The container revolution is upon us.\nCompanies from Red Hat to IBM, Amazon Web Services to Microsoft and even VMware are all into containers. And where there is a hot new technology, there are of course hot startups.\nIn the past year interest and buzz about containers has soared. A recent survey from research firm Forrester found that 31% of developers said they\u2019ve used Docker or containers in the past year. \u201cThat\u2019s a big number of global developers for such a new technology,\u201d says Dave Bartoletti, who tracks containers for Forrester. Another 9% say containers are already in production -- a respectable number for such a young market.\n\nFundamentally containers are a way to virtualize the\u00a0operating system to managing code and applications. There are challenges around managing containers though, from coordinating the network, to assigning storage for them. Startups from across the industry are tackling these issues and more, and here\u2019s a closer look at 12 of them.\nBlueData\nHeadquarters: Mountain ViewFounded:\u00a02012Funding:\u00a0$19 Million from Atlantic Bridge, Ignition Partners, Data Collective, Amplify Partners, Intel CapitalWhy it\u2019s worth watching: Containers are primarily seen as a way to ease application development, but some startups are finding innovative use cases for managing applications with containers. BlueData, which is led by an ex-R&D vice president from VMware named Kumar Sreekanti, is one such example.\nThe company, which aims to \u201cdemocratize\u201d big data deployments by making them more consumable, has increasingly been making containers part of its strategy. BlueData allows organizations to deploy big data platforms like Hadoop and Apache Spark in Docker containers, and is making containerized versions available through a free trial of its EPIC platform, which can run on as a downloaded program or a hosted application in Amazon Web Service\u2019s Elastic Compute Cloud (EC2). BlueData hopes to make a fuller version of its product generally available this fall.\nClusterHQ \nHeadquarters: San FranciscoFounded: 2008Funding: $15 million from Accel Partners and Canaan PartnersWhy it\u2019s worth watching: Containers don\u2019t inherently hold on to data about applications that are inside of them when they\u2019re moved from one virtual machine to another. A lot of enterprise applications need to hold on to state though. ClusterHQ\u2019s Flocker product, which is also an open source project, allows containers to hold state.\nConstellation Research analyst Holger Mueller says this is a big step forward for containers. ClusterHQ calls Flocker a data volume manager. This capability allows Docker containers to run databases in containers and port them from one VM host to another without losing data associated with the app in the container. \u201cMaking containers persistent is probably an increase of 3-5x (in terms of) uses cases that can be addressed by containers that have persistency,\u201d he wrote in a blog post analyzing the announcement of Flocker 1.0.\n+ ALSO ON NETWORK WORLD What are containers and why do you need them? +\nCoreOS \nHeadquarters: San FranciscoFounded: 2013Funding: $20 million from Google Ventures, KPCB, Fuel Capital, Accel Partners, Andreessen Horowitz, Sequoia Capital and Y-CombinatorWhy it\u2019s worth watching: The founders of CoreOS thought containers were great, but didn\u2019t love some of Docker\u2019s design decisions related to security and management. So, the CoreOS team crafted a lightweight Linux operating system meant to run in scale-out distributed systems as well as its own container software dubbed rkt (pronounced \u201crocket\u201d). Similar to the open source Docker project, rkt is a container runtime format that allows for container creation.\nCoreOS also has developed Tectonic, a commercial distribution of the Kubernetes open source container management platform from Google. If Docker will have any near-term competition from another startup, it could come from CoreOS, which was launched by Alex Polvi and Brandon Phillips, who worked on cloud monitoring at Rackspace.\nDocker \nHeadquarters: San FranciscoFounded: 2013Funding:\u00a0$150M from Insight Venture Partners, Coatue, Goldman Sachs, Northern Trust, Benchmark, Greylock Partners, Sequoia Capital, Trinity Ventures and AME Cloud Ventures.\u00a0 Why it\u2019s worth watching: There is no better recognized company in the container market right now than Docker.\nIt\u2019s the name of both an open source project for creating containers and a company that\u2019s commercializing the code. The open source project is led by a governing board that includes some Docker employees, but also contributors from many other companies. Docker has focused thus far on many of the basic aspects of containers \u2013 how to create them, how they interact with management platforms and what can be done with them. As the company advances though, it\u2019s adding more management features atop its product, for example by controlling the networking containers need. Docker \u2013 the open source code \u2013 has emerged as a de facto standard for container runtimes, which gives Docker the company a big opportunity to capitalize on commercializing the management of those containers. Solomon Hykes, Docker\u2019s CTO, is credited with helping to spur the container movement when he founded dotcloud, which was the original name of Docker the company.\nKismatic \nHeadquarters: San FranciscoFounded: 2014Funding: UndisclosedWhy it\u2019s worth watching: Google has said it runs almost all of its applications in containers, and last year open sourced software called Kubernetes that helps manage infrastructure clusters, including containers. Kismatic is a startup hoping to commercialize Kubernetes.\nAs of now the company is still in stealth mode, so details about what it is doing haven\u2019t been shared publicly. But it\u2019s expected that Kismatic will attempt to make Kubernetes more palatable to business users. That approach to open source technology usually includes things like packaging it, putting in security controls and making it reliable and fault tolerant.\nThe folks behind Kismatic come from Mesos, another orchestration technology provider. One executive served as CTO of the Wikimedia Foundation.\nPortWorx \nHeadquarters: \u00a0Redwood CityFounded:\u00a02015Funding:\u00a0 Series A round of $8.5 million, from Mayfield and one undisclosed investorWhy it\u2019s worth watching: It\u2019s one thing to be able to spin up a container, but it\u2019s a whole other thing to manage clusters of them, as Portworx wants to do.\nThink of Portworx as a sort of vSphere for containers, its founders say. The company\u2019s\n\n\t\n\ncontainer management platform gives IT operations professionals an out-of-the-box way to spin up and manage groups of containers.\nThe first thing the software does is it assess the infrastructure that is available to it. Then, when operations folks want to launch applications or code in a container, Portworx will do the heavy lifting: It will provision the containers, get the necessary storage, and manage the IP addresses and other networking features of the containers.\nThe product is a ways away from being generally available. Later this summer Portworx will release a hosted \u201cplayground\u201d version of the software, but there is no timeframe for when a 1.0 release will be generally available. Its management team previously started storage optimization company Ocarina Networks, which Dell bought in 2010.\nRancher Labs\nHeadquarters: CupertinoFounded: 2014Funding: $10M in funding from Mayfield and Nexus Venture PartnersWhy it\u2019s worth watching: The founders of Rancher - Sheng Liang and Shannon Williams - were part of the team that helped create Cloud.com \u2013 which was later sold to Citrix and is now the CloudStack product and open source cloud management product. Rancher is attempting to do for containers what CloudStack does for clouds \u2013 be a platform for managing them.\nAt this point Rancher is best known for RancherOS, a lightweight operating system optimized for running containers. The company\u2019s big plans are for its Rancher infrastructure management platform, which is in beta. It\u2019s meant to run on any virtualized or physical machine and works with applications to understand what needs they have for storage, networking and compute resources. It then allocates the appropriate infrastructure for those apps and spins up the containers to run them. Rancher currently works with Docker containers, but the company is open to supporting other container runtimes, such as CoreOS\u2019s.\nShippable \nHeadquarters: SeattleFounded: 2013Funding: $10.1 M from Madrona Venture Group, Vulcan Capital, Divergent Ventures and Founders Co-OpWhy it\u2019s worth watching: The team at Shippable wants to make it easier for developers to use containers for building applications. Containers are the perfect medium for writing, testing and launching code, they say.\nFounded by a team that used to work at Microsoft and Cloud Foundry, Shippable is a hosted service that allows developers to write code and have it be immediately tested to ensure it works and is bug-free.\nIn the past, test environments have been made up largely of virtual machines. At Microsoft, Shippable\u2019s co-founder Avi Cavale managed a multi-million dollar lab testing environment based entirely on VMs. Using Shippable, Cavale says the footprint of the testing environment can be dramatically reduced. Shippable is billed as a portion of the savings that customers realize from using containers instead of VMs.\nSysdig\u00a0\nHeadquarters: San FranciscoFounded: 2013Funding: UndisclosedWhy it\u2019s worth watching: Monitoring containers may not sound like the most exciting topic, but it\u2019s critically important. It\u2019s one thing to have containers up and running, but how many do you have? What apps are running inside of them? What other apps are those containers interacting with? Those are the types of questions that Sysdig helps answer.\nThe Linux monitoring platform is an open source project that\u2019s freely available as a download from GitHub, as well as a product from the company named Sysdig Cloud. It provides information such as system health checks, top network connections for a container, most input\/output intensive files in a container, a history of commands executed on a container, descriptions of which containers are running in a machine and what apps are running in a container. Plus it provides a sortable history of all the log data it keeps. It\u2019s accessible through a command line interface or a basic dashboard, with plans for a more polished paid version. Founder and CEO Loris Degioanni\u00a0used to work at Riverbed Technologies.\nSysdig represents one of many companies with container monitoring and tracking products; Andreessen Horowitz-backed SignalFX is another.\nTutum \nHeadquarters: Brooklyn, with another office in MadridFounded: 2013Funding: $2.65 million seed round, led by RTP Ventures with participation from Azure Capital Partners and some angel investors.Why it\u2019s worth watching: Tutum started out as a company that wanted to provide a completely hosted container environment. But its founders - a former HP technician and a Capgemini consultant - realized that hosting providers like Amazon Web Services, may offer that. So Tutum\u2019s real differentiator was not hosting containers, but the management software it built, so the company is now focused on that.\nTutum\u2019s technology has been developed with the application developer in mind. It\u2019s software is designed to allow developers to write code, port it into Tutum and let the software take care of the rest. That means Tutum will handle the network connections needed using technology called Weave. Tutum will also manage the storage those containers need and it will provide container tracking. The Tutum team hopes its product will come out of beta later this year.\nTwistlock \nFounded: 2015Headquarters: San FranciscoFunding:\u00a0$3.1M by YL ventures and angelsWhy it\u2019s worth watching: This company, founded by a team led by Ben Bernstein and Dima Stopel from Microsoft, positions its software as an \u201cend-to-end\u201d security product for protecting and monitoring containers. Twistlock provides a customizable dashboard to monitor containers in any environment, and allows what it calls \u201cgates\u201d to be put up to help control the make-up of containers.\nTwistlock also allows for security profiles to be set up so that when containers are created they follow specific guidelines. With Twistlock, users can dictate policies that restrict which apps can interact with containers, for example, and alerts can be triggered if containers are made without these security measures in place. The company name comes from the world of trade shipping containers, where twistlocks are used to secure containers to one another.\nWeaveworks\nFounded: 2014Headquarters: LondonFunding: $5 million from Accel PartnersWhy it\u2019s worth watching: Weaveworks, the company commercializing the Weave open source project, creates a virtual network that connects containers. Containers at their most basic level do not inherently have networked connections to one another.\nHaving network capabilities makes it easier to monitor and control Docker containers. Weave prescribes each container an IP address, allowing them to be mapped with its Scope tool.\nCoreOS, for example, has its own networking overlay named Rudder, which works with its rkt container runtime environment. Other platforms like Rancher and Portworx help manage network connections for containers, in addition to provisioning. Weave has focused much of its work on solving networking problems with containers, and has thus been an integral part of other container management platforms, like Tutum. Weave has recently expanded its functionality to include monitoring, visualization and management of containers. CEO Alexis Richardson came from Pivotal, while CTO Matthias Radestock co-founded messaging service RabbitMQ. The company was originally called Zettio.