If I have a scenario where the current DSP's are less than the "required DSP's (per Cisco DSP calculator) will I encounter erros during dsp configuration? More specific, I have a 2851 with one Vwic-1mft1-t1 and one Vwic-2mft-t1 plus an FXO-2 vic. I have one PVDM2-16 and one PVDM2-64 on board. I need to configure to allow vics for maximum calls (24, 48 and 2) although they are likely never use all calls at one time (probably no more than 75% of maximum calls at any one time). What I would like to do is also support 4 transcoder sessions and 2 hardware conference bridges on these same DSP's (given that I believe concurrent calls will never go over 75% of max calls and thus some DSP resources available). If no additional DSP's were added, can I configure DSP's for the 4 transcode and 2 conference sessions. Or will I encounter errors during the DSP farm configuration (stating something to the fact that not enough DSP resources available for configuration)?
I think you see the writing on the wall here :) The DSP's used for the Voice terminations (T1's and FXO - reserved in a 1 to 1 ratio) are not dynamic in the sense that you desire. You are going to hit the errors you suggested in your post.
You allocate DSP resources either to voice termination of the voice trunk group or to the DSP farm. Occasionally these allocations can conflict.
If you previously allocated DSP resources to voice termination and you now try to configure a DSP farm, you might find that insufficient DSP resources are available. Conversely, if you previously allocated DSP resources to a DSP farm and you now try to configure a trunk group, you might find that insufficient DSP resources are available.
If your requested configuration is rejected, you have two options:
Insert more DSPs on the voice network module (NM-HDV or NM-HDV2)
Allocate a different voice network module for either the DSP farm or the trunk group
Hope this helps!