TapeTrack Documentation

====== Billing Terminology  ======

===== Storage Billing Modes =====

Storage Billing Modes determine how the billable storage quantity is calculated during a billing period.

Storage charges can be based on either:

  * The number of actual Volumes stored.
  * The number of storage slots used or allocated.

The selected mode determines whether billing uses accumulated daily quantities, the highest recorded quantity, or the lowest recorded quantity.

===== Storage Modes =====

^ Mode ^ Meaning for Billing ^
| **Storage** | The general billing category for Volumes held in a Repository during the billing period. The selected Storage Billing Mode determines how the billable quantity is calculated. |
| **Daily Total** | The sum of the actual inventory count recorded for each day. The resulting quantity is measured in Volume-days and is normally used for per-Volume, per-day billing. |
| **Real High-Water** | The highest number of actual Volumes stored at any point during the billing period. |
| **Real Low-Water** | The lowest number of actual Volumes stored at any point during the billing period. |
| **Slot Total** | The sum of the daily storage-slot counts. The resulting quantity is measured in slot-days and is used when the Customer is charged for storage capacity. |
| **Slot High-Water** | The highest number of storage slots used or allocated at any point during the billing period. |
| **Slot Low-Water** | The lowest number of storage slots used or allocated at any point during the billing period. |

===== Real and Slot Measurements =====

Real and Slot measurements use different methods to determine the billable storage quantity.

^ Measurement Type ^ Counts ^ Typical Use ^
| **Real** | Actual tape Volumes present in the Repository. | Billing the Customer for each physical Volume stored. |
| **Slot** | Storage positions occupied, allocated or required for the Customer's inventory. | Billing the Customer for storage capacity rather than individual Volumes. |

A Slot quantity may be different from the actual Volume inventory when:

  * Some slots are empty but remain allocated to the Customer.
  * Storage is sold in fixed blocks of slots.
  * Inventory quantities are rounded up to the next storage-unit size.
  * A container or storage position represents more than one Volume.
  * The Customer reserves more capacity than is currently being used.

===== Daily Total Example =====

The following example shows the actual number of Volumes stored over five days.

^ Day ^ Actual Volumes ^
| 1 | 101 |
| 2 | 108 |
| 3 | 104 |
| 4 | 115 |
| 5 | 110 |

The Real Storage measurements are:

^ Mode ^ Result ^
| **Daily Total** | 538 Volume-days |
| **Real High-Water** | 115 Volumes |
| **Real Low-Water** | 101 Volumes |

If storage is charged at $0.01 per Volume per day, the Daily Total charge is:

  538 × $0.01 = $5.38

===== Real High-Water Example =====

Real High-Water uses the highest actual Volume count recorded during the billing period.

From the previous example:

  Real High-Water = 115 Volumes

If the High-Water quantity is applied to all five days:

  115 × 5 days × $0.01 = $5.75

<WRAP note>
The Billing Rules must define whether the High-Water value is charged once or multiplied by the number of days in the billing period.
</WRAP>

===== Real Low-Water Example =====

Real Low-Water uses the lowest actual Volume count recorded during the billing period.

From the previous example:

  Real Low-Water = 101 Volumes

If the Low-Water quantity is applied to all five days:

  101 × 5 days × $0.01 = $5.05

Real Low-Water may be used to:

  * Apply a minimum storage charge.
  * Identify the Customer's base storage usage.
  * Compare minimum and maximum inventory levels.
  * Support contract-specific storage calculations.

===== Slot Total Example =====

Assume storage is allocated in blocks of 10 slots. Each daily actual inventory count is rounded up to the next block of 10.

^ Day ^ Actual Volumes ^ Billable Slots ^
| 1 | 101 | 110 |
| 2 | 108 | 110 |
| 3 | 104 | 110 |
| 4 | 115 | 120 |
| 5 | 110 | 110 |

The Slot Storage measurements are:

^ Mode ^ Result ^
| **Slot Total** | 560 slot-days |
| **Slot High-Water** | 120 slots |
| **Slot Low-Water** | 110 slots |

If storage is charged at $0.01 per slot per day, the Slot Total charge is:

  560 × $0.01 = $5.60

===== Slot High-Water Example =====

Slot High-Water uses the highest slot quantity recorded during the billing period.

From the previous example:

  Slot High-Water = 120 slots

If the Slot High-Water quantity is applied to all five days:

  120 × 5 days × $0.01 = $6.00

Slot High-Water may be used when the Customer is charged for the maximum storage capacity used during the billing period.

===== Slot Low-Water Example =====

Slot Low-Water uses the lowest slot quantity recorded during the billing period.

From the previous example:

  Slot Low-Water = 110 slots

If the Slot Low-Water quantity is applied to all five days:

  110 × 5 days × $0.01 = $5.50

Slot Low-Water may be used when the Customer is charged for a minimum level of allocated or reserved storage capacity.

===== Comparison =====

^ Mode ^ Measurement ^ Result Type ^ Typical Billing Use ^
| **Daily Total** | Sum of daily actual Volume counts. | Volume-days | Per-Volume, per-day storage billing. |
| **Real High-Water** | Highest actual inventory count. | Volumes | Maximum actual storage usage. |
| **Real Low-Water** | Lowest actual inventory count. | Volumes | Minimum actual storage usage. |
| **Slot Total** | Sum of daily slot quantities. | Slot-days | Per-slot, per-day capacity billing. |
| **Slot High-Water** | Highest slot quantity. | Slots | Maximum storage capacity used or allocated. |
| **Slot Low-Water** | Lowest slot quantity. | Slots | Minimum storage capacity used or allocated. |




===== Inventory =====

^ Term ^ Description ^
| **Inventory**            | The number of items held at a particular point in time, usually the current inventory or the inventory recorded on a specified date.                                                             |
| **Total inventory**      | The accumulated inventory across the billing period. For daily billing, this is normally the sum of each day’s inventory count and represents **item-days** rather than a single physical count. |
| **Inventory high-water** | The highest inventory count recorded at any point during the billing period. This can be used when billing the customer for their maximum storage usage.                                         |
| **Inventory low-water**  | The lowest inventory count recorded at any point during the billing period. This shows the minimum storage level and may be used for minimum-usage billing or analysis.                          |


Example

Suppose a customer’s inventory over five days is:

^ Day  ^ Inventory count  ^
| 1    | 100        |
| 2    | 110        |
| 3    | 105        |
| 4    | 120        |
| 5    | 115        |

On day 5, the Inventory is 115 Volumes.

Total Inventory, the sum of the number of Volumes over the 5 days, 550 Volume days.  Billing on the total inventory number at $0.05 per Volume per day or 550 * 0.05 = $27.50

Inventory High-water, the highest Volume daily count, 120 Volumes.  Billing off the high-water mark at $0.05 per Volume per day or 5 days * 120 * 0.05 = $30.00

Inventory Low-water, the lowest Volume daily count, 105 Volumes. Inventory low-water mark is usually used to assess the minimum amount of storage a Customer uses over a certain time frame.

The important distinction is that inventory, high-water, and low-water are point-in-time counts, while total inventory usually accumulates counts across time.


{{tag> billing}}