Beta Draft Confidential
10-561/19/05 ATM Services Configuration Guide for CBX 3500, CBX 500, GX 550, and B-STDX 9000
Configuring ATM PVCs
Configuring Frame Relay-to-ATM Interworking Circuits
BC (kbits)  Committed burst size (Bc). Enter the maximum amount of data, in kb, 
that the network attempts to transfer under normal conditions during a 
specified time interval (Tc, calculated as Bc/CIR). This value must be 
greater than zero (0) and is typically set to the same value as CIR.
MBS (cell) Displays the maximum burst size (MBS) that is calculated from the Bc 
value you enter.
BE (kbits)  Excess Burst Size. Enter the maximum amount of uncommitted data, in 
Kbits, the network will attempt to deliver during a specified time 
interval, Tc. Tc is calculated Bc/CIR. The network treats this data as 
discard eligible (DE) data. 
Note: For ATM UNI DS3/E3 modules, if the sum of Bc + Be is greater 
than the value of MBS, you will get an error. If you set Bc = CIR and Be 
to 0 (zero), traffic shaping is disabled on the ATM side of the circuit and 
MBS is forced to equal 32.
PCR (cells/sec) Displays the PCR that is calculated from the Be value you enter.
Rate Enf. 
Scheme
Select Simple (default) or Jump. The configurable rate enforcement 
scheme provides more flexibility, increased rate enforcement accuracy, 
and improved switch performance. See “Rate Enforcement Schemes” on 
page 10-46 for more information.
Delta BC (bits) The maximum number of bits the network agrees to transfer over the 
circuit (as committed bits) during the measurement interval provided 
there are positive Bc credits before receiving the frame, but negative Bc 
credits after accepting the frame. Set the number of Delta Bc bits for this 
circuit between zero (0) - 65528 (default 65528). 
Delta BE (bits) The maximum number of bits the network agrees to transfer over the 
circuit (as excess bits) during the measurement interval provided there 
are positive Be credits before receiving the frame, but negative Be 
credits after accepting the frame. Set the number of Delta Be bits for this 
circuit between zero (0) - 65528 (default 65528).
Table 10-12. Add PVC: Traffic Type Tab Fields (Continued)
Field Action/Description