Bridging

Filtering Database

When the 9H42x-xx switch is using Transparent Bridging, the Filtering Database, which makes up the IEEE 802.1d Source Address Table, is used to determine which frames will be forwarded or filtered between the 9H42x-xx module’s bridging interfaces.

Transparent bridges like the 9H42x-xx use the Filtering Database to determine a packet’s route through the bridge. During initialization, a bridge copies the contents of its Permanent Database to the Filtering Database. Next, the bridge learns network addresses by entering the source address and port association of each received packet into the Filtering Database. When in the Forwarding state, the bridge examines each received packet and compares the destination address to the contents of the Filtering Database. If the destination address is located on the network from which the packet was received, the bridge filters (does not forward) the packet. If the destination address is located on a different network, the bridge forwards the packet to the appropriate network. If the destination address is not found in the Filtering Database, the bridge forwards the packet to all networks. To keep Filtering Database entries current, older entries are purged after a period of time, which is called the Dynamic Ageing Time.

Entries to the Source Address Table are one of four types: Static, Permanent,

Dynamic, or Learned.

•Static entries are addresses that you add to the Static Database (via the Filtering Database window). These entries are not subject to the ageing timer, and will remain in the Source Address Table until the 9H42x-xx module is shut down.

•Permanent entries are also addresses that you add to the Static Database (via the Filtering Database window); once classified as permanent, these are stored in the device’s battery-backed RAM and are preserved between power-up cycles.

•Dynamic entries are addresses that you add to the Static Database (via the Filtering Database window). These entries are subject to the Ageing Timer, and will be automatically deleted if they do not transmit data during one complete timer cycle. You can set the ageing timer via the Ageing Time field in the Filtering Database window.

•Learned entries are addresses that are added to the Learned Database through the bridge’s learning process. Like Dynamic entries, these entries are subject to the Ageing Timer, and will be automatically deleted if they do not transmit data during one complete timer cycle.

Learned address entries are divided into two types: Learned and Self. Address entries classified as Learned have transmitted frames destined for a device attached to a network segment installed in the 9H42x-xx module; address entries classified as Self are those that have sent a frame with a source address of one of the 9H42x-xx module’s available bridge port interfaces.

Filtering Database

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Cabletron Systems 9H42X-XX manual Filtering Database, Dynamic, or Learned
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9H42X-XX specifications

Cabletron Systems 9H42X-XX is an advanced networking device recognized for its robust performance and reliability in various enterprise environments. Designed to meet the growing demands of data communication, this model serves as a vital component of network infrastructure, offering a myriad of features and technologies.

One of the standout characteristics of the 9H42X-XX is its high-speed data processing capabilities. Equipped with multiple Gigabit Ethernet ports, it ensures rapid data transfer rates, making it ideal for bandwidth-intensive applications. This model supports both IPv4 and IPv6 addressing, ensuring compatibility with modern networking standards and future-proofing the investment for organizations transitioning to newer technologies.

The 9H42X-XX excels in flexibility and scalability, accommodating a range of networking topologies. Its modular design allows for the addition of different interface cards, catering to specific networking requirements such as VoIP, video streaming, and cloud services. This adaptiveness is crucial for organizations that must optimize their network as needs evolve over time.

Security is a primary consideration in the design of the 9H42X-XX. With built-in firewall capabilities and support for advanced encryption protocols, data integrity and confidentiality are ensured. Furthermore, the device offers robust access control features, allowing organizations to define user permissions and protect sensitive information from unauthorized access.

Another important feature is the comprehensive management options available with the 9H42X-XX. It provides a user-friendly interface for network administrators to monitor traffic, configure settings, and troubleshoot issues. This ease of management contributes to reduced downtimes and better overall network efficiency.

Additionally, the Cabletron Systems 9H42X-XX is known for its durability and performance consistency in varying environmental conditions. This resilience makes it suitable for both indoor and outdoor deployments, further extending its usability across different types of organizations.

In summary, the Cabletron Systems 9H42X-XX is a versatile networking solution that combines high-speed connectivity, security features, and ease of management within its robust architecture. Its adaptability and technical specifications position it as a reliable choice for enterprises looking to upgrade their network infrastructure and accommodate future growth.
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