Re: WWAN Controller Framework (was IPA [PATCH v2 00/17])

From: Alex Elder
Date: Mon Jun 24 2019 - 13:06:21 EST


Sorry, I neglected to add Dan and Johannes--who have been
primary contributors in this discussion--to this. Adding now.

-Alex

On 6/24/19 11:30 AM, Alex Elder wrote:
> OK I want to try to organize a little more concisely some of the
> discussion on this, because there is a very large amount of volume
> to date and I think we need to try to narrow the focus back down
> again.
>
> I'm going to use a few terms here. Some of these I really don't
> like, but I want to be unambiguous *and* (at least for now) I want
> to avoid the very overloaded term "device".
>
> I have lots more to say, but let's start with a top-level picture,
> to make sure we're all on the same page.
>
> WWAN Communication
> Channel (Physical)
> | ------------------------
> ------------ v | :+ Control | \
> | |-----------| :+ Data | |
> | AP | | WWAN unit :+ Voice | > Functions
> | |===========| :+ GPS | |
> ------------ ^ | :+ ... | /
> | -------------------------
> Multiplexed WWAN
> Communication
> Channel (Physical)
>
> - The *AP* is the main CPU complex that's running Linux on one or
> more CPU cores.
> - A *WWAN unit* is an entity that shares one or more physical
> *WWAN communication channels* with the AP.
> - A *WWAN communication channel* is a bidirectional means of
> carrying data between the AP and WWAN unit.
> - A WWAN communication channel carries data using a *WWAN protocol*.
> - A WWAN unit implements one or more *WWAN functions*, such as
> 5G data, LTE voice, GPS, and so on.
> - A WWAN unit shall implement a *WWAN control function*, used to
> manage the use of other WWAN functions, as well as the WWAN unit
> itself.
> - The AP communicates with a WWAN function using a WWAN protocol.
> - A WWAN physical channel can be *multiplexed*, in which case it
> carries the data for one or more *WWAN logical channels*.
> - A multiplexed WWAN communication channel uses a *WWAN wultiplexing
> protocol*, which is used to separate independent data streams
> carrying other WWAN protocols.
> - A WWAN logical channel carries a bidirectional stream of WWAN
> protocol data between an entity on the AP and a WWAN function.
>
> Does that adequately represent a very high-level picture of what
> we're trying to manage?
>
> And if I understand it right, the purpose of the generic framework
> being discussed is to define a common mechanism for managing (i.e.,
> discovering, creating, destroying, querying, configuring, enabling,
> disabling, etc.) WWAN units and the functions they implement, along
> with the communication and logical channels used to communicate with
> them.
>
> Comments?
>
> -Alex
>