Juniper JUNOSE, Configuration Manual

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Chapter 6
Layer 2 Services over MPLS Overview
This chapter contains the following sections:
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Layer 2 Services over MPLS Overview on page 503
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Layer 2 Services over MPLS Platform Considerations on page 504
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Layer 2 Services over MPLS References on page 505
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Layer 2 Services over MPLS Implementation on page 506
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Local Cross-Connects Between Layer 2 Interfaces Using MPLS on page 507
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MPLS Shim Interfaces for Layer 2 Services over MPLS on page 507
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Multiple Layer 2 Services over MPLS on page 509
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ATM Layer 2 Services over MPLS on page 509
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HDLC Layer 2 Services over MPLS on page 513
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CE-Side MPLS L2VPNs over LAG Overview on page 515
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Ethernet Raw Mode Encapsulation for Martini Layer 2 Transport
Overview on page 516
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S-VLAN Subinterface with an Untagged C-VLAN ID Overview on page 518
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Multiple ATM Virtual Circuits over a Single Pseudowire Overview on page 518
Layer 2 Services over MPLS Overview
Many Internet service providers offer multiple services such as Frame Relay,
Asynchronous Transfer Mode (ATM), Ethernet, High-Speed Data Link Control (HDLC),
and IP to their customers, but are consolidating to a single, packet-based, optical
network from several service-specific legacy layer 2 networks. Although legacy layer
2 network links are disappearing from the Internet service provider’s network, the
legacy layer 2 network links and services to customers must remain.
Layer 2 services over IP/MPLS enable service providers to emulate the legacy layer
2 network links and services over their IP/MPLS-based network. Layer 2 services
over MPLS are especially desirable because MPLS provides features such as traffic
engineering and fast reroute. These MPLS features can be used to emulate certain
layer 2 service characteristics. From the perspective of the customer edge (CE) devices,
all that exists is the layer 2 circuit, even though the circuit actually exists over the
service provider’s MPLS network.
The JUNOSe software currently support the following layer 2 services over MPLS:
Layer 2 Services over MPLS Overview
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