The Cisco Packet-over-T3/E3 Service Module for the Cisco Integrated Services Routers offers the first software-configurable T3/E3 product from Cisco. This flexible T3/E3 module allows you to switch between T3 and E3 applications with a single Cisco IOS® Software command. This feature offers you increased flexibility and investment protection by allowing a Cisco partner, service provider, or enterprise customer to stock only a single product that can be deployed internationally. The increased demand for bandwidth over the WAN and more attractive pricing of T3/E3 links by service providers has led to steady growth in T3/E3 deployments around the world. The T3/E3 module eliminates the need for an external data service unit (DSU), reduces provisioning costs, and provides highly manageable T3/E3 line termination. The module provides an integrated line interface unit (LIU) DSU that allows T3 or E3 lines to be directly terminated on a Cisco router, eliminating the need for external DSU equipment, simplifying the T3/E3 line management, reducing provisioning cost, and freeing valuable rack space. The T3/E3 module supports the proprietary subrate and scrambling features of T3 DSU vendors such as Digital Link, Larscom, and ADC Kentrox. Subrate support in the module maximizes the utility of these products in service provider environments. By simultaneously supporting interoperability with a wide range of third-party DSU vendors, this module offers the flexibility to support installed equipment without locking customers into a proprietary solution. The Cisco T3/E3 Service Module provides direct connectivity to a T3 line for full-duplex communications at the T3 rate of 44.736 MHz and full-duplex E3 communications at 34.368 MHz. Each T3 or E3 port consists of a pair of 75‑ohm BNC coaxial connectors (Type RG-59), one for transmit data and one for receive data, along with six LED indicators for line status. The T3/E3 module is supported in all Cisco IOS Software feature sets, and there are no additional memory requirements. Key Benefits The combination of T3 and E3 options in a single module provides the following important customer benefits: - Physical space savings: Eliminates the need for external DSU device, saving valuable rack space - Simplified management: Eliminates the need for two separate monitoring tools - Software-configurable T3/E3: Provides the flexibility to deploy a single module worldwide