The Tile-Based Mapping Transition in Cartography - Maps for the Future Children Education and Internet - page 156

Table 13.1 The number of tiles, storage requirements, and storage costs used by a tile-based
online mapping system to represent the world at different levels of detail (LOD) or zoom levels
Levels
of detail
(LOD)

Number of tiles Ground

distance per
pixel in
meters

Storage
requirements at
15 kilobytes per
tile

Disk storage
costs at $100
per terabyte

RAM memory
storage costs at
$30 per gigabyte

1 4 78,272 60 kilobytes

(KB)

$0.000006 $0.002

2 16 39,136 240 KB $0.00002 $0.007

3 64 19,568 968 KB $0.0001 $0.03

4 256 9,784 3.75 megabytes

(MB)

$0.0004 $0.11

5 1,024 4,892 15 MB $0.001 $0.44

6 4,096 2,446 60 MB $0.006 $1.76

7 16,384 1,223 240 MB $0.02 $7.03

8 65,536 611.50 960 MB $0.09 $28.13

9 262,144 305.75 3.75 gigabytes

(GB)

$0.37 $112.50

10 1,048,576 152.88 15 GB $1.46 $450.00

11 4,194,304 76.44 60 GB $5.86 $1,800.00

12 16,777,216 38.22 240 GB $23.44 $7,200.00

13 67,108,864 19.11 968 GB $93.75 $28,800.00

14 268,435,456 9.55 3.75 terabytes

(TB)

$375 $115,200.00

15 1,073,741,824 4.78 15 TB $1,500 $460,800.00

16 4,294,967,296 2.39 60 TB $6,000 $1,843,200.00

17 17,179,869,184 1.19 240 TB $24,000 $7,372,800.00

18 68,719,476,736 0.60 960 TB $96,000 $29,491,200.00

19 274,877,906,944 0.30 3.75 petabytes

(PB)

$384,000 $117,964,800.00

20 1,099,511,627,776 0.15 15 PB $1,536,000 $471,859,200.00

Total 1,466,015,503,700 20,480 terabytes

or
20 petabytes

$2,048,000 $629,145,600

computer could have this much storage capacity. A data center is required to store
this amount of data.
The cost of storing this much data on hard drives can be calculated based on a
cost of about $100 for a 1 Terabyte drive, a price that does not include the housing
or computer connection. To store the entire one trillion tiles would cost about $2
million ($100 20,480 Terabytes). In order to achieve faster response times, there
is some indication that Google uses faster random-access memory (RAM) to store
the Google map tiles. If the entire map of the world were stored in RAM, it would
cost the company more than $629 million. It is possible that only a subset of tiles are
stored with the rest being created on-the-fly based on demand.
These data storage requirements and costs are only for the map. The satellite
view, with tiles in the JPEG format, requires approximately the same amount of
storage space. A terrain view is also provided with 15 levels of detail. Google