Viewing Performance and ATM Statistics 203Total CRC Errors — The number of cells received with uncorrectable sequencenumber CRC error.Total OAM Cells Received — The number of OAM (Operations, Administration,and Maintenance) cells received over the virtual circuit; these cells carry OAMinformation used for network management.Total OAM Cells Transmitted — The number of Operations Administration andMaintenance (OAM) cells transmitted over the virtual circuit.Current Cell Status — The cell loss status: no loss (1) or loss (2). The Current CellStatus is set to loss when cells are lost for the number of milliseconds specified bythe Cell Loss Integration Period defined for the CBR virtual circuit. You define theCLIP when you create the VC.Data Bytes To (structured data ports only) — The data bytes to the cell bus. Usethis value to set the DBA Bits Mask CBR port parameter. In most cases, the defaultDBA Bits Mask (127) is appropriate. If you are experiencing problems with a CCScircuit, however, you can set the DBA Bits Mask to monitor different bits. Checkthe Data Bytes To value, and set the DBA Bits Mask to that value.When you check the data bytes, you must first make sure that the circuit is in anidle state (phone onhook). If you cannot access the equipment to see whether ornot the circuit is in idle, then check the data bytes for at least 30 seconds (aboutseven updates). If the Data Bytes To value remains the same for 30 seconds ormore, it is safe to assume that the circuit is in an idle state.Viewing VoiceCompression ModuleStatisticsYou can view performance monitoring, virtual circuit, and port activity statistics forthe Voice Compression module.To view VCM statistics:1 From the Card Statistics menu, shown earlier in Figure 161, enter the numbercorresponding to the slot in which the VCM for which you want to view statisticsis installed (7 or 8) to open the VCM Card Statistics menu, shown in Figure 164.Figure 164 VCM Card Statistics Menu
