About AQ-200 series units and RSTP.

About AQ-200 series units and RSTP.

AQ-200 series devices don’t implement any support for the RSTP-protocol. They should be always treated as non-RSTP devices.

That being said, under certain circumstances, it is possible to mix RSTP and non-RSTP devices. For example, the so-called “RSTP ring” (a configuration where two RSTP-switches and several non-RSTP devices are connected into a single loop) should be able to operate although in my understanding this isn’t the application intended by the standard. Also, one needs to be extremely careful when mixing RSTP and non-RSTP devices as it is very easy to cause unintended and unresolved loops or unintentionally inactive links when the complexity of the network increases.

It should also be noted that RSTP really isn’t even intended to be used as a high-availability redundancy network protocol. RSTP should be used only to safeguard the network against unintended loops. For proper redundancy, for example HSR or PRP should be used instead.

RSTP and GOOSE

RSTP should not be used for time critical GOOSE messaging. If GOOSE messages must be used, PRP and HSR protocols should be used instead.

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