Description Designed to handle the growth and increasing complexity of digital networks, the 3500 Series Data Service Unit (DSU) combines a wide array of features into a single, economical and highly functional unit. The 3500 Series DSU enables the user to make maximum use of digital data services. Based on a field-proven Bell Laboratories digital data pump, the 3500 Series DSU provides a cost-effective solution for a broad range of operating environments. Because the 3500 Series DSU can operate as a Limited Distance Modem (LDM) in a point-to-point application, it is particularly ideal for campus environments that require a single unit to operate over a wide range of speeds. The 3500 Series DSU is available in both standalone and high-density carrier card models. The compact 3510 Standalone unit is designed especially for use at tributary sites, while the 3511 Carrier Card mounts in the high-density COMSPHERE 3000 Series Carrier and is ideal for central site applications.
