Cisco Catalyst 3750 Metro Switch DC Power Supply (spare) PWR-ME3750-DC= Data Sheet
Product codes
PWR-ME3750-DC=
Data Sheet
© 2008 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.
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The Cisco Catalyst 3750 Metro Series supports an intelligent enhanced version of 802.1Q
tunneling in which the enterprise customer’s Layer 2 or Layer 3 QoS information can be mapped
from the inner VLAN tag to the outer service provider VLAN tag. As a result, the enterprise
customer’s QoS priorities are used across the service provider’s network. In addition, the Cisco
Catalyst 3750 Metro Series supports Selective QinQ whereby the switch can assign a service
provider VLAN tag to the customer traffic based on the ingress interface and customer’s VLAN ID.
Layer 2 VPN Using VLAN Translation
VLAN translation is also used for Layer 2 VPN service. Instead of double-tagging the packet, the
VLAN translation feature simply translates a customer VLAN ID to a service provider VLAN ID as
the packet enters the service provider network, and vice versa as the packet exits the service
provider network. By simply mapping the VLAN ID and leaving the rest of the packet untouched,
the enterprise customer’s QoS information can be preserved and honored as it traverses the
service provider network.
Layer 2 VPN Using EoMPLS
EoMPLS is a tunneling mechanism that allows service providers to tunnel customer Layer 2 traffic
through a Layer 3 MPLS network. This gives the service provider the best of both worlds—a Layer
2 TLS offering and the scalability of an MPLS core without needing a spanning tree. The Cisco
Catalyst 3750 Metro Series supports EoMPLS on a per-port or per-VLAN basis, enabling service
providers to build an end-to-end MPLS network all the way to the CLE.
Layer 2 VPN with H-VPLS Architecture
VPLS is a multipoint Layer 2 VPN technology that allows multiple sites to be connected over a
simulated Ethernet broadcast domain that is supported across a provider-provisioned MPLS
network. H-VPLS is one of IETF’s VPLS standards that provides an MPLS-based distributed-PE
architecture. H-VPLS has two design options:
●
Ethernet access network: Access networks are 802.1Q networks, and the core network is
MPLS.
●
MPLS access network: Access networks and the core network are both MPLS.
The Cisco Catalyst 3750 Metro Series supports both architecture options as the PE-CLE switch in
the H-VPLS access network.
Layer 3 VPN Using Multi-VRF CE
Multi–Virtual Routing and Forwarding Customer Edge (Multi-VRF CE), also called VRF-lite, on the
Cisco Catalyst 3750 Metro Series enables the creation of a Layer 3 VPN service by keeping
separate routing tables for each VPN customer without needing to run MPLS on the switch. Multi-
VRF CE is a feature that allows a service provider to support two or more VPNs on a single Cisco
Catalyst 3750 Metro Series switch, where IP addresses can be overlapped among the VPNs.
Multi-VRF CE uses input interfaces to distinguish routes for different VPNs and forms virtual
packet-forwarding tables by associating one or more Layer 3 interfaces with each VRF.
Layer 3 VPN Using MPLS VPN
The Cisco Catalyst 3570 Metro Series supports MPLS VPNs, allowing service providers to build
true end-to-end MPLS networks and to offer MPLS VPN services to their enterprise and
commercial customers. The MPLS VPN model is a true peer VPN model that enforces traffic
separations by assigning unique VRFs to each customer’s VPN. Thus, users in a specific VPN