Web Management Guide-R01

Table Of Contents
Chapter 13
| Basic Administration Protocols
Ethernet Ring Protection Switching
– 486 –
Figure 314: Sub-ring without Virtual Channel
R-APS Def MAC – Sets the switchs MAC address to be used as the node
identifier in R-APS messages. (Default: Enabled)
When ring nodes running ERPSv1 and ERPSv2 co-exist on the same ring, the
Ring ID of each ring node must be configured as “1”.
If this command is disabled, the following strings are used as the node
identifier:
ERPSv1: 01-19-A7-00-00-01
ERPSv2: 01-19-A7-00-00-[Ring ID]
Propagate TC – Enables propagation of topology change messages from a
secondary ring to the primary ring. (Default: Disabled)
When a secondary ring detects a topology change, it can pass a message about
this event to the major ring. When the major ring receives this kind of message
from a secondary ring, it can clear the MAC addresses on its ring ports to help
the second ay ring restore its connections more quickly through protection
switching.
When the MAC addresses are cleared, data traffic may flood onto the major
ring. The data traffic will become stable after the MAC addresses are learned
again. The major ring will not be broken, but the bandwidth of data traffic on
the major ring may suffer for a short period of time due to this flooding
behavior.
Holdoff Timer – The hold-off timer is used to filter out intermittent link faults.
Faults will only be reported to the ring protection mechanism if this timer
expires. (Range: 0-10000 milliseconds, in steps of 100 milliseconds)
In order to coordinate timing of protection switches at multiple layers, a hold-
off timer may be required. Its purpose is to allow, for example, a server layer
protection switch to have a chance to fix the problem before switching at a
client layer.
When a new defect or more severe defect occurs (new Signal Failure), this event
will not be reported immediately to the protection switching mechanism if the
provisioned hold-off timer value is non-zero. Instead, the hold-off timer will be
started. When the timer expires, whether a defect still exists or not, the timer
will be checked. If one does exist, that defect will be reported to the protection
Sub-ring
with Virtual
Channel
RPL Port
Interconnection Node
Ring Node
Major Ring