An Analytical Framework of a Deployment Strategy for Cloud Computing Services: A Case Study of Academic Websites

Table 12

The probability distributions of request service time obtained from IFM records.

Service time (ms/request)	PDF of ED (𝐸)	PDF of RD (𝑂)	CDF of ED	CDF of RD	(𝐸−𝑂)^2/𝐸
0	0.00%	0.00%	0.00%	0.00%
[0, 13]	64.30%	74.60%	64.30%	74.60%	0.0165
(13, 26]	22.95%	18.95%	87.26%	93.55%	0.0070
(26, 39]	8.19%	4.81%	95.45%	98.36%	0.0140
(39, 52]	2.92%	1.22%	98.38%	99.58%	0.0099
(52, 65]	1.04%	0.31%	99.42%	99.89%	0.0052
(65, 78]	0.37%	0.08%	99.79%	99.97%	0.0023
(78, 91]	0.13%	0.02%	99.93%	99.99%	0.0010
(91, 104]	0.05%	0.01%	99.97%	100.00%	0.0003
(104, 117]	0.02%	0.00%	99.99%	100.00%	0.0002
(117, 130]	0.01%	0.00%	100.00%	100.00%	0.0001
(130, 143]	0.00%	0.00%	100.00%	100.00%	0.0000
(143, 156]	0.00%	0.00%	100.00%	100.00%	0.0000
(156, infinite)	0.00%	0.00%	100.00%	100.00%	0.0000
Summary					0.0564