Chapter 3
Technical Overview
SmartSwitch Architecture
The SmartSwitch Architecture of the 9E531-24 module, as shown in Figure 3-1,is configurable for one of two modes of operation: traditional IEEE 802.1 switching, or SecureFast switching. The module supports only one of these modes of operation at any one time.
When operating in traditional IEEE 802.1 switch mode, the 9E531-24 makes filtering/forwarding decisions based on Destination Address (DA), with standard IEEE 802.1D learning. 802.1Q VLANs are also supported.
Spanning tree operation for the 9E531-24 is configurable to adhere to IEEE 802.1D, DEC, or none. The default Spanning Tree Algorithm is 802.1D.
When operating in SecureFast switch mode, all filtering/forwarding decisions are made on a DA-SA pair and its in and out port on a connection-orientated basis. SecureFast switching mode provides value-added network services including dynamic VLANs, Topology, Connectivity, IP Multicast, Control, Security, Application, Address Management, Dynamic Mapping, and Directory services. For example, Topology Services includes configurable options ranging from simple spanning tree implementations to fully-meshed active topologies. Other services and features supported in SecureFast switching mode are described in detail in the Cabletron White Paper, IP Host Communication in Bridged, Routed and SecureFast Networks.
