Erasure Cost Calculation
Precise Cost Calculations
For each redundancy level, there are m + k = 128 chunks, where m are the data chunks (shown in column "Data Chunks") and k are the parity chunks (shown in column "Parities"). If the number of chunks in the data being uploaded are an exact multiple of m, then the percent cost of the upload will simply equal the one shown in the chart above in the "Percent" column for the corresponding redundancy level.
Exact Multiples
For example, if we are uploading with the Strong redundancy level, and our source data consists of 321 (3 * 107) chunks, then we can simply use the percentage from the "Percent" column for the Strong level - 19.6% (63 parities / 321 data chunks).
With Remainders
However, generally speaking uploads will not come in exact multiples of m, so we need to adjust our calculations. To do so we need to use the table below which shows the number of parities for sets of chunks starting at a single chunk for each redundancy level up to the maximum number of data chunks for that level. Then we simply sum up the total parities and data chunks for the entire upload and calculate the resulting percentage.
| Security | Parities | Chunks | Percent | Chunks Encrypted | Percent Encrypted |
|---|---|---|---|---|---|
| Medium | 2 | 1 | 200% | ||
| Medium | 3 | 2-5 | 150% - 60% | 1-2 | 300% - 150% |
| Medium | 4 | 6-14 | 66.7% - 28.6% | 3-7 | 133.3% - 57.1% |
| Medium | 5 | 15-28 | 33.3% - 17.9% | 7-14 | 71.4% - 35.7% |
| Medium | 6 | 29-46 | 20.7% - 13% | 14-23 | 42.9% - 26.1% |
| Medium | 7 | 47-68 | 14.9% - 10.3% | 23-34 | 30.4% - 20.6% |
| Medium | 8 | 69-94 | 11.6% - 8.5% | 34-47 | 23.5% - 17% |
| Medium | 9 | 95-119 | 9.5% - 7.6% | 47-59 | 19.1% - 15.3% |
| Strong | 4 | 1 | 400% | ||
| Strong | 5 | 2-3 | 250% - 166.7% | 1 | 500% |
| Strong | 6 | 4-6 | 150% - 100% | 2-3 | 300% - 200% |
| Strong | 7 | 7-10 | 100% - 70% | 3-5 | 233.3% - 140% |
| Strong | 8 | 11-15 | 72.7% - 53.3% | 5-7 | 160% - 114.3% |
| Strong | 9 | 16-20 | 56.2% - 45% | 8-10 | 112.5% - 90% |
| Strong | 10 | 21-26 | 47.6% - 38.5% | 10-13 | 100% - 76.9% |
| Strong | 11 | 27-32 | 40.7% - 34.4% | 13-16 | 84.6% - 68.8% |
| Strong | 12 | 33-39 | 36.4% - 30.8% | 16-19 | 75% - 63.2% |
| Strong | 13 | 40-46 | 32.5% - 28.3% | 20-23 | 65% - 56.5% |
| Strong | 14 | 47-53 | 29.8% - 26.4% | 23-26 | 60.9% - 53.8% |
| Strong | 15 | 54-61 | 27.8% - 24.6% | 27-30 | 55.6% - 50% |
| Strong | 16 | 62-69 | 25.8% - 23.2% | 31-34 | 51.6% - 47.1% |
| Strong | 17 | 70-77 | 24.3% - 22.1% | 35-38 | 48.6% - 44.7% |
| Strong | 18 | 78-86 | 23.1% - 20.9% | 39-43 | 46.2% - 41.9% |
| Strong | 19 | 87-95 | 21.8% - 20% | 43-47 | 44.2% - 40.4% |
| Strong | 20 | 96-104 | 20.8% - 19.2% | 48-52 | 41.7% - 38.5% |
| Strong | 21 | 105-107 | 20% - 19.6% | 52-53 | 40.4% - 39.6% |
| Insane | 5 | 1 | 500% | ||
| Insane | 6 | 2 | 300% | 1 | 600% |
| Insane | 7 | 3 | 233.3% | 1 | 700% |
| Insane | 8 | 4-5 | 200% - 160% | 2 | 400% |
| Insane | 9 | 6-8 | 150% - 112.5% | 3-4 | 300% - 225% |
| Insane | 10 | 9-10 | 111.1% - 100% | 4-5 | 250% - 200% |
| Insane | 11 | 11-13 | 100% - 84.6% | 5-6 | 220% - 183.3% |
| Insane | 12 | 14-16 | 85.7% - 75% | 7-8 | 171.4% - 150% |
| Insane | 13 | 17-19 | 76.5% - 68.4% | 8-9 | 162.5% - 144.4% |
| Insane | 14 | 20-22 | 70% - 63.6% | 10-11 | 140% - 127.3% |
| Insane | 15 | 23-26 | 65.2% - 57.7% | 11-13 | 136.4% - 115.4% |
| Insane | 16 | 27-29 | 59.3% - 55.2% | 13-14 | 123.1% - 114.3% |
| Insane | 17 | 30-33 | 56.7% - 51.5% | 15-16 | 113.3% - 106.2% |
| Insane | 18 | 34-37 | 52.9% - 48.6% | 17-18 | 105.9% - 100% |
| Insane | 19 | 38-41 | 50% - 46.3% | 19-20 | 100% - 95% |
| Insane | 20 | 42-45 | 47.6% - 44.4% | 21-22 | 95.2% - 90.9% |
| Insane | 21 | 46-50 | 45.7% - 42% | 23-25 | 91.3% - 84% |
| Insane | 22 | 51-54 | 43.1% - 40.7% | 25-27 | 88% - 81.5% |
| Insane | 23 | 55-59 | 41.8% - 39% | 27-29 | 85.2% - 79.3% |
| Insane | 24 | 60-63 | 40% - 38.1% | 30-31 | 80% - 77.4% |
| Insane | 25 | 64-68 | 39.1% - 36.8% | 32-34 | 78.1% - 73.5% |
| Insane | 26 | 69-73 | 37.7% - 35.6% | 34-36 | 76.5% - 72.2% |
| Insane | 27 | 74-77 | 36.5% - 35.1% | 37-38 | 73% - 71.1% |
| Insane | 28 | 78-82 | 35.9% - 34.1% | 39-41 | 71.8% - 68.3% |
| Insane | 29 | 83-87 | 34.9% - 33.3% | 41-43 | 70.7% - 67.4% |
| Insane | 30 | 88-92 | 34.1% - 32.6% | 44-46 | 68.2% - 65.2% |
| Insane | 31 | 93-97 | 33.3% - 32% | 46-48 | 67.4% - 64.6% |
| Paranoid | 19 | 1 | 1900% | ||
| Paranoid | 23 | 2 | 1150% | 1 | 2300% |
| Paranoid | 26 | 3 | 866.7% | 1 | 2600% |
| Paranoid | 29 | 4 | 725% | 2 | 1450% |
| Paranoid | 31 | 5 | 620% | 2 | 1550% |
| Paranoid | 34 | 6 | 566.7% | 3 | 1133.3% |
| Paranoid | 36 | 7 | 514.3% | 3 | 1200% |
| Paranoid | 38 | 8 | 475% | 4 | 950% |
| Paranoid | 40 | 9 | 444.4% | 4 | 1000% |
| Paranoid | 43 | 10 | 430% | 5 | 860% |
| Paranoid | 45 | 11 | 409.1% | 5 | 900% |
| Paranoid | 47 | 12 | 391.7% | 6 | 783.3% |
| Paranoid | 48 | 13 | 369.2% | 6 | 800% |
| Paranoid | 50 | 14 | 357.1% | 7 | 714.3% |
| Paranoid | 52 | 15 | 346.7% | 7 | 742.9% |
| Paranoid | 54 | 16 | 337.5% | 8 | 675% |
| Paranoid | 56 | 17 | 329.4% | 8 | 700% |
| Paranoid | 58 | 18 | 322.2% | 9 | 644.4% |
| Paranoid | 59 | 19 | 310.5% | 9 | 655.6% |
| Paranoid | 61 | 20 | 305% | 10 | 610% |
| Paranoid | 63 | 21 | 300% | 10 | 630% |
| Paranoid | 65 | 22 | 295.5% | 11 | 590.9% |
| Paranoid | 66 | 23 | 287% | 11 | 600% |
| Paranoid | 68 | 24 | 283.3% | 12 | 566.7% |
| Paranoid | 70 | 25 | 280% | 12 | 583.3% |
| Paranoid | 71 | 26 | 273.1% | 13 | 546.2% |
| Paranoid | 73 | 27 | 270.4% | 13 | 561.5% |
| Paranoid | 75 | 28 | 267.9% | 14 | 535.7% |
| Paranoid | 76 | 29 | 262.1% | 14 | 542.9% |
| Paranoid | 78 | 30 | 260% | 15 | 520% |
| Paranoid | 80 | 31 | 258.1% | 15 | 533.3% |
| Paranoid | 81 | 32 | 253.1% | 16 | 506.2% |
| Paranoid | 83 | 33 | 251.5% | 16 | 518.8% |
| Paranoid | 84 | 34 | 247.1% | 17 | 494.1% |
| Paranoid | 86 | 35 | 245.7% | 17 | 505.9% |
| Paranoid | 87 | 36 | 241.7% | 18 | 483.3% |
| Paranoid | 89 | 37 | 240.5% | 18 | 494.4% |
Let's take our previous example and adjust it slightly. Instead of a source data consisting of 321 (3 * 107) chunks, we will add 19 chunks for a total of 340 chunks. Looking at our chart, we can see that at the Strong level for 19 data chunks we need 9 parity chunks. From this we can calculate the final percentage price: 72 / 340 = 21.17%.