SNR S2989G-24TX-UPS — руководство по настройке надежности Ethernet-сетей [432/553]

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S2989G-24TX Operation Manual

Chapter 7 Reliability Configuration

7-33

is that it must be flexible no matter which detection mechanism was used, the link fault

can be found in a short time and it will be noticed to the erps module. The link fault rotating

time that erps asks is: flow discontinuity time is 50ms at most with that the link length is in

1200km and in 16 nodes. It is demanding for the link fault discovery and loop protection

protocol rotating time.

7.5.1.1 ERPS Terminology

Ethernet ring：It is the closed physical ring network which is made up by many ring nodes,

every node on the ring has only two ports connecting to this ring network.

Ring protection link：RPL is a link on the ring network. When the ring network is healthy,

the link blocked by the node cannot transmit the data flow.

RPL owner node：When the ring network is healthy, the nodes connected to RPL will

block the RPL. At the same time, it will launch the link rotating when the ring network

restored and it is configured as reversion.

RPL neighbor node：RPL neighbor node, it is the other node connected to RPL. When

the ring network is healthy, it will block the RPL.

Interconnection node：Cross node, when there are many rings are crossed, it is the node

in the cross position. On the cross nodes, there is one or more rings can be connected

through two ports. The ring connected through one port is the sub-ring, the ring connected

through two ports is the main ring.

R-APS virtual channel：It is the link which makes the sub-ring connect between two

interconnection nodes out of the sub-ring path. Its transmission characteristic is related to

the out ring network.

major-ring：It is the ring which connects the two ports on the interconnection node.

sub-ring：It is the ring which connects to other network through two interconnection nodes.

it is not a ring network, it will make up a ring network only when connect it through the

interconnection node.

ERP instance：It is a set protected by many vlan. The packet transmission of the vlan in

this instance pass the same ring network link, every vlan only belongs to one instance.

Revertive switch：After learning of the ring network fault restored, the RPL owner node

will restore the blockade status of RPL and make the network flow transmission path

restore to the link before the fault.

Non-revertive switch：After learning of the ring network fault restored, the RPL owner

node will not block the RPL, the network flow transmission path is same as before.

7.5.1.2 ERPS Function