 198
• Configuring VLL Components on page 199
→
Creating an Apipe Service on page 200
• Service Management Tasks on page 221
SAP Encapsulations and Pseudowire Types on page 182

VLL Services

Figure 19). User ATM
for more
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