3-1
Chapter 3
Technical Overview
SmartSwitch Architecture
The SmartSwitch Architecture of the 9H531-18 and 9H532-18 modules, 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 modules make
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 modules 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
.