STM1-2M CR MMF W/CPU-2 The STM1-2M MMF Card with CPU-2 is a local ATM (LATM) STM1 interface card operating at the SDH STM1 rate of 155 Mbps, with 32k cell buffering per card. The multi-mode fiber (MMF) optional interface has a typical range of 2km. The STM1-2M MMF Card is a single port card and is compliant to the requirements of the ATM Forum UNI Specification (Version 3.1) and the ATM Forum B-ICI Specification (Version 2.0). This card is designed to accept the optional Multi-Service Traffic Module (MSTM, 90-4724-01) or enhanced Traffic Shaping Module (eTM, 90-7695-01) which, when installed, provides enchanced traffic management features. This card variant is shipped with R4.3 S/W.