How Many Devices Can Your Pie Serve?

The US will celebrate Thanksgiving next week, and that has us thinking about pie. We love pie. And so do devices. In another post we compared a wireless network’s capacity to a pie. And why not, it’s that time of year. The pie analogy helps us properly frame how to measure a wireless IoT network’s performance.

To be clear, a meaningful way to think about capacity is the amount of data that can flow through an AP in an interval of time. Let’s imagine that amount as a pie. The depth of the pie is the time interval, lets say one second. Then the diameter of the pie represents the number of bits that can be transmitted via that technology during that second. So the entire pie represents the AP’s throughput in terms of bits per second, or bps. Pie, oh glorious pie.

We love pie. And so do devices…The pie analogy helps us properly frame how to measure a wireless IoT network’s performance.
Now we’ll put two constraints on the pie that represent the constraints on M2M wireless network technologies. The pie’s size is limited by the technology, in other words, some technologies’ throughput, or bps, are greater than others. The bigger the pie, the more data throughput that technology has. The second constraint is the number of slices each pie can have regardless of the size. In the industry, these slices are called address spaces. And typically these are what companies report when asked what their capacity is. Let’s think for a second why address spaces are kind of a silly way to measure a technology’s performance. If someone says they’ll take care of the pies for a Thanksgiving party, how do you check to make sure you’ll have enough pie? Do you ask them how thinly they can slice the pie pieces? Of course not, you ask about the amount of pie.

There are three scenarios to consider here.

  • Scenario 1: the pie is huge, but can’t be cut into small enough slices to be consumed by the majority of devices. That’s traditional cellular.
  • Scenario 2: the pie is so small that it could never feed the guests (and the growing list of guests, i.e. the projected growth of the IoT), but can be sliced into very small pieces. In other words, you have a super small pie that is sliced into incredibly numerous small slices. This second scenario describes most of the LPWA players, and is also why they tend to use address spaces when talking about capacity; they have lots of slices (but not a lot of pie).
  • Scenario 3: The pie is large and plenteous, and can be sliced into more than enough pieces for all the guests.
Scenario 3 is what Ingenu’s RPMA does. RPMA meets the needs of the devices that need to connect to the IoT. Three cheers for enough pie and slices to go around!

To learn more about how RPMA is able to meet the needs of the majority of IoT devices read our white paper, How RPMA Works.