# Traffic load 與 buffer size 的關係 (QoS)
Author: WhoAmI
Date: 20230126
email: kccddb@gmail.com
Copyright: CC BY-NC-SA
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input rate: $\lambda$
output rate: $\mu$


An M/M/1 queue is a stochastic process whose state space is the set {0,1,2,3,...} where the value corresponds to the number of customers in the system, including any currently in service.
Arrivals occur at rate λ according to a Poisson process and move the process from state i to i + 1.
Service times have an exponential distribution with rate parameter μ in the M/M/1 queue, where 1/μ is the mean service time.
**utilization $\rho=\frac{\lambda}{\mu}$**



:::info
當 $\rho=\lambda/\mu$ 增加 惡化更快 (通常非線性)
:::
<h2>Input Queue</h2>


<h2> Output Queue</h2>


