Cabletron Systems NB30 Bridge Spanning Tree, Framing, Giants, Inbound Ethernet Port Only, Timeout

Models: NB30

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NB-30 Bridging

CRC

The total number of frames received by the port that had Cyclical Redundancy Check (CRC) errors.

Framing

The number of frames received by the port from the network that were misaligned Ñ that is, in which a byte of data in the packet contained less than 8 bits.

Giants

The number of frames that were received by the port which were too large for the network. A giant exceeds the maximum Ethernet frame size of 1518 bytes (excluding preamble).

Ethernet and Remote Port Packet Discarded Statistics

These Þelds display the number of packets that were discarded at one of the bridge ports. Note that the Inbound count applies to the Ethernet port only.

Inbound (Ethernet Port Only)

Displays the number of packets received by the port which were discarded for any reason (lack of buffer space, the frame time-to-live was exceeded, or the packet was too large for the network).

LOB

The number of frames that were discarded at the port speciÞcally because the NB-30Õs frame buffer was unable to keep up with the rate of trafÞc on the network.

Timeout

The number of frames that were discarded at the port because the frameÕs time-to-live (the maximum time for forwarding) was exceeded before it could be transmitted by the port.

Bridge Spanning Tree

The Bridge Spanning Tree window allows you to display and modify the NB-30Õs bridge port information and protocol parameters relating to the Spanning Tree Algorithm.

In a network design with multiple transparent bridges placed in parallel (i.e., attached to the same local network segment), only a single bridge should forward data through the LAN, leaving the remaining bridges on the segment in a standby state so that another can assume the bridging responsibility (should the currently active bridge go down). The Spanning Tree Algorithm (STA) is the method that bridges use to communicate with each other to ensure that only a single data route exists between any two end stations.

Bridge Spanning Tree

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Cabletron Systems NB30 manual Bridge Spanning Tree, Framing, Giants, Inbound Ethernet Port Only, Timeout