One of the main features of the Small Enterprise Design Profile is that it provides a loop-free topology, minimizing re-convergence times and eliminating the complexities of certain technologies, such as spanning tree. The architecture supports different designs for the access layer, including the traditional multi-tier access layer design and the more optimal routed access design. The Small Enterprise Design Profile ensures a loop-free topology for both access designs, however the routed access approach provides for up-link load balancing and virtually eliminates any issues associated with spanning tree.
Another important feature of the Small Enterprise Design Profile is that it uses a collapsed network design where the core and distribution layers at each site are collapsed into one layer, allowing the use of a single device (reducing network cost) while maintaining most of the benefits of the traditional three-tier hierarchical model (core, distribution, and access).
The Small Enterprise Design Profile accommodates different levels of redundancy. This includes the use of redundant supervisor engines with Stateful Switchover (SSO) and Non-Stop Forwarding (NSF) capabilities on Cisco Catalyst 4500 switches, Cisco's Virtual Switching Systems (VSS) technology on the Cisco Catalyst 6500 series, and stackwise technology on the Cisco Catalyst 3700 series switches. The last two features allow two or more distribution switches to be combined into a single virtual switch from a management and data forwarding perspective. Redundancy at the link levels is implemented by using EtherChannel technology, where multiple physical links are bundled into a single EtherChannel. EtherChannel significantly simplifies the network response to an individual link failure. If an individual link in EtherChannel fails, the interface does not trigger any network topology changes, thus minimizing impact to network and application performance and improving network convergence