AirLive POE-GSH2004L-370 User Manual
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4. Web Management
RSTP Port Status
Path Cost:
It is the contribution value of the path through this port to Root Bridge. STP algorithm
determines a best path to Root Bridge by calculating the sum of path cost contributed by all
ports on this path. A port with a smaller path cost value would become the Root Port more
possibly.
Edge Port:
If user selects “Yes”, this port will be an edge port. An Edge Port is a port connected to a
device that knows nothing about STP or RSTP. Usually, the connected device is an end
station. Edge Ports will immediately transit to forwarding state and skip the listening and
learning state because the edge ports cannot create bridging loops in the network. This will
expedite the convergence. When the link on the edge port toggles, the STP topology keeps
unchanged. Unlike the designate port or root port though, an edge port will transit to a
normal spanning-tree port immediately if it receives a BPDU.
P2P Port:
We say a port is a point-to-point link, from RSTP’s view, if it is in full-duplex mode but is
shared link if it is in half-duplex mode. RSTP fast convergence can only happen on
point-to-point links and on edge ports. This can expedite the convergence because this will
have the port fast transited to forwarding state. There are three parameters, Auto, True and
False, used to configure the type of the point-to-point link. If configure this parameter to be
Auto, it means RSTP will use the duplex mode resulted from the auto-negotiation. In
today’s switched networks, most links are running in full-duplex mode. For sure, the result
may be half-duplex, in this case, the port will not fast transit to Forwarding state. If it is set
as True, the port is treated as point-to-point link by RSTP and unconditionally transited to
Forwarding state. If it is set as False, fast transition to Forwarding state will not happen on
this port. Default: Auto
Protocol:
Show the root bridge’s spanning tree topology
AirLive POE-GSH2004L-370 User’s Manual
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