Stories with Tag MNOS

• The Miserable State of Modems and Mobile Network Operators

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  Posted: 2025-02-26 11:55:26

  Verbose tl;dr

  The blog post "The Miserable State of Modems and Mobile Network Operators" laments the frustrating developer experience of integrating cellular modems into IoT projects. It criticizes the opaque and inconsistent AT command interfaces, the difficult debugging process due to limited visibility into modem operations, and the complex and often expensive cellular data plans offered by MNOs. The author highlights the lack of standardized, developer-friendly tools and documentation, which forces developers to wrestle with legacy technologies and proprietary solutions, ultimately slowing down IoT development and hindering innovation. They argue for a simplified and more accessible ecosystem that empowers developers to leverage cellular connectivity more effectively.

  The blog post "The Miserable State of Modems and Mobile Network Operators," published on Golioth's website, delivers a scathing critique of the current landscape of cellular modem integration for Internet of Things (IoT) applications. The author meticulously outlines the numerous frustrations and complexities encountered when attempting to establish reliable and efficient cellular connectivity for IoT devices, placing the blame squarely on both modem manufacturers and Mobile Network Operators (MNOs).

  The central argument revolves around the inherent difficulty in navigating the fragmented ecosystem surrounding cellular modems. The author argues that the process, from selecting a suitable modem to successfully deploying it in the field, is riddled with opaque documentation, inconsistent implementations of standards, and a general lack of user-friendliness. Specifically, the blog post criticizes the convoluted AT command set, highlighting its historical baggage and the inconsistencies between different modem models, even those from the same manufacturer. This lack of standardization forces developers to write bespoke code for each modem, thereby hindering scalability and increasing development time and costs.

  Furthermore, the post laments the inadequate documentation provided by modem manufacturers. The author contends that the available documentation is frequently incomplete, outdated, or simply inaccurate, making it a significant hurdle for developers seeking to understand the nuances of a particular modem's behavior. This opacity extends to the realm of firmware updates, which are often shrouded in mystery and difficult to apply, potentially leading to unresolved bugs and security vulnerabilities.

  The criticism extends beyond modem manufacturers to encompass Mobile Network Operators (MNOs) as well. The author points to the often arbitrary and obscure restrictions imposed by MNOs regarding data usage, SIM card activation, and network access. These limitations, combined with the complexities of negotiating data plans and managing SIM card lifecycles, further complicate the already challenging process of deploying cellular-connected IoT devices. The author specifically highlights the difficulties in obtaining and maintaining static IP addresses, a crucial requirement for many IoT applications.

  The blog post also touches upon the issue of security, expressing concerns about the potential vulnerabilities inherent in cellular modems. The lack of transparency and the difficulty in applying firmware updates exacerbate these security concerns, leaving IoT devices potentially exposed to malicious actors.

  In conclusion, the author paints a bleak picture of the current state of cellular modem integration for IoT applications. The fragmented ecosystem, coupled with inadequate documentation, inconsistent implementations, and arbitrary restrictions imposed by MNOs, creates a significant barrier to entry for developers seeking to leverage the power of cellular connectivity. The post implicitly calls for greater standardization, improved documentation, and more transparent practices from both modem manufacturers and MNOs to facilitate the wider adoption and successful deployment of cellular-connected IoT devices.

  • modems
  • mobile networks
  • cellular networks
  • MNOS
  • mobile network operators
  • IoT
  • Internet of Things
  • connectivity
  • telecom
  • Telecommunications
  • Wireless
  • Cellular IoT
  • SIM cards
  • eSIM
  • iSIM

  Summary of Comments ( 0 )
  https://news.ycombinator.com/item?id=43182854

  Verbose tl;dr

  Hacker News commenters largely echoed the author's frustrations with cellular modem integration. Several shared anecdotes of flaky connectivity, opaque documentation, and vendor lock-in issues, particularly with Quectel and SIMCom modems. Some pointed to the lack of proper abstraction layers as a core problem, hindering software portability. The difficulty in obtaining certifications for cellular devices was also highlighted, with some suggesting this complexity benefits larger established players while stifling smaller innovators. A few commenters suggested exploring alternatives like the Nordic Semiconductor nRF91 series or using a Raspberry Pi with a USB cellular dongle for simpler prototyping, while others called for more open-source initiatives in the cellular modem space. Several also discussed the challenges with varying cellular carrier regulations and certification processes internationally. The general sentiment was one of agreement with the article's premise, with many expressing hope for improved developer experience in the future.

  The Hacker News post "The Miserable State of Modems and Mobile Network Operators" generated a moderate amount of discussion, with several commenters sharing their own experiences and perspectives on the challenges of working with cellular modems and mobile network operators (MNOs).

  Several comments echoed the author's frustrations with the opaque and complex nature of cellular technology. One commenter lamented the difficulty in finding clear documentation and the lack of standardization across different modems and networks. This sentiment was reinforced by another who described the process of integrating cellular connectivity as a "nightmare," citing inconsistent APIs and the need for extensive trial and error.

  The issue of vendor lock-in was also raised, with commenters expressing concerns about being tied to specific modem manufacturers and MNOs. This was particularly problematic for those working on IoT projects, where flexibility and interoperability are crucial.

  A few comments offered alternative perspectives. One commenter suggested that the complexity of cellular technology is inherent due to the stringent requirements of reliability and security in a wireless environment. Another pointed out the significant improvements in cellular technology over the past few years, particularly with the advent of newer standards like LTE-M and NB-IoT, suggesting the author's experience might be specific to older technologies or particular vendors.

  There was some discussion around the challenges of managing SIM cards and data plans for large deployments of IoT devices. Commenters mentioned difficulties with provisioning SIM cards, managing data usage, and dealing with varying roaming agreements across different countries.

  Some practical suggestions were also offered. One commenter recommended using virtual SIMs (eSIMs) to simplify the process of managing connectivity for IoT devices. Another suggested working with specialized connectivity providers that offer a more streamlined and developer-friendly experience.

  Finally, a few comments touched upon the broader issue of the telecommunications industry's structure and its impact on innovation. One commenter argued that the lack of competition among MNOs has stifled innovation and led to higher prices and poorer service for consumers.

  While the comments largely agreed with the author's premise about the difficulties of working with modems and MNOs, they also provided a nuanced view, acknowledging the complexities of cellular technology and offering some practical solutions and alternative perspectives. The discussion highlighted the need for greater transparency, standardization, and developer-friendliness in the cellular connectivity space, especially as the demand for IoT devices continues to grow.

• The bucket brigade device: An analog shift register

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  Posted: 2024-11-15 13:27:08

  Verbose tl;dr

  The Bucket Brigade Device (BBD) is an analog shift register implemented using a chain of capacitors and transistors. It stores analog signals as charge packets on these capacitors, sequentially transferring them along the chain with the help of a clock signal. This creates a time delay proportional to the number of stages in the brigade. BBDs were historically used for audio effects like delay, chorus, and reverberation because of their simplicity and relatively low cost. However, they suffer from signal degradation due to charge leakage and require careful biasing and clocking for optimal performance. Despite being largely superseded by digital technologies, BBDs offer a fascinating example of analog signal processing.

  The blog post "The bucket brigade device: An analog shift register" explores the fascinating functionality and historical significance of the bucket brigade device (BBD), an analog circuit capable of delaying analog signals. The author meticulously explains how this ingenious device operates by analogy to a line of firefighters passing buckets of water along a chain. Just as each firefighter receives a bucket from one neighbor and passes it to another, the BBD transfers packets of charge between adjacent capacitors. This transfer, controlled by a clock signal, effectively moves the analog signal down the chain of capacitors, creating a delay proportional to the number of stages and the clock frequency.

  The post delves into the underlying physics, describing how MOS transistors, acting as switches, facilitate the transfer of charge packets. It emphasizes the importance of the clock signal in coordinating this transfer and preventing the signal from degrading. The bidirectional nature of the charge transfer, allowing for both forward and reverse movement of the signal, is also highlighted. The author further elaborates on the advantages of using MOS capacitors for charge storage, emphasizing their small size and compatibility with integrated circuit technology.

  The post then explores the practical applications of BBDs, particularly their historical role in early electronic music synthesizers and other audio effects. By varying the clock frequency, the delay time can be modulated, creating effects like vibrato, chorus, and phasing. This dynamic control over the delay was crucial for achieving specific musical nuances and textures in these early electronic instruments. The author illustrates this point with examples and explanations of how these effects are achieved.

  Finally, the post touches upon the limitations of BBDs, including noise introduced during the charge transfer process and the eventual decay of the signal due to leakage currents. These imperfections, while inherent in the analog nature of the device, contribute to the characteristic "warmth" often associated with analog audio effects. Despite these limitations and their eventual replacement by digital technologies, the BBD remains a testament to ingenious analog circuit design and its impact on the development of electronic music. The author's detailed explanation and accompanying diagrams provide a comprehensive understanding of the BBD's operation and significance.

  • bucket brigade device
  • analog shift register
  • charge transfer device
  • CCD
  • analog delay line
  • analog signal processing
  • Electronics
  • integrated circuit
  • semiconductor device
  • MNOS
  • MOSFET
  • analog circuits
  • shift register
  • BBD
  • analog delay
  • Signal Processing
  • metal–nitride–oxide–semiconductor
  • MNOS transistor
  • metal-nitride-oxide-semiconductor

  Summary of Comments ( 29 )
  https://news.ycombinator.com/item?id=42146718

  Verbose tl;dr

  HN users generally found the bucket brigade device fascinating. Several commenters discussed practical applications like its use in early audio delay lines and the challenges of clocking it consistently. Others appreciated the clear explanation and visualization of the device's operation, highlighting its simplicity and elegance. Some compared it to charge-coupled devices (CCDs) and discussed their similarities and differences in functionality and implementation. The practicality of using actual buckets filled with water was also debated, with some suggesting the analogy, while visually appealing, might not accurately represent the underlying physics of the electronic device. A few users linked to relevant Wikipedia pages and other resources for further exploration.

  The Hacker News post "The bucket brigade device: An analog shift register" has generated several comments discussing various aspects of the technology.

  Several commenters focused on the practicality and applications of bucket brigade devices (BBDs). One commenter questioned their utility, asking why one would use a BBD instead of just storing samples digitally. This prompted a discussion about the historical context of BBDs, with others pointing out that they predate readily available digital solutions and were used in applications like early synthesizers and guitar effects pedals due to their simplicity and relatively low cost at the time. Another commenter mentioned the use of BBDs in toys and musical greeting cards. This highlighted the BBD's suitability for low-fidelity audio where digital solutions might have been overkill. Someone else mentioned the distinct "analog" sound of BBDs, specifically their characteristic warble and degradation, which became desirable in some musical applications, contributing to their continued niche usage.

  The technical aspects of BBD operation also drew attention. One commenter clarified the functionality, explaining that the charge isn't actually moved across the entire chain of capacitors, but rather small amounts of charge are passed between adjacent capacitors, analogous to a bucket brigade. This clarified the name and underlying principle for other readers. Another comment delved deeper into the physical implementation, describing the use of MOS capacitors and the impact of clock frequency on the delay time.

  One commenter reminisced about experimenting with BBDs and other analog components in their youth. This added a personal touch to the discussion and underscored the historical significance of these devices for hobbyists and early electronics enthusiasts.

  A recurring theme in the comments was the contrast between BBDs and digital delay lines. Commenters explored the trade-offs between the simplicity and unique sound of BBDs versus the fidelity and flexibility of digital approaches. The limitations of BBDs, such as their fixed maximum delay time and susceptibility to noise, were also mentioned. One commenter even discussed the specific challenges of clocking BBDs and the impact of clock imperfections on the output signal.

  Finally, a couple of comments highlighted related technologies, including the use of CCDs (charge-coupled devices) for similar signal processing applications, and drawing parallels with the operation of peristaltic pumps. These broadened the context of the discussion and provided additional avenues for exploration.