...
Type | Description |
|---|---|
Use-Based | These are charges for services that are incurred when they are used, like the use of Fab processing equipment. For example, if a user uses a piece of equipment in the Fab, they will be charged for that specific activity, based on the time spent using that equipment and/or the materials used for the activity. |
Fixed-Rate | These are charges for services that cost a specific amount for each billing period (each month). For example, a user may be charged $10 each month for an access card. |
Because of the different nature of these charges, you will see differences when working with allocations for these charges:
- Splitting of Charges: When you specify more than one cost object for payment of fixed-rate charges, you must provide percentages for each of those cost objects, so that the total adds up to 100% and charges are fully covered. However, for use-based charges, you do not provide percentages. Instead, the user in is presented with a list of cost objects (accounts) from which to choose when engaging a machine in Coral. It is up to the user to select the correct cost object.
- Allocation Dates: Since fixed-rate charges are applied to the entire month, allocations for these charges must extend from the beginning of a billing period (the first day of the month) to the end of a billing period (the last day of the month). So, for example, charges for compute services for user Jane Doe could be allocated to cost object 1234567 from June 1 - September 30, but not June 3 - September 6. This restriction does not apply to use based charges.
- Retroactive Changes: Since fixed rate charges are billed at the end of the month, changes to allocations for those charges can be made any time up to the end of the month and will be reflected in that months billing. However, for use based charges, those charges are assigned to a cost object at the time they are incurred, so allocations can only be changed for the current day forward.*
*If you really want the details: when you modify cost object allocations, you can add and remove multiple allocations at once. So if you had allocations for Fab processing to cost objects A and B and you removed both of those and added cost objects C and D, MUMMS would not know what to do with the existing activities that had been charged to cost objects A and B (whether they should be applied to cost object C or D or some combination of the two). There is, however, a separate function in MUMMS that will allow a one-to-one replacement of a cost object retroactive to the beginning of the current billing period see the Replacing a Cost Object page for details.