2.1-application-http

access link utilization = 0.6 * 1.50 Mbps

0.58

1.2

0.6 * 1.50 Mbps

0.6

1.2

0.6 * 1.50 Mbps

0.4

0.9/1.54

0.58

The access link utilization can be calculated by dividing the rate at which requests are satisfied at the origin servers over the access link by the link capacity. In this case, the formula is $\text{access link utilization} = \frac{0.6 \times 1.50 , \text{Mbps}}{1.54 , \text{Mbps}}$.

The value of the access link utilization when the cache hit rate is 0.4 is 0.58. This is calculated using the formula $\text{access link utilization} = \frac{0.6 \times 1.50 , \text{Mbps}}{1.54 , \text{Mbps}}$.

The average end-to-end delay when 40% of requests are served by the cache is approximately 1.2 seconds. This is calculated using the formula $\text{average end-to-end delay} = 0.6 \times (\text{delay from origin servers}) + 0.4 \times (\text{delay when satisfied at cache})$.

The rate at which requests are satisfied at the origin servers over the access link when the cache hit rate is 0.6 is 0.9 Mbps. This is calculated using the formula $\text{rate to browsers over access link} = 0.6 \times 1.50 , \text{Mbps}$.

The average end-to-end delay when 60% of requests are served by the cache is approximately 1.2 seconds. This is calculated using the formula $\text{average end-to-end delay} = 0.6 \times (\text{delay from origin servers}) + 0.4 \times (\text{delay when satisfied at cache})$.