Introduction
The Nokia 1850 TSS-320H is a high-capacity, converged Transport Service Switch (TSS) designed for metro core, regional, and backbone transport networks. As a key member of the Nokia 1850 TSS series, it integrates SDH/SONET, Ethernet, MPLS, and DWDM/ROADM functionalities into a single, carrier-grade platform, supporting seamless migration from TDM to packet-based transport.