4. Web Management
AirLive SNMP-GSH2004L User’s Manual
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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
Port State:
Show the current port state.
