## 6 Genericity: Quantitative Analysis  
This section presents the results of the quantitative analysis of the collected data in Sections 4 and 5 to determine evidence of significant differences in genericity between aspects and CO frameworks. We structure the presentation of these results in accordance with the research questions RQ4-RQ6 (see Section 1.1). A CO framework is more generic than another CO framework when it supports a higher number of common features. After all, the more features are supported, the broader the set of application and cluster configurations that can be supported and managed by a CO framework. The same measure can also be used to quantify differences in genericity between (sub)-aspects. We also take into account the number of unique features for quantifying the differences in genericity because Kubernetes has a relatively large number of unique features. Since Kubernetes is already supported by many public cloud providers and Docker EE and DC/OS also offer support for Kubernetes as an alternative orchestrator, these unique features are widely available at a large set of private and public cloud platforms. _RQ4: How are functional (sub)-aspects ranked in terms of number of common and unique features?_  
Table 3 presents an overview of the number of common and unique features found for the 9 aspects of container orchestrations. The table ranks the aspects according to the number of common feature implementation strategies by CO frameworks. We see that the functional aspects of \"application configuration and deployment\", \"application and cluster management\", \"container networking\" and \"container QoS management\" count the most common feature implementation strategies. On the other hand, the aspects of \"securing containers\", and \"resource quota management\" count the lowest number of common feature implementation strategies. Table 4 ranks the functional sub-aspects according to the number of common feature implementation implementations targeting. Again, this metric is a measure for ranking sub-aspects in terms of genericity. A first finding from Table 4 is that the sub-aspect \"persistent volumes\" counts the most common features and the most common feature implementation strategies. This is because of two reasons: \begin{table}
\begin{tabular}{l c c c} \hline \hline  & **\#Common** & **\#Implement.** & **\#Unique** \\
**Sub-aspects** & **Features** & **Strategies** & **Features** \\ \hline Persistent volumes & 9 & 47 & 6 \\ Services networking & 8 & 35 & 2 \\ Service upgrades & 8 & 32 & 1 \\ Architectural patterns & 5 & 31.5 & 0 \\ Reusable container configuration & 5 & 26 & 2 \\ Installation methods and deployment tools & 7 & 25.5 & 2 \\ Supported workload types & 7 & 25.5 & 1 \\ Cluster maintenance & 5 & 25 & 2 \\ CPU and mem allocation with support for over-subscription & 5 & 23 & 1 \\ Creation, management and inspection of cluster/applications & 4 & 22.5 & 1 \\ Service discovery and external access & 6 & 22 & 6 \\ Monitoring resource usage and health & 4 & 22 & 3 \\ Multi-cloud deployments & 5 & 19.5 & 3 \\ Controlling scheduling behavior & 3 & 19 & 0 \\ Cluster network security & 6 & 18.5 & 3 \\ Controlling preemptive (re)-scheduling behavior & 5 & 18 & 1 \\ Plugin architecture for network services & 4 & 17.5 & 0 \\ User identity and access management & 3 & 17.5 & 1 \\ Unified container runtime architecture & 3 & 17 & 0 \\ Framework design of orchestration engine & 3 & 15 & 9 \\ Logging and debugging of CO framework and containers & 3 & 15 & 1 \\ Resource quota management & 4 & 12.5 & 1 \\ Protection of sensitive data and proprietary software & 2 & 10 & 0 \\ Improved security isolation & 5 & 9.5 & 3 \\ Allocation of other resources & 2 & 9 & 4 \\ Host ports conflict management & 2 & 7.5 & 0 \\ Configuration management approach & 1 & 6 & 0 \\ Total & 124 & 548.5 & 53 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Functional sub-aspects ranked according to the number of common feature implementation strategies by CO frameworks.