The Agilent OTDR Modules N391x work together with the Agilent Modular Network Tester, and are easy to snap on. The OTDR application is uploaded in seconds due to the dynamic software architecture, and allows plug and play operation. Each OTDR test engine has built-in RISC processing power for fast and accurate trace acquisition and data processing. These test engines work in parallel processing mode with other connected test engines, for example, the 1x12 Switch module. All OTDR modules can be shared between multiple users, without the need for any software changes.