20 Red Hat OpenShift and IBM Cloud Paks on IBM Power Systems: Volume 1
Containers include the following key features and benefits:
/SM590000Portability:
– Single executable package with all code, configuration files, dependencies, and 
required libraries 
– Bundle must not include operating system-related files
– Open runtime engine is a prerequisite
– Common bins and libraries can be shared across multiple containers
/SM590000Agility:
– Container system is managed by Open Container Initiative
– DevOps tools and process are used for r apid code deployment by using continuous 
integration and continuous deployment (CI/CD)
– Open Source Docker engine works for Linux and Windows platforms
/SM590000Performance:
– Multiple containers share operating system  kernel for lightweight execution mode
– Improves service usage, which result s in reduced software license costs
– Container start time is much faster than VM start time
/SM590000Fault isolation:
– During concurrent execution, each container runs independently. A fault in one 
container does not affect other container’s execution. 
– Container engine takes advantage of operating system security isolation technique. 
/SM590000Ease of management:
– Container orches tration manages installation, scalability, availability as defined 
– Application version upgrade, monitoring, and debugging managed centrally through 
container orchestration system
/SM590000Security:
– Encapsulation and isolation is the firs t level of security for any containerized 
application. A rogue application does not affect other applications of the hosting 
environment
– Container engine inherits default security features from hosting platform
– Namespace provides an isolated view; for example, file system, mount point, network, 
process ID, and User ID
2.3.2  History of containers
Container seems a latest buzzword with cloud technology. However, a similar concept was 
used for the first time as early as 1970 where application code was decoupled from UNIX 
native system calls. 
Overtime, a few more enhancements were made, from stand-alone computer systems to 
integrated environments. Then, virtualization features evolved with LPAR and workload 
partition (WPAR) concepts. Although these virtualization features added flexibility, application 
portability always was a challenge. With containerization, new age software developers 
received all of the flexibility, portability, and security that they needed.