Cabletron Systems NB30 manual Protocol, Hello Time, Max Age, Forwarding Delay, Hold Time

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NB-30 Bridging

Protocol

Displays the Spanning Tree Algorithm Protocol type the NB-30 is currently using. The choices are:

¥802.1

¥DEC (DEC Lanbridge 100)

¥None

The following four Þelds display values used for various Spanning Tree timers that are set at the Root Bridge and this bridge. In Spanning Tree operations, the value used for the tree is the one set at the Root Bridge (with the exception of Hold Time, which is a Þxed value); but you can change the value for each bridge on your network in the event that it becomes Root.

Hello Time

This parameter indicates, in seconds, the length of time the Root Bridge (or bridge attempting to become the Root) waits before resending ConÞguration BPDUs. The range for this Þeld is 1 to 10 seconds, with a default value of 2 seconds. The Root Bridge sets the Hello Time.

Max Age

This parameter displays the bridgeÕs BPDU ageing timer. This controls the maximum time a BPDU can be retained by the bridge before it is discarded. During normal operation, each bridge in the network receives a new ConÞguration BPDU before the timer expires. If the timer expires before a ConÞguration BPDU is received, it indicates that the former Root is no longer active. The remaining bridges begin Spanning Tree operation to select a new Root. The current Root Bridge on the network sets the Max Age time. The range for this Þeld is 6 to 40 seconds, with a default value of 20 seconds.

Forwarding Delay

This parameter displays the time period which elapses between states while the bridge is moving to the Forwarding state. For example, while moving from a Blocking to a Forwarding state, the port Þrst moves from Blocking to Listening to BPDU activity on the network, remains there for the Forward Delay period, then moves to the Learning State (and remains in it for the Forward Delay period), and Þnally moves into a Forwarding state. This timer is set by the Root Bridge. During a topology change, the Forward Delay is also used as the Filtering Database Ageing Time (refer to the next section), which ensures that the Filtering Database maintains current topology information.

Hold Time

This parameter displays the minimum time (1 second) that can elapse between the transmission of ConÞguration BPDUs through a bridge port. The Hold Time ensures that ConÞguration BPDUs are not transmitted too frequently through any bridge port. Receiving a BPDU starts the Hold Timer. After the Hold Timer expires, the port transmits its ConÞguration BPDU to send conÞguration information to the Root. The Hold Time is a Þxed value, as speciÞed by the IEEE 802.1d speciÞcation.

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Bridge Spanning Tree

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Contents NB30 User’s Guide Page Virus Disclaimer Page Restricted Rights Notice Page Contents Contents IndexUsing the NB-30 Bridge User’s Guide IntroductionRelated Manuals IntroductionUsing the Mouse Software ConventionsCommon NB-30 Bridge Window Fields Device DescriptionUsing Window Buttons Accessing On-line Documentation Using On-line HelpGetting Help NB-30 Bridge Firmware Getting Help from the Cabletron Systems Global Call CenterIntroduction NB-30 Bridge Firmware NB-30 Bridge Chassis View Viewing Chassis Information Front Panel Information Menu Structure DateHelp Menu Device MenuUtilities Menu Board MenuNB-30 Bridge Port Status Display Chassis ManagerManaging the Bridge Viewing Hardware TypesSetting the Device Date and Time Edit Date WindowEnabling and Disabling Bridging NB-30 Bridge Chassis View Managing the Bridge NB-30 Bridging Bridging BasicsAbout Transparent Bridging Viewing and Managing Bridging InterfacesBridge Status Bridge Status Condition Bridge LocationBridge State on Interface OK/SQE onBridge Status on Remote Port Interface Bridge Port Address Local Ethernet Port Interface NameInterface Type Segment NameAccessing Bridge Status Window Options Enabling and Disabling BridgingBridge Statistics Performance GraphsFrames Received Frames ForwardedFrames Filtered Discarded Inbound Ethernet Port Only Device ErrorsNothing Forwarded OutboundTotal Errors CRC ErrorsTimeout Remote Port Only Out of Window Coll. Ethernet Port OnlyBridge Summary Statistics Bridge Summary Statistics WindowEthernet and Remote Port Statistics Remote Port Statistics Window Xmit Aborts Ethernet Port Only Packets Filtered Blue Ethernet Port OnlyOOW Ethernet Port Only Framing TimeoutBridge Spanning Tree GiantsBridge Spanning Tree Window Bridge Level Parameters Hello Time Forwarding DelayProtocol Max AgeBridge Port Level Parameters Changing Bridge Priority Configuring Spanning TreeTopology Changing the Spanning Tree Algorithm Protocol TypeChanging Hello Time Changing Forwarding Delay TimeChanging Max Age Time Changing Port Priority Filtering DatabaseChanging Path Cost NB-30 Bridging Capacity TypeNumber Ageing TimeAddress Configuring the Filtering DatabaseList Port FilteringChanging the Port Filtering Action Changing the Type of EntryAdding or Deleting Individual Filtering Database Entries DSX-1 Summary Erasing Entries from the Permanent or Acquired DatabasesConfiguring, Running, and Checking the Loopback Test Bridge DSX-1 Summary WindowRestoring Bridge Defaults Viewing the T1 Link Channel StatusSelect Reset Counters Resetting Bridge CountersSelect Restore Defaults Restarting the BridgeNB-30 Bridging Restarting the Bridge NB-30 Bridging Restarting the Bridge Index Index-2 Index-3 Index Index-4

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.
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