My discussion with ChatGPT-4 about the evolution of the Internet

Last update : December 17, 2023

In mid-2013, I published my contribution Divide the Web Timeline in nine epochs on my website and in different Internet forums. Today, I discussed this topic with ChatGPT-4 and I am impressed with the high quality of the chat. Here is the flow of our dialogue :

I created the following timeline for the Internet history:

No VersionTime periodDurationEpoch
1Web 01930 – 1969 40 years Internet pre-history
2Web 0.51970 – 198920 yearsInternet (network) history
3Web 11990 – 199910 yearsread-only web
4Web 1.52000 – 20045 yearsinteractive web
5Web 22005 – 20095 yearscollaborative web
6Web 2.52010 – mid 20122,5 yearsmobile web
7Web 3 mid 2012 – 20142,5 yearssemantic web
8Web 3.52015 – mid 20172,5 yearsintelligent web
9Web 4mid 2017 – 20192,5 yearsconscious web

Your timeline provides an interesting perspective on the evolution of the Internet, categorized into different “Web” versions. Let’s briefly discuss each phase:

  1. Web 0 (1930 – 1969, Internet pre-history): This period predates the actual development of the Internet. It’s interesting that you’ve included it, as it may refer to the foundational technologies and theories that later enabled the creation of the Internet, such as early computing and networking concepts.
  2. Web 0.5 (1970 – 1989, Internet network history): This era likely refers to the development of the initial networking infrastructure, including the birth of ARPANET in 1969, which is considered the predecessor of the modern Internet.
  3. Web 1.0 (1990 – 1999, read-only web): This is the period of the early World Wide Web, where websites were mostly static and offered limited interaction. Users could read information on web pages but had minimal ways to interact or contribute content.
  4. Web 1.5 (2000 – 2004, interactive web): Here, we see the emergence of more interactive websites. This could include the early stages of e-commerce, online forums, and more dynamic content.
  5. Web 2.0 (2005 – 2009, collaborative web): This is characterized by the growth of social media, user-generated content, and increased interactivity. It represents a shift from static web pages to dynamic and shareable content.
  6. Web 2.5 (2010 – mid 2012, mobile web): The focus here is on the adaptation of the web for mobile devices. The rise of smartphones and tablets during this period greatly influenced web design and accessibility.
  7. Web 3.0 (mid 2012 – 2014, semantic web): This phase is often associated with the concept of the “semantic web”, where data is interconnected in a way that can be easily understood and utilized by machines, enhancing personalization and context-aware computing.
  8. Web 3.5 (2015 – mid 2017, intelligent web): This could refer to advancements in artificial intelligence and machine learning, leading to more intelligent and adaptive web services.
  9. Web 4.0 (mid 2017 – 2019, conscious web): This term is less commonly used and could refer to an envisioned future state of the Internet, possibly involving more advanced AI, deeper integration with daily life, and perhaps even elements of consciousness or highly advanced interactivity.

Your timeline is an innovative way to categorize the development of the Internet, though some of these terms (like Web 3.5 and Web 4.0) are not widely recognized in the same way as Web 1.0 or Web 2.0. It’s a subjective interpretation, but a very interesting one!

Please suggest one innovator which you consider the most influential for each epoch.

Selecting the most influential innovator for each epoch of the Internet’s history is a challenging task, as each period saw contributions from many exceptional individuals. However, I’ll suggest one key figure for each epoch, bearing in mind that this is a subjective selection and there are many other equally significant contributors:

  1. Web 0 (1930 – 1969, Internet pre-history):
    • Claude Shannon: Known as the “father of information theory,” Shannon’s work laid the foundational principles for digital circuit design theory and telecommunications, which were crucial for the development of the Internet.
  2. Web 0.5 (1970 – 1989, Internet network history):
    • Vint Cerf and Robert Kahn: Often regarded as the “fathers of the Internet,” Cerf and Kahn co-invented the TCP/IP protocols, which are the foundational technology protocol suite for the Internet.
  3. Web 1.0 (1990 – 1999, read-only web):
    • Tim Berners-Lee: He invented the World Wide Web, a key development that made the Internet accessible and useful to the general public.
  4. Web 1.5 (2000 – 2004, interactive web):
    • Marc Andreessen: As the co-author of Mosaic, the first widely used web browser, and the co-founder of Netscape, Andreessen significantly contributed to making the web more interactive and user-friendly.
  5. Web 2.0 (2005 – 2009, collaborative web):
    • Mark Zuckerberg: As the co-founder of Facebook, Zuckerberg played a pivotal role in the rise of social media and the shift towards a more collaborative, user-generated web.
  6. Web 2.5 (2010 – mid 2012, mobile web):
    • Steve Jobs: While not directly an Internet innovator, Jobs’ work with Apple in popularizing the iPhone significantly influenced how the Internet was accessed and used on mobile devices.
  7. Web 3.0 (mid 2012 – 2014, semantic web):
    • Tim Berners-Lee (again): His continued work and advocacy for a more semantic, data-driven web are significant for this era.
  8. Web 3.5 (2015 – mid 2017, intelligent web):
    • Jeff Dean and Sanjay Ghemawat: Their work at Google, particularly on systems like MapReduce and Google Brain, contributed greatly to the development of AI and machine learning technologies that underpin the intelligent web.
  9. Web 4.0 (mid 2017 – 2019, conscious web):
    • Elon Musk: Through his work with Neuralink and his advocacy for AI, Musk has been a driving force in discussions around the convergence of technology, consciousness, and the Internet, though this era is still emerging and somewhat speculative.

Each of these figures represents just a part of the collaborative efforts and innovations that have shaped the Internet’s history.

Please generate a diagram of this timeline.

Visualization of my Internet Timeline generated by ChatGPT-4

Here is the timeline diagram of the Internet’s history, as per your request. This visualization represents the various epochs from 1930 to 2019, detailing the transitions from Web 0 to Web 4.0. You can view each phase along with its corresponding time period and description.

Thank you, but the text is not readable. Please generate a new one.

Second visualization of my Internet Timeline generated by ChatGPT-4

Here is the revised timeline diagram of the Internet’s history, designed for better readability. This visualization clearly represents the various phases from Web 0 to Web 4.0, covering the period from 1930 to 2019.

Please create a diagram for the nine epochs in the style of this image:

My Web Timeline in 9 epochs
Third visualization of my Internet Timeline generated by ChatGPT-4

Here is the diagram for the nine epochs of the Internet’s history, styled similarly to the image you provided. It presents a visual progression of the web from 1930 to 2019 with each epoch labeled and color-coded

Please suggest 10 pioneers for each period.

Certainly! Here’s a list of 10 pioneers for each epoch of Internet history, keeping in mind that these are just a few among many who have contributed significantly:

Web 0 (1930 – 1969, Internet pre-history)

  1. Claude Shannon: Father of information theory.
  2. Alan Turing: Pioneer of theoretical computer science.
  3. John von Neumann: Key figure in the development of early computers.
  4. Paul Baran: Innovator of packet switching, fundamental to Internet data transmission.
  5. Donald Davies: Co-inventor of packet-switched networks.
  6. J.C.R. Licklider: Early visionary of a global computer network.
  7. Norbert Wiener: Founder of cybernetics.
  8. Vanavar Bush: Developer of the Memex concept, an early vision of the web.
  9. Leonard Kleinrock: Developed the mathematical theory of packet networks.
  10. Herbert Simon: His work in AI and computing was foundational.

Web 0.5 (1970 – 1989, Internet network history)

  1. Vint Cerf and Robert Kahn: Co-inventors of the TCP/IP protocols.
  2. Ray Tomlinson: Creator of email.
  3. Bob Metcalfe: Inventor of Ethernet technology.
  4. Paul Mockapetris: Inventor of the Domain Name System (DNS).
  5. Radia Perlman: Known for her work on network bridging and the Spanning Tree Protocol.
  6. Tim Paterson: Developer of DOS, critical for early personal computers.
  7. Ken Thompson and Dennis Ritchie: Creators of UNIX, which influenced many modern operating systems.
  8. Jon Postel: Key figure in the development and governance of the early Internet.
  9. Steve Wozniak: Co-founder of Apple, influential in personal computer revolution.
  10. Richard Stallman: Advocate for free software movement and founder of the GNU Project.

Web 1.0 (1990 – 1999, read-only web)

  1. Tim Berners-Lee: Inventor of the World Wide Web.
  2. Marc Andreessen: Co-author of Mosaic, the first widely used web browser.
  3. Eric Bina: Co-developer of Mosaic.
  4. Roberta Williams: Influential in graphical adventure games, expanding the web’s use.
  5. Rasmus Lerdorf: Creator of PHP, widely used in web development.
  6. Brendan Eich: Creator of JavaScript, essential for web interactivity.
  7. Larry Page and Sergey Brin: Co-founders of Google, transforming web search and usage.
  8. David Filo and Jerry Yang: Founders of Yahoo, pioneers in web portals.
  9. Matt Drudge: Creator of the Drudge Report, influential in online news and media.
  10. Pierre Omidyar: Founder of eBay, pioneering e-commerce.

Web 1.5 (2000 – 2004, interactive web)

  1. Jeff Bezos: Founder of Amazon, significantly expanded the scope of e-commerce.
  2. Jack Ma: Founder of Alibaba, major figure in global e-commerce.
  3. Jimmy Wales: Co-founder of Wikipedia, exemplifying user-generated content.
  4. Chad Hurley, Steve Chen, and Jawed Karim: Founders of YouTube, changing how video is shared online.
  5. Mark Zuckerberg: Founder of Facebook, influential in social networking.
  6. Reid Hoffman: Founder of LinkedIn, pioneering professional networking.
  7. Tom Anderson: Co-founder of MySpace, an early popular social media site.
  8. Ben Silbermann: Creator of Pinterest, influential in image-sharing and curation.
  9. Evan Williams: Co-founder of Blogger, popularizing blog publishing.
  10. Kevin Systrom: Co-founder of Instagram, influential in mobile photo sharing.

Web 2.0 (2005 – 2009, collaborative web)

  1. Jack Dorsey: Co-founder of Twitter, influential in microblogging.
  2. Jan Koum and Brian Acton: Founders of WhatsApp, changing instant messaging.
  3. Daniel Ek: Founder of Spotify, pioneering in music streaming.
  4. Stewart Butterfield: Co-founder of Flickr, important in photo sharing.
  5. Markus Persson: Creator of Minecraft, influential in gaming and online communities.
  6. Travis Kalanick: Co-founder of Uber, transforming transportation services.
  7. Brian Chesky: Co-founder of Airbnb, influential in peer-to-peer lodging.
  8. Drew Houston: Founder of Dropbox, pioneering cloud storage and sharing.
  9. Hiroshi Mikitani: Founder of Rakuten, expanding e-commerce in Asia.
  10. Mike Krieger: Co-founder of Instagram, significant in social media evolution.

Web 2.5 (2010 – mid 2012, mobile web)

  1. Steve Jobs: Co-founder of Apple, pivotal in the mobile internet revolution.
  2. Andy Rubin: Co-founder of Android, influential in mobile operating systems.
  3. Jeff Lawson: Founder of Twilio, important in cloud communications.
  4. Evan Spiegel: Co-founder of Snapchat, influential in ephemeral messaging.
  5. Lei Jun: Founder of Xiaomi, significant in smartphone and IoT device manufacturing.
  6. Travis Kalanick and Garrett Camp: Founders of Uber, reshaping mobile transportation services.
  7. Sean Rad: Co-founder of Tinder, influential in mobile dating apps.
  8. John Hanke: Founder of Niantic, known for Pokémon Go, pioneering AR in mobile gaming.
  9. Nick D’Aloisio: Founder of Summly, notable for AI in news aggregation on mobile.
  10. Daniel Ek (again): His work with Spotify on mobile platforms.

Web 3.0 (mid 2012 – 2014, semantic web)

  1. Tim Berners-Lee: Continued to be influential in pushing for a more interconnected and semantic web.
  2. Jeff Dean: A Google Senior Fellow, significant in developing large-scale AI systems.
  3. Elon Musk: Founder of SpaceX and Tesla, influential in integrating web technologies in new domains.
  4. Larry Page (again): His work in integrating AI into Google’s services.
  5. Reed Hastings: Co-founder of Netflix, pioneering content streaming and personalization.
  6. Marc Benioff: Founder of Salesforce, a leader in cloud computing and CRM.
  7. Marissa Mayer: Former CEO of Yahoo, influential in web services and search.
  8. Satya Nadella: CEO of Microsoft, significant in cloud computing and AI integration.
  9. Sundar Pichai: CEO of Google, influential in AI and cloud computing.
  10. Sheryl Sandberg: COO of Facebook, instrumental in business strategy for social media.

Web 3.5 (2015 – mid 2017, intelligent web)

  1. Jeff Dean (again): His continued work in Google Brain and AI.
  2. Sundar Pichai (again): Leading Google’s AI-first approach.
  3. Demis Hassabis: Co-founder of DeepMind, a pioneer in artificial intelligence.
  4. Elon Musk (again): His work in AI and Neuralink.
  5. Mark Zuckerberg (again): For integrating AI into Facebook’s platforms.
  6. Satya Nadella (again): His leadership in Microsoft’s AI initiatives.
  7. Susan Wojcicki: CEO of YouTube, important in AI-driven video recommendations.
  8. Ginni Rometty: Former CEO of IBM, influential in Watson AI.
  9. Yann LeCun: Facebook’s AI Research Director, a key figure in deep learning.
  10. Fei-Fei Li: An AI professor and advocate for ethical AI.

Web 4.0 (mid 2017 – 2019, conscious web)

  1. Elon Musk (again): For his vision regarding AI and the future of technology integration.
  2. Jeff Bezos (again): His work with Amazon and Alexa in integrating AI into everyday life.
  3. Mark Zuckerberg (again): For exploring AI and VR integration in social media.
  4. Sundar Pichai (again): For leading Google’s advancements in AI and quantum computing.
  5. Tim Cook: CEO of Apple, continuing to integrate AI and advanced technologies in products.
  6. Ginni Rometty (again): For IBM’s advances in AI and quantum computing.
  7. Satya Nadella (again): For Microsoft’s advancements in AI, cloud computing, and mixed reality.
  8. Masayoshi Son: CEO of SoftBank, significant in investing in AI and robotics.
  9. Reed Hastings (again): For Netflix’s use of AI in content personalization and recommendation.
  10. Lei Jun (again): His work in integrating AI and IoT in Xiaomi’s products.

Each of these periods had numerous contributors, and the ones listed above played key roles in shaping the Internet’s evolution. Remember, this list is not exhaustive, and many more innovators have had a significant impact.

What about Giulio Tononi ?

Giulio Tononi is a prominent neuroscientist and psychiatrist, widely known for his work in consciousness studies, particularly for his development of the Integrated Information Theory (IIT). Tononi’s contributions, however, are primarily in the field of neuroscience and the theoretical study of consciousness, rather than directly in the development or evolution of the Internet or its technologies.

Integrated Information Theory proposes a framework to scientifically measure how conscious a system is and suggests that consciousness is a fundamental aspect of physical reality. This theory has significant implications in various fields, including psychology, neuroscience, philosophy, and potentially artificial intelligence and robotics. It provides insights into understanding the nature of consciousness, which could influence the development of AI and potentially, in a broader sense, aspects of Web 4.0, particularly those exploring the intersection of AI, consciousness, and technology.

While Tononi’s work is influential and groundbreaking, it doesn’t directly correlate with the development of Internet technology or its various epochs as outlined in your timeline. His contributions are more aligned with theoretical and philosophical understandings of consciousness, which may indirectly influence future technological developments, particularly in areas like AI and human-computer interaction.

In your proposal of Internet pioneers for the 9 epochs, who is the global outstanding innovator ?

Selecting a single “global outstanding innovator” across the entire history of the Internet is exceptionally challenging because the development of the Internet is a cumulative effort of countless individuals, each building upon the work of others. However, if we were to choose one individual whose work has had a profound and foundational impact across multiple eras of the Internet, Tim Berners-Lee stands out as a particularly influential figure.

Tim Berners-Lee is often credited with inventing the World Wide Web in 1989, which revolutionized how the Internet was used and made it accessible to the general public. His creation of the first web browser and the technologies that underpin the web (HTML, HTTP, URLs) laid the groundwork for the explosive growth of the Internet during the Web 1.0 era. Moreover, his ongoing advocacy for a free and open Internet, his efforts to enhance web standards, and his vision for the Semantic Web (Web 3.0) have continued to influence the evolution of the Internet. His contributions are not confined to a single epoch but have rippled through the entire timeline of the Internet’s development.

Berners-Lee’s dedication to ensuring that the web remains a universally accessible and neutral platform also reflects the collaborative and international spirit in which the Internet was conceived and has continued to evolve. Thus, while many innovators have made indispensable contributions, Berners-Lee’s impact has been uniquely broad and enduring.

Please propose the next epochs to extend the timeline after 2020.

Predicting the future of the Internet is speculative, but it’s an intriguing exercise to imagine how current trends might evolve. Building on the previous epochs, here’s a possible extension of the timeline beyond 2020, reflecting current technological advancements and anticipated future developments:

  1. Web 4.5 (2020 – 2024, Integrated Web): This period could see the integration of the Internet more deeply into daily life through the Internet of Things (IoT), where everyday objects become interconnected and smart. Advances in AI continue to enable more personalized and context-aware experiences.
  2. Web 5.0 (2025 – 2029, Immersive Web): Virtual reality (VR) and augmented reality (AR) could become mainstream, leading to an immersive Internet experience where digital and physical realities blend seamlessly. This could also be the era of the spatial web, where web services are integrated into the three-dimensional space around us.
  3. Web 5.5 (2030 – 2034, Quantum Web): With quantum computing reaching maturity, this epoch may herald unprecedented computational powers, leading to breakthroughs in cryptography, data processing, and an overall leap in the capabilities of the Internet, potentially affecting everything from search algorithms to AI.
  4. Web 6.0 (2035 – 2040, Autonomous Web): The rise of autonomous systems, powered by sophisticated AI and machine learning algorithms, could create a self-organizing Internet. This might involve autonomous data centers, self-repairing networks, and AI-driven content creation and curation.
  5. Web 6.5 (2041 – 2045, Symbiotic Web): This could be the age of bio-digital convergence, where the boundary between digital and biological systems blurs. Advances in bioinformatics and neurotechnology might enable direct brain-computer interfaces, leading to an Internet experience that is directly “felt” or experienced without screens or devices.
  6. Web 7.0 (2046 – 2050, Cognitive Web): AI may evolve to understand and interpret human emotions and cognitive states, leading to an empathetic Internet that can adapt to the emotional and psychological needs of users. This could also involve cognitive assistants that understand and augment human thought processes.
  7. Web 7.5 (2051 – 2055, Holistic Web): In this epoch, the Internet might evolve into a holistic global brain, connecting all human knowledge and experience in a central, accessible network that not only connects people but also provides insights and understanding at a global scale.
  8. Web 8.0 (2056 – 2060, Interstellar Web): Looking further into the future, the Internet could expand beyond Earth, connecting human settlements on other planets and spacecraft, leading to an interstellar network that serves not just a global community but a multi-planetary civilization.

These future epochs represent an extrapolation of current technological trends into the future and are speculative by nature. They reflect the potential for technological convergence, where different streams of innovation merge to create transformative changes in the way the Internet is experienced and utilized.

I think the duration of an epoch will decrease exponentially.

That’s an interesting observation and it aligns with the concept of accelerating change, where the rate of technological progress increases exponentially over time. This is often associated with Moore’s Law, which originally referred to the doubling of transistors on integrated circuits approximately every two years, but has also been generalized to the rapid pace of technological and computational advances.

Given this concept, future epochs of the Internet might indeed have shorter durations as innovations occur more rapidly.

Based on your proposals, my suggestion is the following:

10Web 4.52020 – mid 20211,5 yearsadaptive web
11Web 5mid 2021 – 20231,5 yearsubiquitus web
12Web 5.52024 1 yeardecentralized web
13Web 620251 yearquantum web
14Web 6.520261 yearautonomous web
15Web 720271 yearcognitive web
16Web 7.520281 yearsymbiotic web
17Web 820291 yearholistic web
18Web 8.5> 2030?interstellar web

Your proposed timeline reflects an accelerated pace of change and represents a vision of the Internet’s evolution that is both ambitious and intriguing. Each epoch you’ve described encapsulates a significant technological shift or integration of the Internet into broader aspects of life and society:

  1. Web 4.5 (2020 – mid 2021, Adaptive Web): Focused on AI-driven personalization, where algorithms adapt to individual behaviors and preferences.
  2. Web 5.0 (mid 2021 – end 2023, Ubiquitous Web): Marked by the Internet’s integration into daily life through IoT, making connectivity seamless and omnipresent.
  3. Web 5.5 (2024, Decentralized Web): Characterized by blockchain technologies that enable a shift to decentralized networks, enhancing user control over data.
  4. Web 6.0 (2025, Quantum Web): Quantum computing impacts the Internet, potentially revolutionizing data security, processing, and overall performance.
  5. Web 6.5 (2026, Autonomous Web): AI systems manage much of the web’s functionality, leading to self-organizing networks and content management.
  6. Web 7.0 (2027, Cognitive Web): Advances in neurotechnology allow for direct brain-computer interfaces, enabling thought-driven interaction with the web.
  7. Web 7.5 (2028, Symbiotic Web): Digital and biological systems begin to merge, leading to enhanced human capabilities and bio-digital networks.
  8. Web 8.0 (2029, Holistic Web): The Internet evolves into a global brain, connecting humanity in a shared network of knowledge and consciousness.
  9. Web 8.5 (> 2030, Interstellar Web): Expansion beyond Earth, with the Internet connecting humans across planets and possibly even interstellar distances.

This timeline serves as a speculative roadmap for how the Internet might develop, highlighting transformative changes that could redefine human interaction, commerce, and connectivity. While it is a projection, it’s a thought-provoking look at the potential future of digital and human convergence.

I have a last wish: please generate an image which includes Web 4.5 up to Web 8.5.

Here is the futuristic diagram illustrating the evolution of the Internet from Web 4.5 to Web 8.5, with each epoch represented by unique icons and themes that symbolize the main characteristics of that period.

I don’t like the diagram, I prefer a futuristic artistic image.

Here is the futuristic artistic representation that conceptualizes the evolution of the Internet from Web 4.5 to Web 8.5. The image features abstract elements and visual metaphors that symbolize the main themes of each epoch, connected in a progressive flow.

Great. Thank you very much !

I’m glad you liked it! If you have any more requests or need further assistance, feel free to ask. Good luck with your timeline project!


Operation of ChatGPT-4

In daily newspapers, some journalists continue to explain that a chatbot is a language model derived from a statistical analysis of the distribution of words in pre-existing texts. I am of the opinion that the relevance of the answers provided by ChatGPT-4 proves that conversational artificial intelligence is based on mechanisms other than algorithms using statistics.

Internet Pioneers

Even if the list of 83 Internet pioneers, proposed by ChatGPT-4, includes only 6 women, I fully endorse the selection made. I also agree that Tim Berners-Lee, who has chaired the World Wide Web Consortium (W3C) since 1994, is the most deserving figure among Internet innovators.

Internet timeline

ChatGPT-4’s proposal to extend the segmentation of Internet evolution beyond 2020 is very cautious, while my own suggestion, approved by ChatGPT-4, is very ambitious. I think the most likely forecast lies somewhere in the middle.

Weaknesses of ChatGPT-4

While the generation of artistic images by ChatGPT-4 is exemplary, the creation of technical drawings or diagrams is not yet one of its strengths. The integration of letters and words into an image does not yet conform to the rules. Furthermore, ChatGPT-4 needs to perfect its mastery of numbers in relation to the generation of illustrations and the recognition of objects in images. The following screenshots show that ChatGPT-4 has made efforts in drawing geometric shapes, but it does not yet have the skills to properly manage numbers.

DICOM Testing with DVTk

Last update : January 10, 2020

DVTk history

DVTk is an open source project for testing, validating and diagnosing communication protocols and scenarios in medical environments. It supports DICOM and IHE integration profiles. The project started in 1997 by Philips and was joined by Agfa in 2001. In 2005, DVTk was open sourced and one year later ICT Automatisering joined the open source community. In 2009 Agfa left the project.

The following tools are currently free available from the website or from GitHub :

  • DICOM Compare, v 5.0.0
  • DICOM Editor, v 5.0.2
  • DICOM Network Analyzer, v 5.0.1
  • DVT Validator, v 5.0.3
  • Query Retrieve SCP Emulator, v 5.0.1
  • RIS Emulator, v 5.0.0
  • Storage SCP Emulator, v 5.0.2
  • Storage SCU Emulator, v 5.0.1

DVTk Tests

I used these tools in the context of the development of an education tool for radiologists called RadioLogic. I edited the following script to execute an ECHO test and a STORE-SCP test with the Orthanc DICOM Server, version 0.9.5 :

# DVT Dicom Script
# Product Test Session Properties
SESSION-TITLE "Orthanc Server"
MANUFACTURER "Manufacturer"
MODEL-NAME "Product Name"
TESTED-BY "Marco Barnig"
DATE "20151208"
# SUT ACSE Properties
SUT-ROLE acceptor
# DVT ACSE Properties
DVT-IMPLEMENTATION-CLASS-UID "1.2.826.0.1.3680043.2.1545.1"
# Socket Properties
SUT-HOSTNAME "localhost"
# Test Session Properties
PDU-DUMP false
# Supported Transfer Syntaxes
SUPPORTED-TRANSFER-SYNTAX "1.2.840.10008.1.2.2"
SUPPORTED-TRANSFER-SYNTAX "1.2.840.10008.1.2.1"
# Configurable Delay between N-Action and N-Event Command
# Definitions
DEFINITION "All DIMSE Commands.def"
DEFINITION "CT Image Storage.def"
DEFINITION "Digital X-Ray Image Storage - For Presentation.def"
DEFINITION "Digital X-Ray Image Storage - For Processing.def"
DEFINITION "Enhanced CT Image Storage.def"
DEFINITION "Enhanced MR Image Storage.def"
DEFINITION "Media Storage Directory.def"
DEFINITION "MR Image Storage.def"
# Results
RESULTS-ROOT ".\results\"
# DICOMScript Description Directory

Scripts are saved as text files with the extension .ses. Several scripts can be referenced in an xml-project file with the extension .pdvt.

The following figure shows the resulting settings in the DVTk session panel :


DTVk DICOM validator session panel

By double-clicking on the Storage-SCU-emulator link at the left, a window pops up allowing to do an ECHO test or to send a DICOM file to the Orthanc server. The exchanged messages are displayed in the Activity Logging panel :


DVTk Activity Logging

After the succesful sending of a DICOM file to the Orthanc server, a summary of the validation results is shown in the Validation Results panel :


DVTk Validation Results

In verbose mode, the Orthanc Server provides the following releated messages in the command window :

Orthanc Server output in verbose mode

Orthanc Server output in verbose mode

DVTk Network Sniffer

The next figure shows the results of the DVTk network sniffer analyzing the DICOM traffic between the OSIRIX HD viewer on iPad with the ORTHANC DICOM server (version 0.9.6) running on Window 8.1.


DVTk summary results of FIND Request sent by Osirix HD from iPad

I entered only the first characters of the patient name to send a FIND query. DVTk reports four errors in the C-FIND communication because the following data elements are not valid :

  • (0008, 0018) : SOP Instance UID > should be present with at least a zero length
  • (0010, 0020) : Patient ID > should be present with at least one value
  • (0020, 000D) : Study Instance UID > should be present with at least one value
  • (0020, 000E) : Series Instance UID > should be present with at least one value

The C-MOVE communication works without errors and the received results displayed in Osirix HD are correct.


DVTk reports no errors in the C-MOVE communication between Osirix HD and Orthanc

The Orthanc server shows no specific error message in the command window.

The OSIRIX HD viewer is configured as follows :

  • Remote AET : ORTHANC
  • IP :
  • Port : 4242
  • AETitle : OSIRIXHD
  • IP :
  • Port : 4096
  • Transfer Syntax : Implicit Little Endian (preferred syntax by Orthanc)
  • Encoding : ISO IR 100 (Latin-1)
  • Protocol : C-MOVE
  • Timeout : 90 sec

Communication Failure

The next example shows the case of a failed communication. The C-FIND query sent by the PACS DICOM iPad app to the Orthanc server (version 0.9.6) is aborted with a DIMSE failure. The query is identical to the C-FIND request sent by Osirix HD. The Orthanc log signals “DIMSE No data available (timeout in none-blocking mode)”.


Orthanc log messages related to a C-FIND command sent by the PACS DICOM app

The DVTk network analyzer shows the same four errors as in the case of the Osirix communication. After a timeout, the communication is aborted.


DVTk signals an Abort Request in the PACS DICOM – Orthanc association

The PACS DICOM viewer is configured as follows :

  • Server AET : ORTHANC
  • Host Name/IP :
  • Server Port : 4242
  • Local AET : TEST-SCU
  • Device IP Address :
  • Local Port : 4096
  • Protocol : C-MOVE

A deeper analysis is required to identify the reason of the abort request. If the problem is caused by a non-valid parameter in the C-FIND query, the recently proposed LUA script filter will be an excellent remedy.

Accessing Local Virtual Hosts

Last update : September 7, 2015

Local Networks

A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, or office building. It is contrasted to a wide area network (WAN), which covers a larger geographic distance and may involve leased telecommunication circuits. Ethernet over twisted pair cabling and Wi-Fi (WLAN) are the two most common transmission technologies in use for local area networks.

Virtual Hosts

The term Virtual Host refers to the practice of running more than one website (such as and on a single machine. The fact that they are running on the same physical server is not apparent to the end user. Apache was one of the first servers to support virtual hosts right out of the box.

Computer Name, Address and Route

To find and access a computer in an network, we must know the following informations :

  1. Name : to indicate what we seek ( > Domain Name )
  2. Address : to indicate where it is ( > IP Address )
  3. Route : to indicate how to get there ( > Routing )

Domain Name

Domain names are used to identify one or more IP addresses. They are used in URLs to identify particular web pages. Domain names can be local or public. The latter must be registered with an ICANN accredited registrar.

A domain name consists of one or more parts, technically called labels, that are conventionally concatenated, and delimited by dots, such as The right-most label conveys the top-level domain (TLD), including the generic top-level domains (gTLDs), such as the prominent domains com, info, net, edu, and org, and the country code top-level domains (ccTLDs) such as lu, de, fr.

Below the top-level domains in the domain name hierarchy are the second-level domain (SLD) names. These are the names directly to the left of the top-level domains. Second-level domain names are usually created based on the name of a company, product or service. There can be additional sub-level domains with virtually no limitation. Below these levels, the most right domain name component is used to designate a particular host server, for example www for a world wide web server, ftp for an FTP server, or any other label. A domain name with TLD, SLD and hostname is called a fully qualified domain name (FQDN), for example

Local domain names used in local networks can be freely chosen by the network administrator, but some TLD’s should be avoided. For example Apple uses the domain extension .local for it’s implementation of zero-configuration networking called Bonjour.

To map domain names to IP addresses, a Domain Name System (DNS) is used.

IP Address

An IP Address (Internet Protocol address) is a numerical label assigned to each device participating in a computer network that uses the Internet Protocol for communication. The designers of the Internet Protocol defined an IP address as a 32-bit number (IPv4) which is still in use today. A new version of IP (IPv6), using 128 bits for the address was developed in 1995 to avoid a depletion of the available addresses. Its deployment has been ongoing since the mid-2000s.

IP addresses are usually written and displayed in human-readable notations, such as (IPv4), and 2001:db8:0:1234:0:567:8:1 (IPv6).

An IP address is logically recognized as consisting of two parts: the network prefix and the host identifier, or interface identifier (IPv6). The routing prefix is expressed in CIDR (Classless Inter-Domain Routing) notation. It is written as the first address of a network, followed by a slash character (/), and ending with the bit-length of the prefix. For example, is the IPV4 prefix starting at the given address, having 24 bits allocated for the network prefix, and the remaining 8 bits reserved for host addressing.

IPv4 reserves some addresses for special purposes such as private (local) networks or multicast addresses. The following ranges are reserved for private networks :

Prefix length Start End

In IPV6, the reserved address blocks for private networks are referred to as unique local addresses (ULA) and they use the routing prefix fc00::/7.

IP addresses can be static (fix) or dynamic. Static IP addresses are manually assigned to a computer by the network administrator. Dynamic IP addresses are assigned either by a server (router) using Dynamic Host Configuration Protocol (DHCP) or by the computer itself, as in Zeroconf. In the last case of address autoconfiguration (link-local address) the address block is reserved in IPv4 networks and the block fe80::/10 in IPV6 networks.


In IPV4 a subnet mask is used to indicate how the IP address is divided into network and host parts. A subnet mask is made by setting network bits to all “1”s and setting host bits to all “0”s. For example, is the network mask for the prefix.


Routing is the process of selecting best paths in a network. Routing schemes differ in their delivery semantics:

  • unicast : destination is a single specific node in the network
  • broadcast : destinations are all nodes in the network
  • multicast : destinations are all interested nodes in the network
  • anycast : one to many routing topology
  • geocast : destinations are all nodes in a geographical area

Unicast is the dominant form of message delivery on the Internet.

DNS Resolver

The main job of a DNS server is to store DNS name data and serve it when it receives requests. The main job of a DNS resolver is to transform a DNS name into an IP address, but this is only one of several types of resolution services performed by DNS. The process to resolve an hostname to an ip address is normally called dns lookup.

Reverse DNS lookup or reverse DNS resolution (rDNS) is the determination of a domain name that is associated with a given IP address.

Accessing local virtual hosts

There are different ways that local websites can be viewed from other computers which are connected within the same LAN. These computers can be desktops or laptops running Windows, Mac OSX, Linux or be mobile devices like tablets (iPad, Samsung, …) or smart phones (iPhone, Android, …).

  • Use the LAN IP of the server : downside – only one website can be accessed
  • Use the LAN host name of the server : downside – only one website can be accessed
  • Use a LAN-wide hosts file : downside – this doesn’t work on iOS and most other mobile devices
  • Use own DNS server : downside – setup is complex ; DNS server must always be turned on
  • Use a Wi-Fi router with DNS Masquerading : downside – only a few routers support this option
  • Use registered domain names : downside – all website domain names must have a common base; works only with Internet access
  • Use a HTTP proxy server : downside – multiple

We are analyzing now what solution to adapt for a real network case, related to the specific RadioLogic project.

RadioLogic project requirements

RadioLogic is an university education tool for radiologists which uses three websites, working as virtual hosts :

  • : hosted on Amazon AWS, this website provides the tools and data for public users
  • : hosted on a local server, this website provides the tools and data for private users on a local network
  • : hosted on a local server, this website provides the beta versions of new tools and data for testing before deployment on the public and private hosts

If possible, the IT consumerization policy BYOD (Bring your own device) is promoted allowing the radiologists in residence to use their own devices. The local server is a MacBookAir laptop running OSX Yosemite 10.10.5 or later. The clients are iPads running iOS 8.1.4 or later. Both the server and the clients will be used for other purposes.

There exist four operational modes :

  1. The server is used as standalone client without Internet connection
  2. The server is used as standalone client with an Internet connection through a Wi-Fi router
  3. An iPad is used as client with an Internet connection through the same Wi-Fi router (same local network)
  4. An iPad is used as client with a local AdHoc Wi-Fi Connection (SSID = radiologic-open) established by the server

The following figure shows the four operational modes.


RadioLogic : four operational modes

The project requirement is that the same host names are used in each operation mode to access the three websites. Let’s examine how to achieve this goal.

Server without Internet connection used as a client

Without Internet connection, it’s not possible to access the public website To access the local websites and, the most simple solution is to use the internal hosts file available on every desktop computer (Windows, Linux, Mac OSX, …). This configuration file for the loopback interface is located at /private/etc/hosts on the Mac OSX, but it’s also accessible through the more traditional location /etc/hosts. This file is configured as follows :

# Host Database
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##	localhost	broadcasthost
::1             localhost

The default values are the IP addresses for the localhost in IPV4 and IPV6 and the broadcasthost for IPV4. The radiologic hosts have been added.

Server with Internet connection used as a client

Accessing the public website is now possible and the preceding loopback solution is also working.

iPad used as a client with Internet connection in local network

There is no problem to access the public website, but the simple loopback solution to access the local hosts is not possible on mobile devices without jailbreaking.

The next possibility consists in using a local DNS server. Setting up a DNS server on the Mac laptop with primary zones for the local hosts needs a parameter change in the DNS configuration of the iPad Wi-Fi connection.


Wi-Fi settings in iPad

We must change the IP address of the DNS server, assigned by the Internet provider via the Wi-Fi router, by the local IP address of the Mac laptop, which leads to various problems :

  • The IP address of the Mac laptop changes when you use it in a different local network or when the DHCP server assigns a new address in the same network at booting
  • The DNS server of the Mac laptop must be continuously running to use the iPad for Internet surfing
  • Using an additional DNS server with forwarding to a public DNS server to set up an Internet connection may lead to delays or performance problems
  • Frequent changes of the DNS addresses on an iPad is an error-prone process for a normal user

I recommend to never change the network parameters assigned by the Internet provider on your router and local devices to avoid all sort of problems.

There exist a third solution to access the local hosts in our case, which some developers consider as a hack : using the public DNS server to point towards the internal private IP address of the Mac computer.

This solution is simple and feasible in our case because all hosts use the same domain name which is registered and managed in a public DNS server. Instead of creating an A record for both and we can use a wild-card (*) to catch all DNS records.

Some reasons to not use a public DNS server with local IP addresses, invoked by other developers, are the following :

  • leak of internal informations to third parties
  • it’s not considered best practice
  • external clients may inadvertently be redirected to a host on their own local network
  • it’s likely to cause confusion and human miscommunication
  • risk of mail delivery timeouts or mail bounces
  • risk of DNS rebinding attacks

I don’t agree with these arguments that I consider as minor problems or not applicable in specific cases. I think the solution is not a such bad idea in practice and I will use it in the RadioLogic project.

Some routers provide a security feature to protect against DNS rebinding attacks by suppressing DNS responses that refer to IP addresses in the home network. My router FRITZ!Box 7390 is such a device. It allows to enter domain names in a list of exceptions where this protection should be disabled. In our case these are and


Exceptions to the DNS rebinding protection in the Fritz!Box router 7390

iPad used as a client connected to an AdHoc network

The only workable solution in this case is the use of a local private DNS server. You may ask what about the problems listed in the preceding chapter ? Well, these are no longer issues in the case of an AdHoc Wi-Fi network :

  • The self-assigned IP address of the AdHoc Wi-Fi interface in the range can be defined as static
  • The DNS server is always running when the Mac laptop runs the AdHoc network
  • Without Internet connection there is no forwarding to a public DNS server
  • The DNS address is changed once in the configuration of the AdHoc Wi-Fi connection which is different from the configuration of the other Wi-Fi infrastructure connections

Search Domain

In iOS and OSX Wi-fi settings, each Wi-fi connection has a Search Domains section which is simply a convenience that allows the system to convert host names to Fully Qualified Domain Names (FQDN). Anyplace you might use a FQDN, such as in the location bar of Safari,  you can use a simple host name. If the system can’t resolve that host name to an IP address, then it will try appending the search domain to the host name and try again. If you specified more than one search domain, it will try them each in order.

If we set the search domain to, we can use the host names dev and local to access the corresponding websites. I didn’t opt for this solution because it introduces more complexity and an additional delay in setting up connections.

Network Diagnose Tools

There are several tools available for iPads to diagnose access problems in local networks:


iPad Network Analyzer : ping statistics – LAN overview


The following list provides links to websites with additional informations about accessing local virtual hosts :

Mac OSX Wireless Networks

Last update : September 17, 2015

AdHoc Wi-Fi Networks

Sometimes it’s useful to create a WLAN (wireless network) between two or more Wi-Fi-enabled computers without using an Wi-Fi router. These computer-to-computer networks are usually referred to as AdHoc wireless networks.


Create an ad-hoc Wi-Fi network on Mac OSX

On a Mac OSX (Yosemite 10.10.5) it’s easy to set up such a network. Choose Create Network from the Wi-Fi status icon in the menu bar. Enter a name (in my case : radiologic-open) for the new network and select the channel (default channel = 11). You will notice that there is no password protection to secure the network. A WEP (Wired Equivalent Encryption) algorithm was however available in previous versions of the OSX system. WEP was Wi-Fi’s first encryption standard and was almost intentionally designed to be weak due to issues related to the US export policies about encryption. WEP was deprecated in 2003 and replaced by WPA2 (Wi-Fi Protected Access) by the Wi-Fi Alliance.

In Yosemite, Apple killed WEP once for all, without replacing it by another protection method in AdHoc mode.


Chose name and channel for the AdHoc network

If the icon isn’t in the menu bar, choose Apple menu > System Preferences, then click Network (réseau). Click Wi-Fi and select the Show Wi-Fi status in menu bar checkbox.


Mac OSX System Preferences

The Wi-Fi status menu shows the established connection with the radiologic-open network. The menu allows an easy logout and reconnection to another Wi-Fi network. An automatic logout occurs when the Mac screen is powered off.


Wi-Fi status menu shows the AdHoc network active

Infrastructure Wi-Fi networks

There exist a second possibility to set up a Wi-Fi network on Mac OSX. The computer is configured as a software Wi-Fi base station. This allows to share an Internet connection and offers a password protection, but it has another inconvenience. You need a working wired Ethernet connection between your Mac and a hub, even if the hub is not connected to the Internet. The next picture shows my test setup: my MacBookAir is connected via a Ethernet-Thunderbolt interface to an ancient 10 Mbit/s Ethernet hub.


MacBookAir connected with Thunderbolt-Ethernet interface to hub

First you need to configure the Ethernet-Thunderbold interface. Go to Network in System Preferences and select the automatic configuration. The interface gets a self-assigned IP address in the range 169.254.x.x.


Ethernet-Thunderbolt automatic configuration

In the next step go to the Sharing Preference Pane in the System Preferences. Select Ethernet-Thunderbold as source port and Wi-Fi as destination port. Select Wi-Fi options to enter a name (in my case : radiologic-secure) of the network, to select a channel and to define a password (minimum 8 characters; numbers are not recognized on BlackBerry and Android).

Internet Sharing Wi-Fi network configuration

Internet Sharing Wi-Fi network configuration

Finally check the Internet sharing checkbox and confirm the settings to activate the connection.


Activate the Internet sharing

The resulting pane is shown below.


Activated Internet sharing pane

The Wi-Fi status is updated automatically. To log out, desactivate the Wi-Fi connection in the corresponding menu. An automatic logout occurs when the Mac screen is powered off.


Wi-Fi status menu showing Internet sharing

The following table shows which of my devices are capable to connect to the Mac OSX AdHoc and Infrastructure networks.

Device Wi-Fi AdHoc Wi-Fi infrastructure
iPad OK OK
iPhone OK OK
BlackBerry  network not shown network joined, but
no access to host
Samsung Tablet (Android 4.2.2) network not in range network joined, but
no access to host
Laptop Vista no connection network joined, but
no access to host
Desktop Windows 8.1 network not shown OK
Laptop Debian no connection OK

Wi-Fi Diagnostic

To detect the reasons why some devices don’t connect to the Mac OSX Wi-Fi AdHoc or Infrastructure networks, you can use a WLAN analyser. Mac OS X Yosemite has an in-built Wi-Fi scanner to help you find the best Wi-Fi channel. When you hold down the option key ⌥ (next to the CTRL key) and select the Wi-Fi icon in the menu bar, a secret dropdown menu opens.


Secret Wi-Fi dropdown menu in Mac OSX Yosemite

Open Wireless Diagnostics and click it. After you have gotten to the page and have opened up the Wireless Diagnostics window, go to the top left of your menu bar and click on Window where you find several options: Informations, history, scan, performance, detection, …  Some results are shown below.

Mac OSX Wi-Fi Analyser

Mac OSX Wi-Fi Analyser

Another WLAN tool is available on Windows computers. When you enter the command

netsh wlan show networks mode=bssid

in the command window, you will get the following results :


Microsoft Wi-Fi Analyser

A third WLAN tool is integrated in my Wi-Fi router FritzBox 7390. Various wireless networks in my neighborhood are shown, but nor the channels used by the Mac OSX nor the names of these networks are listed. I don’t know why ?


Wi-Fi channels used in proximity of the Fritzbox

There are also several external software tools for Wi-Fi-analysis available, for example Acrylic Wi-Fi Free or Acrylic Wi-Fi Professional. The main window (Access points,  Signal strength) of Acrylic is shown hereafter :

Acrlylic Wi-Fi Analyser

Acrlylic Wi-Fi Analyser

Some additional windows (stations, packet viewer, 2,4 GHz APs channels, detailed info) are shown below :

Various Acrylic results

Various Acrylic results

Wi-Fi Assessment

Several methodologies are available dealing with safety aspects of wireless networks, for example :


The following list shows links to websites providing additional informations about Wi-Fi networks, related to Mac OSX.

Volunteer Computing

Volunteer computing is an arrangement in which people (volunteers) provide computing resources to projects which use the resources to do distributed computing and/or storage. Distributed computing is a field of computer science that studies distributed systems. A distributed system is a software system in which components, located on networked computers, communicate and coordinate their actions by passing messages.

Neural networks are very good candidates for simulation by distributed computing systems because of their inherent parallelism and beacuse its simulation is a very time consuming process, due to the complex iterative process involved.

The first volunteer computing project was the Great Internet Mersenne Prime Search, which was started in January 1996. The term volunteer computing was coined by Luis F. G. Sarmenta, the developer of Bayanihan.

The Berkeley Open Infrastructure for Network Computing (BOINC) is the most widely-used middleware system for volunteer computing. It offers client software for Windows, Mac OS X, Linux, and other Unix variants. The project was founded at the University of California, Berkeley Space Sciences Laboratory, funded by the National Science Foundation. Other systems are XtremWebXgrid and Grid MP.

Volunteer computing systems must deal with the following problems, related to correctness :

  • Volunteers are unaccountable and essentially anonymous
  • Some volunteer computers occasionally malfunction and return incorrect results
  • Some volunteers intentionally return incorrect results or claim excessive credit for results

A list of distributed computing projects is provided at Wikipedia. Links to a few selected BOINC volunteer computing projects are listed below :


oEmbed is a format for allowing an embedded representation of a URL on third party sites. The simple API allows a website to display embedded content (such as photos or videos) when a user posts a link to that resource, without having to parse the resource directly.

An oEmbed exchange occurs between a consumer and a provider. A consumer wishes to show an embedded representation of a third party resource on their own web site, such as a photo or an embedded video. A provider implements the oEmbed API to allow consumers to fetch that representation. The response returned by the provider can be in either JSON or XML.

The following types are defined :

  • photo
  • video
  • link
  • rich

The authors of oEmbed are Cal Henderson, Mike Malone, Leah Culver and Richard Crowley. Among the providers of oEmbed are Youtube, Flickr, Vimeo, WordPress and Slideshare.

UPnP Technology and Test Tools

Universal Plug and Play (UPnP) is a set of networking protocols that permits networked devices, such as personal computers, printers, gateways, servers and mobile devices to seamlessly discover each other’s presence on the network and establish functional network services for data sharing, communications, and entertainment. UPnP is intended primarily for residential networks. No special device driver support is necessary, common network protocols are used (TCP/IP, HTTP, XML, SOAP). UPnP uses UDP port 1900 and TCP port 2869.

The UPnP technology is promoted by the UPnP Forum. Formed in October 1999, the UPnP Forum is an industry initiative of more than 1000 leading companies in computing, printing, networking, consumer electronics and home appliances. A huge library of UPnP resources is available at the website of the UPnP Forum.

UPnP was published as an international standard, ISO/IEC 29341, in December 2008.

The foundation for UPnP networking is IP addressing, either by DHCP or by AutoIP (zero configuration networking). The next step in UPnP networking is discovery, based on the Simple Service Discovery Protocol (SSDP). SSDP allows a device to advertise its services to control points, for example to media servers (Serviio) on the network. The next step is to learn more about the discovered device and its capabilities by retrieving the device’s XML description from the URL provided by the device in the discovery message. Now the control point can send actions to a device’s service using the Simple Object Access Protocol (SOAP).

An additional capability of UPnP networking is event notification, or eventing. The event notification protocol defined in the UPnP Device Architecture is known as General Event Notification Architecture (GENA). The final step in UPnP networking is presentation, usually by providing an URL of a webpage loaded in a browser.

UPnP AV is an audio and video extension of UPnP, referenced in specifications published by other organizations, including the Digital Living Network Alliance (DLNA).

Problems with UPnP are lack of authentication and vulnerabilities with the risk that UPnP devices can be accessed and/or manipulated by malicious web sites.

A complete set of open source tools for creating and testing UPnP solutions is provided by Intel. They include Device Spy, a generic control point, and Device Builder, a code generation tool. In all, there are 11 tools in this package that range from low-level debugging to full reference tools :

  • Device Spy
  • Device Sniffer
  • Network Light
  • Device Builder
  • Device Relay
  • Device Validator
  • Service Author
  • AV Media Controller
  • AV Media Server
  • AV Media Renderer
  • AV Wizard

Network Light is a software model of an UPnP device to show the basic functions of the UPnP protocol. The light can be switched on/off or dimmed. The following snaps show how


UPnP Network Light OFF / ON / DIMMED

UPnP Device Spy Tool

UPnP Device Spy Tool


UPnP Device Spy Tool : Invoke action DIM 50%

UPnP Device Spy Tool : Invoke action ON

UPnP Device Spy Tool : Invoke action ON

UPnP Device Sniffer Tool

UPnP Device Sniffer Tool

Another UPnP test tool, called UPnP Inspector, has been developed by Coherence. The Inspector is an UPnP Device and Service analyzer, and a debugging tool, based on the Coherence DLNA/UPnP framework. It is loosely modeled after the Intel UPnP Device Spy and Device Validator.

UPnP Inspector

UPnP Inspector

UPnP Inspector logs

UPnP Inspector logs

UPnP Inspector action

UPnP Inspector action

UPnP Inspector details

UPnP Inspector details



Last update : September 11, 2013

A Direct-attached storage (DAS) is a file-level computer data storage system directly attached to a server or workstation, without a storage network in between. The main protocols used for DAS connections are ATA, SATA, eSATA, SCSI, SAS, and Fibre Channel.

A storage area network (SAN) is a dedicated network that provides access to consolidated, block level data storage. A SAN does not provide file abstraction, only block-level operations.

A Redundant array of independent disks (RAID) is a storage technology that combines multiple disk drive components into a logical unit. Data is distributed across the drives in one of several ways called RAID levels, depending on what level of redundancy and what performance is required. In RAID 1, data is written identically to two drives, thereby producing a mirrored set.

A Network-attached storage (NAS) is a file-level computer data storage system connected to a computer network, providing data access to a heterogeneous group of clients. A NAS, in contrast to a SAN, uses file-based network sharing protocols such as NFS, SMB, CIFS or AFP. NAS systems are networked appliances which contain one or more hard drives, often arranged into logical, redundant storage containers or RAID arrays. The benefits of network-attached storage, compared to file servers, include faster data access, easier administration, and simple configuration.

The storage space can be comprised of USB or hard disk drives. A NAS can be sold with the drives included or without them. Like PCs, NAS units have memory and processors. With better processors and increased memory, you get better performance from a NAS, just as with PCs. Lunix is usually used as embedded operating system. Noise and security are two other important concerns.

In the last years, NAS devices have been gaining popularity in the home office (SOHO), because they are useful for more than just general centralized storage provided to client computers in environments with large amounts of data. Typical other usages are :

  • load balancing
  • email server
  • web server
  • media server
  • multimedia streaming
  • cloud-based backup
  • low-cost video surveillance
  • BitTorrent client

A list of NAS manufacturers is provided at Wikipedia. A list of links to additional informations about SAN’s is provided below :

DLNA Media Servers and Players

Last update : March 12, 2013

The following list provides links to informations about DLNA media devices, especially Media Servers :

A list of additional media servers and client applications is available on Wikipedia which provides also a comparisons of UPnP AV media servers.

Apple developed its own proprietary streaming protocol stack/suite, called AirPlay, that is not compliant with DLNA. Another solution to stream multimedia files is based on the SMB/CIFS networking protocols, re-implementated with Samba to open windows to a wider world.

I recommend the Serviio DLNA server which I installed a week ago on my two Windows 7 desktops to replace Windows Media Players.

Windows Media Player DLNA Configuration

Last update : June 17, 2012
A personal computer running Windows XP, Windows Vista or Windows 7 can be used as a DLNA certified media server simply by activating this capability in the Windows Media Player (WMP) 11 or above. Some tutorials how to configure the WMP are listed hereafter :

In the past the media server components, now integrated in the WMP, were called Windows Media Connect (WMV) or Home Media Ecosystem (HME). The Windows Media Center (WMC) includes a digital video recorder.

Late April 2012 I set up a DLNA system in my home network with a Fritz!Box Media Server and two Windows Media Players 12 running on Windows 7 personal computers.

Six weeks later I replaced the Windows Media Player system by the outstanding Serviio DLNA server. I disabled the Windows 7 Media Player Network Sharing Service (wmpnetwk) to avoid conflicts in media sharing and to speed up the system’s perfomance. A tutorial how to turn off wmpnetwk.exe is available on numerous websites.