Requirements, Overview and topology – Juniper Networks JUNOS OS 10.4 User Manual
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traffic to pass through one path while other traffic can follow a different one. Dividing
traffic in this way supports traffic load-balancing in the ring.
This example describes how to use ERP with ring instances to load-balance traffic while
still providing network protection from link failure:
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•
Overview and Topology on page 161
•
•
Requirements
This example uses the following hardware and software components:
•
Two MX Series routers acting as core switches
•
One MX Series router acting as an aggregation switch
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Junos OS Release 10.2 or later for MX Series routers
Overview and Topology
displays the topology for this example. The topology contains three
MX Series routers. CS1 and CS2 act as core routers in the topology, and AS1 acts as an
aggregation switch. Each router has two ring instances, ring-1 and ring-2. All nodes on
the ring coordinate protection activities by exchanging messages through the Ethernet
ring automatic protection switching (R-APS) messaging protocol. Each ring instance has
an RPL owner. The ring-1 RPL owner is CS1; the ring-2 RPL owner is CS2. The RPL owners
block or unblock the RPL as conditions require and initiate R-APS messages.
Each ring instance has two interface ports (an east interface and a west interface) that
participate in the instance. Interface
ge-2/0/8.0
, the west interface on CS2, is the ring
protection link end where ring-2’s RPL terminates. Interface
ge-3/2/4.0
, the east interface
on CS1, is the ring protection link end where ring-1’s RPL terminates.
Each ring instance has a data channel. A data channel is a group of bridge domain virtual
LAN (VLAN) IDs. All VLAN IDs within the same ring interface share the same
data-forwarding properties controlled by the ERP. The data channel on ring-1 is [200,
300]. The data channel on ring-2 is [500, 600].
Two customer site switches are connected to AS1. Customer site 1 uses VLANs 200 and
300. Customer site 2 uses VLANs 500 and 600.
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Copyright © 2013, Juniper Networks, Inc.
Chapter 13: Ethernet Ring Protection