Chapter 13
| Basic Administration Protocols
Ethernet Ring Protection Switching
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Figure 293: Managing a Cluster Member
Ethernet Ring Protection Switching
Note:
Information in this section is based on ITU-T G.8032/Y.1344.
The ITU G.8032 recommendation specifies a protection switching mechanism and
protocol for Ethernet layer network rings. Ethernet rings can provide wide-area
multipoint connectivity more economically due to their reduced number of links.
The mechanisms and protocol defined in G.8032 achieve highly reliable and stable
protection; and never form loops, which would fatally affect network operation and
service availability.
The G.8032 recommendation, also referred to as Ethernet Ring Protection
Switching (ERPS), can be used to increase the availability and robustness of
Ethernet rings. An Ethernet ring built using ERPS can provide resilience at a lower
cost and than that provided by SONET or EAPS rings.
ERPS is more economical than EAPS in that only one physical link is required
between each node in the ring. However, since it can tolerate only one break in the
ring, it is not as robust as EAPS. ERPS supports up to 255 nodes in the ring structure.
ERPS requires a higher convergence time when more that 16 nodes are used, but
should always run under than 500 ms.
Operational Concept
Loop avoidance in the ring is achieved by guaranteeing that, at any time, traffic
may flow on all but one of the ring links. This particular link is called the ring
protection link (RPL), and under normal conditions this link is blocked to traffic. One
designated node, the RPL owner, is responsible for blocking traffic over the RPL.
When a ring failure occurs, the RPL owner is responsible for unblocking the RPL,
allowing this link to be used for traffic.
Ring nodes may be in one of two states:
Idle – normal operation, no link/node faults detected in ring
Protection – Protection switching in effect after identifying a signal fault
Содержание GTL-2881
Страница 30: ...Figures 30 Figure 450 Showing RIP Peer Information 669 Figure 451 Resetting RIP Statistics 670 ...
Страница 34: ...Section I Getting Started 34 ...
Страница 48: ...Section II Web Configuration 48 Unicast Routing on page 651 ...
Страница 151: ...Chapter 4 Interface Configuration VLAN Trunking 151 Figure 69 Configuring VLAN Trunking ...
Страница 152: ...Chapter 4 Interface Configuration VLAN Trunking 152 ...
Страница 229: ...Chapter 8 Congestion Control Automatic Traffic Control 229 Figure 135 Configuring ATC Interface Attributes ...
Страница 230: ...Chapter 8 Congestion Control Automatic Traffic Control 230 ...
Страница 596: ...Chapter 14 Multicast Filtering Multicast VLAN Registration for IPv6 596 ...
Страница 620: ...Chapter 15 IP Configuration Setting the Switch s IP Address IP Version 6 620 ...
Страница 670: ...Chapter 18 Unicast Routing Configuring the Routing Information Protocol 670 Figure 451 Resetting RIP Statistics ...
Страница 672: ...Section III Appendices 672 ...
Страница 678: ...Appendix A Software Specifications Management Information Bases 678 ...
Страница 688: ...Appendix C License Statement GPL Code Statement Notification of Compliance 688 ...
Страница 696: ...Glossary 696 ...
Страница 706: ...GTL 2881 GTL 2882 E112016 ST R01 ...