High Level Design (HLD):

DeviceSYS generates, delivers and maintains, a design document (HLD) for the project at hand. Customer requirements are translated to architecture and top level design. Next, top level design is further detailed to a level that is appropriate for experienced developers to implement the design.

HLD is indeed a product. It can be given to a design house for bidding and implementation. It is a basis for a test plan. The owner of the HLD retains intellectual property (HLD) rights. HLD can also serve as part of a contract between a customer and a design house or a manufacturer.

Typical HLD may include some or all of:

Project/product requirements

Derived requirements enumerated for traceability

Use cases

Overall architecture - device to/from cloud

Data security

System performance and limitations

Solution scaling

Hardware block diagram

RF and antenna design

Component selection

Battery life calculations

Costed Bill Of Materials - BOM

Firmware block diagram

State machine diagram

Firmware modules and interfaces

Messages and sequence diagrams

Cloud / Host software design

Project plans 

Manufacturing plan

Deployment (pre, during and post)