OVERVIEW
DOC_DE_User guide_B
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Proprietary failsafe ring algorithm:
Based on the STP algorithm, that solution makes possible to handle a ring structure up to 16 SHSDL switches.
The advantages of that solution is that the failure detection delay and the recovery delay is only a few seconds
(One second if the ring counts 5 SHDSL switches); moreover, it is very simple to configure.
5.3
The by-pass function
When the network is a daisy chain
–
that case is very frequent in industrial applications - and when, however,
it is not possible to build a failsafe structure like a ring, the XSLAN+BP offers a very useful function called the
“By
-
pass function”.
The XSLAN+BP includes an electro-mechanical relay between both lines; that relay is automatically closed to
connect the two lines when the XSLAN+BP is switched off.
For instance, if the XSLAN+ #2 cabinet is switched off
for maintenance, the by-pass relay inside the XSLAN+
#2 will automatically connect the line coming from the
XSLAN+ #1 to the line going to the XSLAN+ #3.
After a few seconds, the XSLAN+ #1 detects the
connection default and establishes immediately the
connection with the XSLAN+ #3.
5.4
The loop VPN function
When the SHDSL network forms a daisy chain (ie a linear topology), and when it is not possible to form a
secure ring, the "loop VPN" function allows for network redundancy if a public WAN connection (Internet) or
private (MPLS) is available at each end of the SHDSL network.
