DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet User Manual
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Figure 4- 84 ERPS Settings (Edit) window
The following parameters may be configured after the
Edit
button has been clicked on the window above:
Parameter Description
Ring Status
Tick the check box and toggle between
Enabled
and
Disabled
to enable or disable the ERPS
State.
West Port
Tick the check box and select the desired west ring port between
01
and
12
. ERPS uses
cardinal direction terms “East” and “West” to designate how the ports on nodes in the ring are
oriented to the ring itself. Each node on the ring has an East port and West port. The West
port of one node is linked to the East port of the adjacent node in the ring. Alternatively, users
can select
Virtual Channel
to specify the port as a west port on a virtual channel.
East Port
Tick the check box and select the desired east ring port between
01
and
12.
ERPS uses
cardinal direction terms “East” and “West” to designate how the ports on nodes in the ring are
oriented to the ring itself. Each node on the ring has an East port and West port. The West
port of one node is linked to the East port of the adjacent node in the ring. Alternatively, users
can select
Virtual Channel
to specify the port as a east port on a virtual channel.
RPL Port
Tick the check box and select the desired RPL Port,
West Port
,
East Port
, or
None
. This
specifies the ring port as the Ring Protection Link (RPL) port. The RPL remains idle and
blocks traffic when all links on the ring are functioning. If there is a link failure on the ring
however, the RPL port is unblocked by the RPL Owner node in order to allow an alternate
path around the ring.
RPL Owner
Tick the check box and toggle between
Enabled
and
Disabled
to enable or disable the device
as an RPL owner node. This node blocks or unblocks the RPL as required by network
conditions. An Ethernet Ring Automatic Protection Switching (R-APS) message protocol
coordinates protection activities for all nodes on the ring. In the event of a link failure, the RPL
Owner uses these messages to block a failed link and unblock the RPL. There can be only
one RPL Owner on a ring.
Protected VLAN(s)
(e.g.: 4-6)
Tick the check box, enter the VLANs that are protected by the ERPS function, and then click
Add or Delete.
Ring MEL (0-7)
Tick the check box and enter the ring Maintenance Entity Group (MEG) level (MEL) of the R-
APS function.
Hold Off Time (0-
10000)
Tick the check box and enter the hold off time of the R-APS function. A hold off timer is used
in order to coordinate timing of ERPS at multiple levels. The purpose is to allow, for example,
a server layer switch to be able to fix the problem before switching at a client layer.
When a new defect or more sever defect is detected, the event will not be reported
immediately, instead, after the hold off timer expires, the trail that started the timer will be
checked to see if the defect still exists. If it exists, the defect is reported and the ERPS goes
into effect.
Guard Time (10-
2000)
Tick the check box and enter the guard time of the R-APS function. While the Guard timer is
running, received R-APS messages are not forwarded to the RPL Owner. The purpose of this
