RuggedCom RS400 manual Bridge Priority, Hello Time, Max Age Time, Transmit Count, Forward Delay

Spanning Tree

Default: On

Enable/disable RuggedCom proprietary eRSTP (enhanced RSTP) enhancements

Bridge Priority

Synopsis: { 0, 4096, 8192, 12288, 16384, 20480, 24576, 28672, 32768, 36864, 40960, 45056, 4 9152, 53248, 57344, 61440 }

Default: 32768

Bridge Priority provides a way to control the topology of the STP connected network. The desired Root and Designated bridges can be configured for a particular topology. The bridge with the lowest priority will become root. In the event of a failure of the root bridge, the bridge with the next lowest priority will then become root. Designated bridges that (for redundancy purposes) service a common LAN also use priority to determine which bridge is active. In this way, careful selection of Bridge Priorities can establish the path of traffic flows in normal and abnormal conditions.

Hello Time

Synopsis: 1 to 10

Default: 2 s

Time between configuration messages issued by the root bridge. Shorter hello times result in faster detection of topology changes at the expense of moderate increases in STP traffic.

Max Age Time

Synopsis: 6 to 40

Default: 20 s

The time for which a configuration message remains valid after being issued by the root bridge. Configure this parameter with care when many tiers of bridges exist, or when slow speed links (such as those used in WANs) are part of the network

Transmit Count

Synopsis: 3 to 100

Default: 32

Maximum number of configuration messages on each port that may be sent in a special event (such as recovering from a failure or bringing up a new link). After the maximum number of messages is reached, RSTP will be limited to 1 message per second. Larger values allow the network to recover from failed links more quickly. If RSTP is being used in a ring architecture the transmit count should be larger than the number of switches in the ring.

Forward Delay

Synopsis: 4 to 30

Default: 15 s

The amount of time a bridge spends learning MAC addresses on a rising port before beginning to forward traffic. Lower values allow the port to reach the forwarding state more quickly, but at the expense of flooding unlearned addresses to all ports.

Max Hops

Synopsis: 6 to 40

Default: 20

This parameter is only relevant for MSTP - ignore it otherwise.

This parameter specifies the maximum possible bridge diameter inside an MST region. MSTP BPDUs propagating inside an MST region carry a time-to-live parameter that is decremented by

ROS™ v3.5 148 RS400