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Date:   Thu, 2 May 2019 22:35:26 +0200
From:   "michal.lowas-rzechonek@silvair.com" 
        <michal.lowas-rzechonek@silvair.com>
To:     "Stotland, Inga" <inga.stotland@intel.com>
Cc:     "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>,
        "Gix, Brian" <brian.gix@intel.com>
Subject: Re: [PATCH] mesh: Use node uuids as storage directory names
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Hi Inga,

On 05/02, Stotland, Inga wrote:
> Device UUID is associated with a mesh-based application and, as such,
> is immutable.

> However, the same application (or we can call it device) can be
> simultaneously provisioned on different mesh networks (e.g., home and
> office networks), which means that it needs to be represented as a
> unique mesh node and its configuration has to be stored in unique
> distinct location.  Hence the need for a unique node ID that is not
> based on device UUID.
3.10.3 says that:

"(...) each node shall be assigned a 128-bit UUID known as the Device
UUID. Device manufacturers shall follow the standard UUID format as
defined in [RFC4122] and generation procedure to ensure the uniqueness
of each Device UUID"

So I think the UUID is assigned to *nodes*, not *applications*
controlling them? I don't think it's legal to create two different
nodes with the same UUID.

To cover the use case you mentioned, I think the application would need
to keep track of two UUIDs, and Attach() itself to both - which is
certainly possible.

regards
-- 
Michał Lowas-Rzechonek <michal.lowas-rzechonek@silvair.com>
Silvair http://silvair.com
Jasnogórska 44, 31-358 Krakow, POLAND