editor's blog
Subscribe Now

Two Kinds of IoT Fog

We’ve heard about the role of the Cloud in the Internet of Things (IoT). It’s analytics and other decision-making that happens in some remote server farm somewhere to serve some “edge-node” device connected over the internet. And you’ve probably heard of the variant on that called the “fog,” where some of that computing is done on a machine local to the edge node, reducing communication traffic and latency.

But… did you know that there are two flavors of fog? And that this actually has an analog in the IoT?

San Francisco is famous as a foggy city, but, unless it’s really bad, the fog doesn’t actually hit the ground. It’s generated by the “marine layer,” coming in off of the cold ocean waters. It’s the West Coast version of the East Coast’s humidity – with no warm Gulf Stream. Newcomers will sometimes look up during a typical San Fran foggy day and wonder, “Why do you call this fog? It’s just cloudy.” (Until you get to a hill or the Outer Richmond, anyway.)

What most people are used to is ground fog (also locally called tule – “too-lee” – fog , named after a prevalent form of bulrush in the local delta from which the fog might seem to arise). Because ground fog originates with moisture on the ground, it never seems simply cloudy. It’s always all the way down; the only question is how high it rises. (And how thick it is…)

So on the one hand, we have a type of fog that might appear to be higher up, with a tendency to descend towards the ground, versus one that starts at the ground and then rises up. This distinction came to me based on a discussion with Olea Sensor Networks during the June Sensors Expo. (They came up in my prior discussion on interoperability.)

They write custom analytics code for IoT devices. In the classic IoT model, such analytics would be performed in the Cloud – with perhaps some offloading into a local machine. This descent of analytics from on high might resemble the San Francisco marine-layer type of fog, where it mostly seems like clouds until it descends.

But Olea noted that they mostly don’t see analytics happening in the Cloud – at least not so far. The analytics they write execute on the edge node devices themselves – and perhaps in other local servers and gateways. But definitely on the local side of things, not the Cloud. So here the fog is rising from the ground up.

Fog_drawing.png 

Of course, as I’ve noted before, we’re in early stages of IoT build-out, with many folks struggling simply to make their phones work as remote controls – never mind the analytics. So this could be a transitory phase. But where you place the analytics has obvious implications for the resources needed on your edge-node device. Which has implications for cost.

What this also suggests is that current analytics functions are relying solely on data from the one device or perhaps from a few local devices that have access to the same server or gateway. Which probably also reflects the youth of the IoT.

At the point when more architects take advantage of data available only through the internet – things like social media feeds, perhaps map feeds, etc. – and work them into the analytics, then the Cloud may be a better place to bring all of that together. Likewise when combining data from edge nodes that are not collocated.

At which point, some tornado will come along and suck it all up into the Cloud.

 

[Editors note: Updated to correct company name from Olea Sensors to Olea Sensor Networks.]

Leave a Reply

featured blogs
Jan 26, 2021
I could doubtless extend this series all year long, covering the important updates, improvements, and completely new functionality that is continually being added to the Allegro ® Package... [[ Click on the title to access the full blog on the Cadence Community site. ]]...
Jan 26, 2021
We just started our next round of gEEk® spEEk online seminars. gEEk spEEk is a series of free online seminars covering a wide-range of SI-related topics, all commercial-free. Stefaan Sercu, Samtec Signal Integrity R&D Engineer, recently presented “Impedance Correc...
Jan 25, 2021
In which we meet the Photomath calculator, which works with photos of your equations, and the MyScript calculator, which allows you to draw equations with your finger....
Jan 20, 2021
Explore how EDA tools & proven IP accelerate the automotive design process and ensure compliance with Automotive Safety Integrity Levels & ISO requirements. The post How EDA Tools and IP Support Automotive Functional Safety Compliance appeared first on From Silicon...

featured paper

Overcoming Signal Integrity Challenges of 112G Connections on PCB

Sponsored by Cadence Design Systems

One big challenge with 112G SerDes is handling signal integrity (SI) issues. By the time the signal winds its way from the transmitter on one chip to packages, across traces on PCBs, through connectors or cables, and arrives at the receiver, the signal is very distorted, making it a challenge to recover the clock and data-bits of the information being transferred. Learn how to handle SI issues and ensure that data is faithfully transmitted with a very low bit error rate (BER).

Click here to download the whitepaper

Featured Chalk Talk

Innovative Hybrid Crowbar Protection for AC Power Lines

Sponsored by Mouser Electronics and Littelfuse

Providing robust AC line protection is a tough engineering challenge. Lightning and other unexpected events can wreak havoc with even the best-engineered power supplies. In this episode of Chalk Talk, Amelia Dalton chats with Pete Pytlik of Littelfuse about innovative SIDACtor semiconductor hybrid crowbar protection for AC power lines, that combine the best of TVS and MOV technologies to deliver superior low clamping voltage for power lines.

More information about Littelfuse SIDACtor + MOV AC Line Protection