Bridge Parameters

In this interface, you can modify and query bridge parameters.

Navigation Path

For RTN NEs, in the NE Explorer, select the NE and choose Configuration > Ethernet Protocol Configuration > MSTP Configuration from the Function Tree. Then, click the Bridge Parameters tab.

Parameters

**Table 1** Descriptions of the parameters for Bridge Parameters
Field	Value	Description
Port Group ID	Example: 2	Display the ID of the port group. Only the ID that is automatically allocated can be used.
MST Domain Name	Character string Default: MAC address of the bridge	Display and set the MST domain name. Modification of the MST domain name causes change of the network topology. Two switches belong to the same MST domain only when the MST domains configured on the two switches have the same name, when all VLAN mapping tables corresponding to the spanning tree instances in the MST domains are the same, and when redaction levels of the MST domains are the same and the two MST domains are directly connected.
Redaction Level	0-65535 Default: 0	Display and set the redaction level. Modification of the redaction level causes change of the network topology.
Mapping List	1-300	Set the mapping list. Modification of the mapping list causes change of the network topology.
MIST ID	0-16	Display the MIST ID. The number 0 indicates CIST.
VLAN ID	1-4094	Display and set the VLAN ID. The numbers 0 and 4095 are always mapped to CIST.
MST Domain Max Hop Count	1-40 Default: 20	Display and set the maximum count of hops in an MST domain. The scope of an MST domain depends on the maximum count.
Network Diameter	2-7 Default: 7	Display and set the network diameter. The network diameter is the length of the trail with the most switches in the network. The count of switches on the trail indicates the network diameter. The network diameter is one parameter of the network scope, which increases with the network diameter. The network diameter is valid only for CIST but for MIST. When the user configures the network diameter of a switch, the MSTP performs calculation and sets Hello Time, Forward Delay and Max Age to reasonable values.
Hello Time (s)	Example: 2	Set the hello time. A switch uses this parameter to check whether the link is faulty. The switch sends hello packets to surrounding switches every hello time to check whether there are link faults. NOTE: The parameters of the bridge time are recommended to be optimized through the configuration of the network diameter, instead of the configuration of the Forward Delay, Hello Time, and Max Age bridge time parameters. When the bridge time parameters are configured, the value of the diameter of the switching network is invalid. For the Forward Delay, Hello Time, and Max Age bridge, the following constraints should be met: 2(hellotime+1) ≤ maxage ≤ 2(forwarddelay-1).
Max Age (s)	Example: 20	Set the maximum age. This parameter is used to judge whether the configuration message expires. The switch will discard the expired configuration message.
Forward Delay (s)	Example: 15	Set the forward delay. The forward delay time is used during the bridge state transition. The link fault results in the recalculation of the spanning tree and then the structure of the spanning tree is changed. The new configuration message cannot be transmitted over the entire network immediately. If the new root port and designated port forward the data immediately, a temporary loop may occur. Thus, a state transition mechanism is adopted. That is, the root port and the designated port must stay in a transition state before they can forward data. The transition state turns into the forwarding state upon Forward Delay. This delay guarantees that the new configuration message has spread throughout the entire network.
Port	Example: Slot-Board Name-Port (Port No.)	Display the port.
Enable Edge Attribute	Disabled, Enabled Default: Disabled	Display and set the edge attribute. The edge port indicates the port that is neither directly connected to any switch nor indirectly connected to any switch through the network in connection to the port. If the user specifies a port as the edge port when the port transfers from the congestion status to the forwarding status, the edge port can quickly migrate without the wait of the delay. The user can specify the port connected to the terminal as the edge port.
Actual Edge Attribute	Disabled	Display the actual edge attribute.
Point-to-Point Attribute	auto, false, true Default: auto	Display and set the point-to-point attribute. auto: point-to-point link attributes or non-point-to-point link attributes, as detected false: non-point-to-point link attributes true: point-to-point link attributes The point-to-point link is the direct link between two switches. If a port is connected to a point-to-point link or any other link, the connection of the port is set accordingly on all spanning tree instances. If the physical link connected to a port is not a point-to-point link, incorrect configuration of the link as a point-to-point link may introduce temporary path loop.
Actual Point-to-Point Attribute	false, true	true: point-to-point link false: non-point-to-point (Shared Link)
Max Transmit Packet Count	1-255 Default: 3	Display and set the maximum count of transmitted packets. This parameter indicates the maximum number of MSTP packets that can be transmitted within a hello-time period. In the case of an Ethernet port, the maximum number depends on the physical state of the port and the network structure. Set this parameter according to the network. If this parameter is set to an excessively large value, a great number of MSTP packets are transmitted within each hello-time period. As a result, these packets occupy many network resources.