Building smart devices…some initial guidelines…

Wandering back to CPS/IoT stuff for awhile. First off today I am thinking about what is connected. I have previously talked about the many points of integration. Today I want to talk about the many devices you potentially will be connecting your device with.

Connections can be cellular, Bluetooth, Wi-Fi or Near Field communication and even packet radio. You could if you wanted even use Ethernet or traditional POTs lines for connections. All of these connecting to a single device. That device then consuming the various services and translating those into something you can act on.

The types of available connections are critical. The value of a connection is the distance and the amount of data it can handle. Bluetooth is good for short bursts and close range devices. Wi-Fi is good for moving larger amounts of data over a slightly greater distance. Cellular allows for voice and video transmission anywhere in the world. Ethernet remains best for moving massive amounts of data reliably anywhere in the world.

This brings to the initial question of connection for devices. What are you transmitting. Where will it end up? And, perhaps most scary of all, How much data is it?

What you are transmitting changes and evolves. When I first got a computer one of the things I did was buy hardware to connect my piano to the computer via MIDI. Now, I can use wireless MIDI connections. Originally I had a single device (Macintosh IIci) connected to my keyboard. Now, using PUC I can connect my keyboard to any device eon my house.

Where does it end up then changed. Now I can connect my keyboard to my iPad, iPhone and my computer. Notes played on the keyboard can be presented directly on the computer screen as notes annotated as music. So where it ends up has changed radically.

In 1991 I had a single POTs connection to the internet. Roughly 56kb or less was the overall maximum speed available. One computer connected at a time.

In 1996 I got an ISDN line to the house. That 64 KB line allow me to have more than 3 computers connected. But, it was limited. In 1999 I upgraded to 128kb ISDN. I still was limited but bandwidth was improving!

Things, that back in the 90’s we dreamed about are routine now. In the 90’s if you wanted to watch a movie you went to a video store and hoped they weren’t out of good movies. Now you watch it live on Netflix, Hulu or Amazon Instant Video. It does however bring up the last reality of IoT and CPS going forward.

I worked with a really smart network engineer many years ago. He used to say it isn’t how much data you want to move. Its how much data everyone else wants to move at the same time. The concept of intelligent divides that are aware of the confines of the network they are on is the future. How much data do I need to move, should take into account the following limitations.

  • The bandwidth available for transmission from where the device is currently.
  • The bandwidth I have available for consumption of the information that is being sent.
  • The capabilities of the device I am currently using for the consumption (screen, memory and processor)
  • The nature of the information. (i.e., if it is sensitive information remove it from the device right after it is consumed).
  • The last one – data retention or governance requirements beyond the security of the actual information.

What I am sending. Where I am sending it to and how much data I am sending is something devices have to begin understanding.


yes I am talking bandwidth again….