The SX/13a is part of the Spirent SX Data Link Simulators product line, which simulates terrestrial and satellite data links for testing internetworking equipment and applications under repeatable and controllable conditions. Utilizing dual-channel, full-duplex operation, these simulators provide bi-directional testing with programmable delays, random bit errors and burst errors. Multiple delay and error events can be programmed into complex sequences to simulate a wide variety of chronic and periodic conditions or events, such as peak traffic and equipment overloads. Three products are included in the SX product line and differ primarily in the speeds supported and extended functionality options available: » SX/12 — Supports speeds up to 8.448 Mbps and remote operation options • SX/13a —- Supports speeds up to 51.84 Mbps and can be upgraded with error targeting and remote operation options « SX/14 — Supports speeds up to 1.55.52 Mbps and can be upgraded with an error targeting interface and remote operation option The SX products consist of a rack-mountable, portable mainframe coupled with at least one interchangeable interface. The interfaces enable the mainframe to connect to different types of data links. Other options extend the SX/1.3a’s functionality. The unit can be used in lab conditions or for live field testing. The primary method of operation is through the front panel keys and LCD screen. Optional modules enable it to be operated remotely via a PC or other type of terminal. This allows the test set to be placed permanently in a network, if necessary. Typical simulator applications include testing the operation, performance and reliability of multiplexers, bridges, encrypters. network applications and other communications hardware and software. When used for link simulation, these simulators physically connect directly between two pieces of equipment to replace conventional data links, such as satellite connections, WANs or telephone networks. They can also be used in line with an actual data link to add additional delays or errors, or to simulate the effects of adding an additional link to the system.