The optical ports use SFP optical modules and support hot swapping. Intended Audience OptiX OSN 3500 System Description is intended for any one who needs a general command of the features, applications, structure and technical specifications of the OptiX OSN 3500. Page 9 About This Manual OptiX OSN 3500 TM - SD Conventions The following conventions are used. The Huawei OptiX OSN 3500 is a new-generation optical transmission system developed by Huawei. It adopts a unified switching architecture and can function as an MPLS/MPLS-TP-based packet device or a TDM device. The OSN 3500 supports flexible networking topologies including mesh, ring, and intersecting ring.