Configuring Transparent Bridging

Transparent and SRT Bridging Configuration Task List

The primary application of transparently bridged VLANs constructed in this way is to separate traffic between bridge groups of local network interfaces, to multiplex bridged traffic from several bridge groups on a shared interface (LAN or HDLC serial), and to form VLANs composed of collections of bridge groups on several routers. These VLANs improve performance because they reduce the propagation of locally bridged traffic, and they improve security benefits because they completely separate traffic.

In Figure 9, different bridge groups on different routers are configured into three VLANs that span the bridged network. Each bridge group consists of conventionally bridged local interfaces and a subinterface on the backbone FDDI LAN. Bridged traffic on the subinterface is encapsulated and “colored” with a VLAN identifier known as a security association identifier common to all bridge groups participating in the VLAN. In addition, bridges only accept packets bearing security association identifiers for which they have a configured subinterface. Thus, a bridge group is configured to participate in a VLAN if it contains a subinterface configured with the VLAN’s characteristic security association identifier. See the “Complex Integrated Routing and Bridging Example” section on page 66 for an example configuration of the topology shown in Figure 9.

Note The 802.10 encapsulation used to “color” transparently bridged packets on subinterfaces might increase the size of a packet so that it exceeds the MTU size of the LAN from which the packet originated. To avoid MTU violations on the shared network, the originating LANs must either have a smaller native MTU than the shared network (as is the case from Ethernet to FDDI), or the MTU on all packet sources on the originating LAN must be configured to be at least 16 bytes less than the MTU of the shared network.

Figure 9 Transparently Bridged VLANs on an FDDI Backbone

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Cisco IOS Bridging and IBM Networking Configuration Guide

BC-31

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Cisco Systems BC-23 manual BC-31, Transparently Bridged VLANs on an Fddi Backbone

BC-23 specifications

Cisco Systems has long been a leader in the networking industry, and its BC-23 model exemplifies the company's commitment to innovation and performance. Aimed at enhancing business operations, the BC-23 is tailored for organizations looking for robust solutions that support their digital transformation efforts.

One of the standout features of the Cisco BC-23 is its advanced networking capabilities. It supports high-speed data transmission, enabling seamless communication across networks. With multi-gigabit Ethernet ports, the BC-23 facilitates faster data rates, accommodating the increasing bandwidth demands of modern applications. This feature is particularly beneficial for businesses that rely heavily on cloud services, video conferencing, and data-heavy applications.

Security is a top priority, and the Cisco BC-23 incorporates cutting-edge security measures. Integrated threat detection and prevention systems help safeguard sensitive data from cyber threats. Additionally, the device supports secure access protocols, ensuring that only authorized users can connect to the network. This multi-layered security approach not only protects the network infrastructure but also secures the integrity of the data being transmitted.

Another significant characteristic of the BC-23 is its support for software-defined networking (SDN). This technology allows businesses to manage their networks through centralized software applications, facilitating real-time adjustments and optimizations. The flexibility afforded by SDN is especially advantageous in dynamic environments where network demands can shift rapidly.

The Cisco BC-23 also offers enhanced management features, allowing IT teams to monitor network performance and analytics effectively. This visibility into network operations enables organizations to identify potential issues before they escalate, minimizing downtime and keeping business processes smooth.

Furthermore, the BC-23 is designed for scalability. As organizations grow, their networking needs evolve, and the BC-23 can easily adapt to these changes. Businesses can add additional devices and capabilities without the need for a complete overhaul of their existing infrastructure.

With its combination of speed, security, and scalability, the Cisco Systems BC-23 is an invaluable asset for modern businesses. It stands out not just as a networking device but as a comprehensive solution that meets the demands of today's fast-paced, technology-driven environment. As companies continue to leverage digital tools for growth and efficiency, the BC-23 will undoubtedly play a significant role in their success.