|By Zev Laderman||
|August 12, 2005 04:00 PM EDT||
You don't have to be around Linux for long before you hear about "the dependency problem," which is no problem at all for many users - until the day it bites them. In a nutshell, the problem is that most Linux applications depend on the operating system to provide various pieces of functionality that the applications need. These components most often take the form of shared libraries that are dynamically loaded and linked to the application at runtime. Problems occur when one or more of these libraries are replaced with a different (usually newer) version. Provided all the interfaces remain the same and the semantics of the functionality remain the same, there's no problem. However, due to security fixes, bug fixes, or new or improved functionality, the interfaces and semantics can and do change, and the changes can be enough to break the application.
In general, individual libraries aren't distributed individually but as part of a package of related components. Packages are installed as a whole. In general there's no way to take just one part of a package, and in fact to do so would be inviting trouble since packages are usually composed of related components that need to be installed as a whole to guarantee that the components work together correctly.
It would seem reasonable to assume that once an application is installed and working there would be no reason to touch it, or any of the components that it depends on. However, there are myriad reasons why components end up changing. The most common are:
- A new application is installed that requires a later version of a package containing one of the shared libraries used by the first application.
- A security or bug fix affects a package used by the application.
- An update version of the OS from the distributor includes newer packages.
This problem isn't unique to Linux. It's been a long-time problem with many different Unix systems that make heavy use of shared libraries, and is essentially the same as the famous "dll hell" that afflicted older versions of Windows (a Windows .dll file is a dynamically loaded shared library). Unix vendors reduced the problem to manageable proportions by tightly controlling the evolution of the system and providing lots of advance warning to third-party vendors of impending changes. Microsoft adopted similar tactics and became adamant about which libraries third parties were free to change, and which they weren't, making it difficult for third-party applications to overwrite system-provided libraries.
Linux is essentially no better or worse in terms of shared library management than Unix or Windows. What's different is that there's no central coordinating authority to make sure that changes happen in a controlled and consistent manner. In some respects this is one of the strengths of Open Source development; it allows change to happen at its natural pace and forces people to be more aware of the potential problems associated with change. It's also a weakness from the point-of-view of an end user having to integrate systems with components with different dependency requirements.
Linux distributors spend a lot of time and effort making sure that their systems are delivered with the dependencies all correctly resolved, and that any updates they create don't disturb this balance. They often go so far as to take security/bug/performance updates that tend to be created by the component development group on the latest version of their software - which is probably not the version currently shipping - and back-port the changes to the shipping version and test to make sure the changes don't introduce any inconsistencies. However, distributions have limited control over third parties, both commercial and Open-Source, that are reluctant to re-test their products with every new version of a package on which they have a dependency.
One of the interesting benefits Linux holds for its enterprise adopters is that it's multi-sourced. Essentially the same product is available from multiple vendors, improving competition and avoiding lock-in. Although managing multiple Linux distributions adds overhead, some companies prefer not to put all their eggs in one basket and use multiple distributions to help ensure that they don't end up locked in to a specific distribution.
However, this adds a new dimension to the dependency problem.
In many instances, different packages are used on different distributions. There's no standardized system for packaging, although most major Linux distributors use the RPM packaging system that defines how the package is constructed and what information it contains on individual file location and a set of dependency rules. Unfortunately, the same package name on two different distributions can contain different revisions of components or even different components. To add to the problem, not all Linux systems use the same package mechanism. For example, Debian-based systems don't use packages at all.
The end result is that the configuration management of these systems becomes quite complex. Applying something such as a security fix may necessitate other changes to bring the dependencies back into alignment, and then subsequent testing of all applications running on those revised systems/distributions before they can be declared stable and rolled out into production. This has to happen independently on each distribution platform.
Having lived and worked with this problem, and recognizing the need for a better solution than the mostly manual process that they and everyone else was using, the founders of Aduva began work on trying to automate the dependency resolution process.
One of the key components of their system was based on recognizing that the package level - at which most people were working - is too high a level for successful resolution. They built a database (the Aduva Universal KnowlegeBase) of dependency information based on the contents of the packages - the individual files that they contain.
By extending the dependency information and including specific dynamic dependency rules down to the file level it becomes much easier to find solutions to dependency problems. Once a set of solutions is found, information stored in the database about the composition of the packages is used to resolve the set of packages with the highest version levels possible to implement a solution. Since information is stored on distribution-specific packages, the system can derive package lists specific to individual distributions for the same dependencies.
The database also contains information on security alerts and errata notifications and fixes for packages and their components, so in building a specific package list the system takes account of these, and will find a path through the dependency graph that avoids as many of them as possible, hopefully all of them. Rarely, when re-evaluating dependencies to add a new application, the only valid path(s) will include components with known security issues. In that case the system delivers its package list, but warns that the list will introduce known security problems, leaving system administrators to decide whether to continue or consult with Aduva's Lab and professional services team to devise a solution.
Keeping the database up-to-date is the key to success. Aduva works closely with Linux distributions, many different Open Source development communities, and various security groups to ensure that it has complete and current information. A set of tools automates and tests much of the process of determining dependencies.
The complete KnowledgeBase allows systems configurations to be generated based on combinations of different packages beyond those directly supported by a given Linux distribution, provided those packages are known to the KnowledgeBase. Of course, in real-world deployments a huge variety of different applications and third-party packages are going to be encountered, more than in the centrally maintained Universal KnowledgeBase. To make sure that the extended dependency requirements encompassing these additional components are taken into account when configuring, a set of tools exists that permits individual customers to create their own KnowledgeBase with dependency rules specific to their particular software. This local KnowledgeBase is then used in conjunction with the central KnowledgeBase to ensure that the specific requirements of local software components are taken into account when determining a stable configuration.
With this core technology in place Aduva has used it as a platform on which to build a set of tools designed to simplify Linux configuration management, application deployment, change management, and patch control for the enterprise. This set of management tools is sold under the name OnStage.
The OnStage toolset provides a very complete set of system configuration management tools, enabling machine types to be defined, a configuration generated for that specific set of machines, and automatically deployed at the click of a button. Changes can be made to any given set of machines such as deploying an application, adding a patch, or changing the system configuration, and the set of changes are validated against the local and central KnowledgeBases and automatically updated to ensure dependency rules are met and pushed to the entire set of machines, either immediately, or deferred until a specific time or other criteria are met. Configurations are recorded at each stage making it trivial to back out any change or set of changes should that be required.
What's unique about the OnStage toolset is that it sits on the KnowledgeBase and takes the uncertainty out of making changes to a stable production platform, which is one more step in making Open Source a viable solution for the enterprise.
SYS-CON Events announced today that Windstream, a leading provider of advanced network and cloud communications, has been named “Silver Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place on June 9–11, 2015, at the Javits Center in New York, NY. Windstream (Nasdaq: WIN), a FORTUNE 500 and S&P 500 company, is a leading provider of advanced network communications, including cloud computing and managed services, to businesses nationwide. The company also offers broadband, phone and digital TV services to consumers primarily in rural areas.
Nov. 23, 2014 07:30 PM EST Reads: 1,677
"There is a natural synchronization between the business models, the IoT is there to support ,” explained Brendan O'Brien, Co-founder and Chief Architect of Aria Systems, in this SYS-CON.tv interview at the 15th International Cloud Expo®, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Nov. 23, 2014 12:00 PM EST Reads: 1,609
The major cloud platforms defy a simple, side-by-side analysis. Each of the major IaaS public-cloud platforms offers their own unique strengths and functionality. Options for on-site private cloud are diverse as well, and must be designed and deployed while taking existing legacy architecture and infrastructure into account. Then the reality is that most enterprises are embarking on a hybrid cloud strategy and programs. In this Power Panel at 15th Cloud Expo (http://www.CloudComputingExpo.com), moderated by Ashar Baig, Research Director, Cloud, at Gigaom Research, Nate Gordon, Director of T...
Nov. 23, 2014 07:45 AM EST Reads: 1,459
The definition of IoT is not new, in fact it’s been around for over a decade. What has changed is the public's awareness that the technology we use on a daily basis has caught up on the vision of an always on, always connected world. If you look into the details of what comprises the IoT, you’ll see that it includes everything from cloud computing, Big Data analytics, “Things,” Web communication, applications, network, storage, etc. It is essentially including everything connected online from hardware to software, or as we like to say, it’s an Internet of many different things. The difference ...
Nov. 22, 2014 10:00 PM EST Reads: 1,343
An entirely new security model is needed for the Internet of Things, or is it? Can we save some old and tested controls for this new and different environment? In his session at @ThingsExpo, New York's at the Javits Center, Davi Ottenheimer, EMC Senior Director of Trust, reviewed hands-on lessons with IoT devices and reveal a new risk balance you might not expect. Davi Ottenheimer, EMC Senior Director of Trust, has more than nineteen years' experience managing global security operations and assessments, including a decade of leading incident response and digital forensics. He is co-author of t...
Nov. 22, 2014 05:30 PM EST Reads: 1,287
ARMONK, N.Y., Nov. 20, 2014 /PRNewswire/ -- IBM (NYSE: IBM) today announced that it is bringing a greater level of control, security and flexibility to cloud-based application development and delivery with a single-tenant version of Bluemix, IBM's platform-as-a-service. The new platform enables developers to build ap...
Nov. 22, 2014 05:30 PM EST Reads: 1,452
Cloud Expo 2014 TV commercials will feature @ThingsExpo, which was launched in June, 2014 at New York City's Javits Center as the largest 'Internet of Things' event in the world.
Nov. 22, 2014 05:30 PM EST Reads: 1,439
Explosive growth in connected devices. Enormous amounts of data for collection and analysis. Critical use of data for split-second decision making and actionable information. All three are factors in making the Internet of Things a reality. Yet, any one factor would have an IT organization pondering its infrastructure strategy. How should your organization enhance its IT framework to enable an Internet of Things implementation? In his session at Internet of @ThingsExpo, James Kirkland, Chief Architect for the Internet of Things and Intelligent Systems at Red Hat, described how to revolutioniz...
Nov. 21, 2014 09:15 PM EST Reads: 1,365
Technology is enabling a new approach to collecting and using data. This approach, commonly referred to as the "Internet of Things" (IoT), enables businesses to use real-time data from all sorts of things including machines, devices and sensors to make better decisions, improve customer service, and lower the risk in the creation of new revenue opportunities. In his General Session at Internet of @ThingsExpo, Dave Wagstaff, Vice President and Chief Architect at BSQUARE Corporation, discuss the real benefits to focus on, how to understand the requirements of a successful solution, the flow of ...
Nov. 21, 2014 08:00 PM EST Reads: 1,429
The security devil is always in the details of the attack: the ones you've endured, the ones you prepare yourself to fend off, and the ones that, you fear, will catch you completely unaware and defenseless. The Internet of Things (IoT) is nothing if not an endless proliferation of details. It's the vision of a world in which continuous Internet connectivity and addressability is embedded into a growing range of human artifacts, into the natural world, and even into our smartphones, appliances, and physical persons. In the IoT vision, every new "thing" - sensor, actuator, data source, data con...
Nov. 21, 2014 08:00 PM EST Reads: 1,379
"BSQUARE is in the business of selling software solutions for smart connected devices. It's obvious that IoT has moved from being a technology to being a fundamental part of business, and in the last 18 months people have said let's figure out how to do it and let's put some focus on it, " explained Dave Wagstaff, VP & Chief Architect, at BSQUARE Corporation, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Nov. 21, 2014 07:00 PM EST Reads: 1,287
Focused on this fast-growing market’s needs, Vitesse Semiconductor Corporation (Nasdaq: VTSS), a leading provider of IC solutions to advance "Ethernet Everywhere" in Carrier, Enterprise and Internet of Things (IoT) networks, introduced its IStaX™ software (VSC6815SDK), a robust protocol stack to simplify deployment and management of Industrial-IoT network applications such as Industrial Ethernet switching, surveillance, video distribution, LCD signage, intelligent sensors, and metering equipment. Leveraging technologies proven in the Carrier and Enterprise markets, IStaX is designed to work ac...
Nov. 20, 2014 09:15 PM EST Reads: 1,374
C-Labs LLC, a leading provider of remote and mobile access for the Internet of Things (IoT), announced the appointment of John Traynor to the position of chief operating officer. Previously a strategic advisor to the firm, Mr. Traynor will now oversee sales, marketing, finance, and operations. Mr. Traynor is based out of the C-Labs office in Redmond, Washington. He reports to Chris Muench, Chief Executive Officer. Mr. Traynor brings valuable business leadership and technology industry expertise to C-Labs. With over 30 years' experience in the high-tech sector, John Traynor has held numerous...
Nov. 20, 2014 06:00 PM EST Reads: 1,333
Bit6 today issued a challenge to the technology community implementing Web Real Time Communication (WebRTC). To leap beyond WebRTC’s significant limitations and fully leverage its underlying value to accelerate innovation, application developers need to consider the entire communications ecosystem.
Nov. 20, 2014 04:45 PM EST Reads: 1,125
The 3rd International @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that it is now accepting Keynote Proposals. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago. All major researchers estimate there will be tens of billions devices - computers, smartphones, tablets, and sensors - connected to the Internet by 2020. This number will continue to grow at a rapid pace for the next several decades.
Nov. 20, 2014 01:00 PM EST Reads: 1,580
The Internet of Things is not new. Historically, smart businesses have used its basic concept of leveraging data to drive better decision making and have capitalized on those insights to realize additional revenue opportunities. So, what has changed to make the Internet of Things one of the hottest topics in tech? In his session at @ThingsExpo, Chris Gray, Director, Embedded and Internet of Things, discussed the underlying factors that are driving the economics of intelligent systems. Discover how hardware commoditization, the ubiquitous nature of connectivity, and the emergence of Big Data a...
Nov. 20, 2014 12:30 PM EST Reads: 1,790
Almost everyone sees the potential of Internet of Things but how can businesses truly unlock that potential. The key will be in the ability to discover business insight in the midst of an ocean of Big Data generated from billions of embedded devices via Systems of Discover. Businesses will also need to ensure that they can sustain that insight by leveraging the cloud for global reach, scale and elasticity.
Nov. 18, 2014 09:00 PM EST Reads: 2,015
SYS-CON Events announced today that IDenticard will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. IDenticard™ is the security division of Brady Corp (NYSE: BRC), a $1.5 billion manufacturer of identification products. We have small-company values with the strength and stability of a major corporation. IDenticard offers local sales, support and service to our customers across the United States and Canada. Our partner network encompasses some 300 of the world's leading systems integrators and security s...
Nov. 18, 2014 08:15 PM EST Reads: 1,567
IoT is still a vague buzzword for many people. In his session at @ThingsExpo, Mike Kavis, Vice President & Principal Cloud Architect at Cloud Technology Partners, discussed the business value of IoT that goes far beyond the general public's perception that IoT is all about wearables and home consumer services. He also discussed how IoT is perceived by investors and how venture capitalist access this space. Other topics discussed were barriers to success, what is new, what is old, and what the future may hold. Mike Kavis is Vice President & Principal Cloud Architect at Cloud Technology Pa...
Nov. 18, 2014 01:30 PM EST Reads: 2,008
Cloud Expo 2014 TV commercials will feature @ThingsExpo, which was launched in June, 2014 at New York City's Javits Center as the largest 'Internet of Things' event in the world. The next @ThingsExpo will take place November 4-6, 2014, at the Santa Clara Convention Center, in Santa Clara, California. Since its launch in 2008, Cloud Expo TV commercials have been aired and CNBC, Fox News Network, and Bloomberg TV. Please enjoy our 2014 commercial.
Nov. 13, 2014 05:00 AM EST Reads: 3,543