What is LPSS Serial Adapter in my network tab

Recently I have found that there are a network device called LPSS Serial Adapter (1) and LPSS Serial Adapter (2) in my network settings on my 2016 15" MacBook Pro, it has a phone (modem I guess) icon:

I tries to delete it, but it just comes back in a reboot. This doe not appear in any other Macs that I've own.

What is it?

P.S. It appears both on macOS Sierra 10.12.1 (16B2659) and 10.12.2 (16C67)

Solution 1:

The LPSS adapters are related to a chip feature on the new 2016 MacBook Pros. I found these interfaces present immediately after setting up a new 15-inch 2016 Touch Bar model out of the box (before plugging in any peripherals or installing any drivers).

The following patent filing for the "low power subsystem" describes an interface through which a "secondary" processor can provide access to the system's memory while the primary processor is powered down:

The subsystem acts independently of the CPU, which would not be able to perform the necessary functions during low power mode. The subsystem allows the notebook to perform several functions while in the low power mode, such as, for example, act like a travel assistant for the user, provide entertainment, and make electronic purchases.