STM1-2M IR W/CPU-2 The STM1-2M IR UNI/NNI Card with CPU-2 is both a UNI and NNI STM1 ATM interface card operating at the SONET STM1 rate of 155 Mbps, with 32k cell buffering per card. The Intermediate Reach (IR) single mode fiber optical interface has a total loss budget of 12 db. The STM1-2M IR is a single port card 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 Shaping Module (MSTM, 90-4724-01) or enhanced Traffic Shaping Module (eTM, 90-7695-01) which, when installed, provides enhanced traffic management features. This card variant is shipped with R5.0 S/W. This card is also supported on R2.0 of the 7670 ESE. Note that only the eTM is supported for traffic shaping on the ESE.