NEC N8406-022 manual •Port number and priority •Cost •State •Role, •Link type and port type

You can also refer to the following port-specific CIST information:

•Port number and priority

•Cost

•State

•Role

•Designated bridge and port

•Hello interval

•Link type and port type

The following table describes the CIST parameters.

Table 21 Common Internal Spanning Tree parameter descriptions

Parameter	Description
CIST Root	Shows information about the root bridge for the Common Internal Spanning Tree
	(CIST). Values on this row of information refer to the CIST root.
CIST Regional Root	Shows information about the root bridge for this MSTP region. Values on this row
	of information refer to the regional root.
Priority (bridge)	The bridge priority parameter controls which bridge on the network will become
	the STP root bridge.
MaxAge	The maximum age parameter specifies, in seconds, the maximum time the bridge
	waits without receiving a configuration bridge protocol data unit before it
	reconfigures the STP network.
FwdDel	The forward delay parameter specifies, in seconds, the amount of time that a
	bridge port has to wait before it changes from learning state to forwarding state.
Hops	Shows the maximum number of bridge hops allowed before a packet is dropped.
Priority (port)	The port priority parameter helps determine which bridge port becomes the
	designated port. In a network topology that has multiple bridge ports connected to
	a single segment, the port with the lowest port priority becomes the designated
	port for the segment.
Cost	The port path cost parameter is used to help determine the designated port for a
	segment. Generally speaking, the faster the port, the lower the path cost. A
	setting of zero (0) indicates that the cost will be set to the appropriate default after
	the link speed has been auto-negotiated.
State	Shows the current state of the port. The state field can be one of the following:
	Discarding (DISC), Learning (LRN), Forwarding (FWD), or
	Disabled (DSB).
Role	Shows the current role of this port in the Spanning Tree. The port role can be one
	of the following: Designated (DESG), Root (ROOT), Alternate (ALTN), Backup
	(BKUP), Master (MAST), or Unknown (UNK).
Designated Bridge	Shows information about the bridge connected to each port, if applicable.
	Information includes the priority (hex) and MAC address of the Designated Bridge.
Designated Port	The port ID of the port on the Designated Bridge to which this port is connected.
	Information includes the port priority (hex) and the port number (hex).
Hello	The hello time parameter specifies, in seconds, how often the root bridge
	transmits a configuration bridge protocol data unit (BPDU). Any bridge that is not
	the root bridge uses the root bridge hello value.
Type	Type of link connected to the port, and whether the port is an edge port. Link type
	values are AUTO, P2P, or SHARED.

Information Commands 30