Network Address Translation (NAT) presents significant challenges for battery-powered IoT devices aiming for low power consumption. Because devices behind NAT can't be directly addressed from the outside, they must maintain persistent outbound connections to receive data, negating the power-saving benefits of sleep modes. Techniques like keep-alive messages or frequent polling to maintain these connections consume significant energy. This post advocates for solutions that bypass NAT, such as IPv6 with its vast address space enabling globally routable unique addresses for each device, or by employing intermediaries like a message broker positioned outside the NAT. These approaches allow devices to initiate communication only when necessary, drastically reducing power consumption and extending battery life.
Enterprises adopting AI face significant, often underestimated, power and cooling challenges. Training and running large language models (LLMs) requires substantial energy consumption, impacting data center infrastructure. This surge in demand necessitates upgrades to power distribution, cooling systems, and even physical space, potentially catching unprepared organizations off guard and leading to costly retrofits or performance limitations. The article highlights the increasing power density of AI hardware and the strain it puts on existing facilities, emphasizing the need for careful planning and investment in infrastructure to support AI initiatives effectively.
HN commenters generally agree that the article's power consumption estimates for AI are realistic, and many express concern about the increasing energy demands of large language models (LLMs). Some point out the hidden costs of cooling, which often surpasses the power draw of the hardware itself. Several discuss the potential for optimization, including more efficient hardware and algorithms, as well as right-sizing models to specific tasks. Others note the irony of AI being used for energy efficiency while simultaneously driving up consumption, and some speculate about the long-term implications for sustainability and the electrical grid. A few commenters are skeptical, suggesting the article overstates the problem or that the market will adapt.
Summary of Comments ( 83 )
https://news.ycombinator.com/item?id=43003999
Several commenters on Hacker News discussed the challenges of NAT traversal for low-power devices, agreeing with the article's premise. Some suggested solutions like using a TURN server or a lightweight VPN, while others pointed out the benefits of IPv6 in eliminating the need for NAT entirely. One commenter highlighted the trade-offs between power consumption and complexity when implementing these workarounds, and another mentioned the difficulty of managing NAT keepalives with devices that sleep frequently. The issue of scaling these solutions for a large number of devices was also raised. Several users shared personal anecdotes of struggling with similar NAT issues. One commenter proposed a simpler approach involving a central server that all devices could communicate with, bypassing direct peer-to-peer communication and thus avoiding NAT complications altogether.
The Hacker News post "NAT Is the Enemy of Low Power Devices" generated several comments discussing the challenges of Network Address Translation (NAT) for low-power, battery-operated IoT devices.
Several commenters agreed with the article's premise. One highlighted the inherent difficulty in establishing inbound connections to devices behind NAT, emphasizing the power consumption overhead associated with maintaining persistent connections or using techniques like keep-alives. They also mentioned the complexities introduced by Carrier-grade NAT (CGNAT), where multiple layers of NAT further complicate inbound connections.
Another commenter pointed out the security implications of opening ports on a home router for these devices, suggesting that it exposes the entire local network to potential vulnerabilities. They advocated for cloud-based solutions like the one offered by Golioth (the article's author), where devices initiate outbound connections to a central server, eliminating the need for inbound port forwarding.
The discussion also touched upon alternative approaches to circumvent NAT limitations. One commenter suggested using protocols designed for peer-to-peer communication, like WebRTC, which can establish connections even behind NAT. However, another commenter countered that WebRTC still requires a signaling server and might not be suitable for all low-power applications due to its relatively high overhead.
Some commenters questioned the framing of NAT as the "enemy." They argued that NAT is a crucial part of the current internet infrastructure and that the real challenge lies in developing efficient protocols and architectures for IoT devices that can work within the constraints of NAT. They proposed solutions like using UDP hole punching or having devices establish outgoing connections to a central server.
One commenter explored the specific challenges posed by CGNAT, noting the scarcity of IPv4 addresses and the consequent widespread deployment of CGNAT by internet service providers. They mentioned techniques like STUN (Session Traversal Utilities for NAT) and TURN (Traversal Using Relays around NAT) but acknowledged their limitations and complexity, particularly for low-power devices.
Finally, a few commenters mentioned specific technologies and protocols, like MQTT and CoAP, which are commonly used in IoT and are designed to be efficient in low-power and bandwidth-constrained environments. They discussed how these protocols can be used in conjunction with cloud-based services to overcome the challenges posed by NAT.