nrf52840 mesh 3.1 UUID structure

[melt]

Good day

I moved from Mesh3.00 to mesh 3.1 and I see the way UUID is extracted  is slightly different.

I would like to know when I copy the UUID to use in my project  will it suffice to only copy the node[6]  for identification purposes in a mesh.

/** Structure for pasring UUID */
typedef struct __attribute((packed))
{
    uint32_t time_low;
    uint16_t time_mid;
    uint16_t time_hi_version;
    uint8_t clock_seq_hi_reserved;
    uint8_t clock_seq_low;
    uint8_t node[6];
} uuid_generic_format_t;

I need to keep the  uuid array used for identification purposes on the mesh  as small as possible, as it will accompany the message being transmitted.

thank you 

[Bjørn Kvaale]

I would recommend taking a look at the migration guide in the mesh sdk v3.1.0 folder if you have not already, along with the release notes. In the migration guide, this is written:

### Example UUIDs updated @anchor migration_310_uuid_update

- Removed `mesh_app_uuid_gen()` API to prevent use of non RFC4122 compliant UUIDs.
- Updated `nrf_mesh_configure_device_uuid_reset()` API to make generated UUID compliant with
UUID version 4 as per RFC4122.

#### Required actions
- If your systems rely on the old UUIDs, specify the old UUID in the @ref mesh_stack_init_params_t structure
during stack initialization before updating the firmware of such devices.
- Use @ref mesh_app_uuid_print() API to print the UUIDs in a standard format. When printed as array of bytes,
the UUID may not be understandable by systems that use the string representation of the UUID for parsing.

[melt]

Thanks Bjorn, I understand. But im not to worried about the old UUID parameters.I just wanted to know if the Node[6] ID is good enough for  identification when sending  messages on the mesh. I just want to see where the message originated.

[Bjørn Kvaale]

The uuid_generic_format_t struct is a part of the mesh spec (see link 8 in the mesh profile spec: "RFC4122 - A Universally Uniquie Identifier (UUID) URN Namespace). Therefore, it seems you are required to use all of the variables inside this structure to remain mesh compliant. Also take a look at section 3.10.3 Device UUID in the mesh profile spec for more info: