Containerization (computing)
{{Short description|Cloud computing concept}}
In software engineering, containerization is operating-system–level virtualization or application-level virtualization over multiple network resources so that software applications can run in isolated user spaces called containers in any cloud or non-cloud environment, regardless of type or vendor.{{cite web |last1=Scheepers |first1=Mathijs Jeroen |title=Virtualization and Containerization of Application Infrastructure: A Comparison |website=Thijs Scheepers |date=2014 |s2cid=18129086 |url=https://thijs.ai/papers/scheepers-virtualization-containerization.pdf }} The term "container" is overloaded, and it is important to ensure that the intended definition aligns with the audience's understanding. {{Cite book |title=Cloud Foundry: The Definitive Guide Develop, Deploy, and Scale |isbn=9781491932544}}{{Cite web|title=Kubernetes Documentation: Concepts: Containers|url=https://kubernetes.io/docs/concepts/containers/}}
Usage
Each container is basically a fully functional and portable cloud or non-cloud computing environment surrounding the application and keeping it independent of other environments running in parallel.{{Cite web|title=What is containerization?|url=https://www.redhat.com/en/topics/cloud-native-apps/what-is-containerization|url-status=live|access-date=2021-07-10|website=www.redhat.com|publisher=RedHat|language=en|archive-url=https://web.archive.org/web/20210508174632/https://www.redhat.com/en/topics/cloud-native-apps/what-is-containerization |archive-date=2021-05-08 }} Individually, each container simulates a different software application and runs isolated processes{{Cite web|last1=Hinck|first1=Tim Maurer, Garrett|last2=Hinck|first2=Tim Maurer, Garrett|title=Cloud Security: A Primer for Policymakers|url=https://carnegieendowment.org/research/2020/08/cloud-security-a-primer-for-policymakers?lang=en|access-date=2021-07-10|website=Carnegie Endowment for International Peace|language=en}} by bundling related configuration files, libraries and dependencies.{{Cite web|last=Rubens|first=Paul|date=2017-06-27|title=What are containers and why do you need them?|url=https://www.cio.com/article/2924995/what-are-containers-and-why-do-you-need-them.html|access-date=2021-07-10|website=CIO|language=en}} But, collectively, multiple containers share a common operating system kernel (OS).{{Cite web|title=Containerization|url=https://www.ibm.com/in-en/cloud/learn/containerization|access-date=2021-07-10|website=www.ibm.com|language=en-in}}
In recent times, containerization technology has been widely adopted by cloud computing platforms like Amazon Web Services, Microsoft Azure, Google Cloud Platform, and IBM Cloud.{{Cite web|last=December 2019|first=Jonas P. DeMuro 18|title=What is container technology?|url=https://www.techradar.com/in/news/what-is-container-technology|access-date=2021-07-10|website=TechRadar India|date=18 December 2019|language=en}} Containerization has also been pursued by the U.S. Department of Defense as a way of more rapidly developing and fielding software updates, with first application in its F-22 air superiority fighter.{{cite web |url=https://aviationweek.com/defense-space/sensors-electronic-warfare/flight-test-clears-f-22-fleet-accept-third-party-software |title=Flight Test Clears F-22 Fleet To Accept Third-Party Software |work=Aviation Week |date=30 August 2022}}
Types of containers
- OS containers
- Application containers
Security issues
- Because of the shared OS, security threats can affect the whole containerized system.
- In containerized environments, security scanners generally protect the OS, but not the application containers, which adds unwanted vulnerability.
Container management, orchestration, clustering
Container orchestration or container management is mostly used in the context of application containers.{{Cite web |title=What is Container Orchestration? Definition & Related FAQs |url=https://avinetworks.com/glossary/container-orchestration/ |access-date=2024-04-29 |website=Avi Networks}} Implementations providing such orchestration include Kubernetes and Docker swarm.
Container cluster management
Container clusters need to be managed. This includes functionality to create a cluster, to upgrade the software or repair it, balance the load between existing instances, scale by starting or stopping instances to adapt to the number of users, to log activities and monitor produced logs or the application itself by querying sensors. Open-source implementations of such software include OKD and Rancher. Quite a number of companies provide container cluster management as a managed service, like Alibaba, Amazon, Google, Microsoft.
See also
Further reading
;Journal articles:
- {{cite journal |last1=Bentaleb |first1=Ouafa |last2=Belloum |first2=Adam S. Z. |last3=Sebaa |first3=Abderrazak |last4=El-Maouhab |first4=Aouaouche |title=Containerization technologies: taxonomies, applications and challenges |journal=The Journal of Supercomputing |date=8 June 2021 |volume=78 |pages=1144–1181 |doi=10.1007/s11227-021-03914-1 |s2cid=236220833 }}
- Moreau, David; Wiebels, Kristina; Boettiger, Carl (2023). Containers for computational reproducibility. Nature Reviews Methods Primers, 3 (50). https://doi.org/10.1038/s43586-023-00236-9
- {{cite journal |last1=Watada |first1=Junzo |last2=Roy |first2=Arunava |last3=Kadikar |first3=Ruturaj |last4=Pham |first4=Hoang |last5=Xu |first5=Bing |title=Emerging Trends, Techniques and Open Issues of Containerization: A Review |journal=IEEE Access |date=2019 |volume=7 |pages=152443–152472 |doi=10.1109/ACCESS.2019.2945930 |bibcode=2019IEEEA...7o2443W |s2cid=204970781 |doi-access=free }}
- {{cite journal |last1=van den Berg |first1=Tom |last2=Siegel |first2=Barry |last3=Cramp |first3=Anthony |title=Containerization of high level architecture-based simulations: A case study |journal=The Journal of Defense Modeling and Simulation: Applications, Methodology, Technology |date=April 2017 |volume=14 |issue=2 |pages=115–138 |doi=10.1177/1548512916662365 |s2cid=64405143 |doi-access=free }}
- {{cite book |doi=10.1007/978-981-15-8411-4_4 |chapter=Containerization Design for Autonomous and Controllable Cloud Distributed System |title=Communications, Signal Processing, and Systems |series=Lecture Notes in Electrical Engineering |year=2021 |last1=Zhang |first1=Xiao |last2=Tang |first2=Yu |last3=Li |first3=Hao |last4=Liu |first4=Shaotao |last5=Lin |first5=Di |volume=654 |pages=30–38 |isbn=978-981-15-8410-7 |s2cid=236762442 }}
- {{cite book |doi=10.1007/978-3-030-24305-0_30 |chapter=Virtualization, Containerization, Composition, and Orchestration of Cloud Computing Services |title=Computational Science and Its Applications – ICCSA 2019 |series=Lecture Notes in Computer Science |year=2019 |last1=Odun-Ayo |first1=Isaac |last2=Geteloma |first2=Victor |last3=Eweoya |first3=Ibukun |last4=Ahuja |first4=Ravin |volume=11622 |pages=403–417 |isbn=978-3-030-24304-3 |s2cid=195769647 }}
;Books:
- Gabriel N. Schenker, Hideto Saito, Hui-Chuan Chloe Lee, Ke-Jou Carol Hsu, (2019) Getting Started with Containerization: Reduce the operational burden on your system by automating and managing your containers, Packt Publishing, {{ISBN|978-1-83864-903-6}}
- Jeeva S. Chelladhurai, Vinod Singh, Pethuru Raj (2014), Learning Docker, Packt Publishing, {{ISBN|978-0-9888202-0-3}}