NB-30 Bridging

Bridge Level Parameters

Bridge Priority

This Þeld displays the ÒpriorityÓ component of the NB-30Õs unique bridge identiÞer. The Spanning Tree Algorithm assigns each bridge a unique identiÞer, which is derived from the bridgeÕs MAC address and the Priority. The bridge with the lowest value of bridge identiÞer is selected as the Root. A lower priority number indicates a higher priority; a higher priority enhances a bridgeÕs chance of being selected as the Root.

You can edit this text box to change network topology, if needed. The default value is 8000.

Part of a bridgeÕs IdentiÞer is based on its MAC address. In most network installations,

TIP the difference between bridge performance may be negligible. You may, however, Þnd your data bottle-necked in installations where both a low-performance bridge and a high-performance bridge are attached to the same LAN segment, and the two (or more) bridges have the same Priority component set (e.g., at the default 8000 Hex). In such a scenario you may want to alter the Priority component of the higher performance bridge to ensure that it becomes root for the segment (or overall root). Remember, if Priority components are equal, the bridge on the segment with the lowest Hex value of MAC address would have a better chance of being selected as the root bridge Ñ as it would have a lower Bridge IdentiÞer. If your bridges come from multiple vendors, they will have different MAC address values (e.g., Cabletron devices have a lower MAC address than 3Com devices); if they come from the same vendor, the bridge with the earlier manufacture date will be likely to have the lower MAC address value.

Root Priority

The ÒpriorityÓ component of the unique bridge identiÞer for the bridge that is currently the root bridge on the network.

Root Bridge

Displays the MAC address of the bridge that is currently functioning as the Root Bridge.

Root Cost

Indicates the cost of the data path from this bridge to the Root Bridge. Each port on each bridge adds a ÒcostÓ to a particular path that a frame must travel. For example, if each port in a particular path has a Path Cost of 1, the Root Cost would be a count of the number of bridges along the path. (You can edit the Path Cost of bridge ports as described later.) The Root BridgeÕs Root Cost is 0.

Root Port

This Þeld displays the identiÞer (the physical index number) of the NB-30 bridge port that has the lowest cost path to the Root Bridge on the network. If the NB-30 is currently the Root Bridge, this Þeld will read 0.

Bridge Spanning Tree

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Cabletron Systems NB30 manual Bridge Level Parameters

NB30 specifications

Cabletron Systems NB30 is a noteworthy networking device that emerged in the mid-1990s as a critical component for businesses looking to enhance their local area network (LAN) capabilities. Designed primarily for the burgeoning demand of network speed and reliability, the NB30 served as a bridge in networking technology, offering organizations a robust solution to keep up with the advancing digital landscape.

One of the main features of the Cabletron NB30 is its ability to support both Ethernet and Token Ring protocols. This dual compatibility made it an attractive choice for enterprises that were transitioning from older networking systems to newer infrastructures. By accommodating both technologies, the NB30 enabled smoother migrations without necessitating a complete overhaul of existing networking components.

Another significant characteristic of the NB30 is its modular architecture. This design allowed organizations to customize their networking setup according to specific needs and preferences. Users could add or replace modules to enhance functionality, from extra ports to support additional devices or advanced features like network management tools, ensuring that their systems could grow and evolve in tandem with their business requirements.

The NB30 also utilized a stackable design, which facilitated scalability. Organizations could easily connect multiple NB30 units to increase their network capacity and performance. This stacking capability was a significant advantage as it allowed for efficient use of space and resources while providing a path for future growth.

In terms of performance, the Cabletron NB30 boasted a switching capacity that enabled quick data transfer rates, reducing latency and improving overall network responsiveness. This speed was crucial during a period when businesses were increasingly reliant on real-time data exchange and communication.

Additionally, the NB30 incorporated advanced network management features, enabling administrators to monitor traffic, diagnose issues, and implement changes with ease. This level of control was essential for maintaining network health, ensuring that businesses remained operational without unnecessary downtimes.

Overall, Cabletron Systems NB30 played a pivotal role in the evolution of networking technology. Its combination of protocol flexibility, modular design, scalability, and robust performance made it a popular choice for businesses looking to create efficient, dependable networks in an era of rapid technological advancement. The NB30's legacy continues to influence modern networking solutions, demonstrating the importance of adaptability and performance in the ever-changing digital world.