Purpose of the Weightless SIG Subgroups

One of the key objectives of the Weightless SIG is to develop and then finalise Weightless Standards.

Development of the Standards is enabled by working groups within the Weightless SIG structure. Groups are currently established for the Applications Layer, MAC Layer, PHYsical Layer, Regulatory, Security and Test & Certification topic areas together with a Specification Review Sub-Group. Other Sub-Groups will be formed as required.

Each Sub-Group has a chairperson and other formal positions as necessary. The drafting Sub-Groups provide Change Request documents for Weightless Specifications at quarterly Plenary Meetings/Developers Conferences, at which proposed changes and additions to Specifications are set out.

The input from each of the Sub-Groups is considered at the latter meetings, giving all Members an overview of changes proposed and the opportunity to debate any changes of concern, in particular those that have implications beyond the Sub-Group that drafted them.

Sub-Group participation is open to Core and Promoter Members. Participation in Sub-Group activity is an important part of the democratic structure of open standards organisations. All groups interested in proposing technology revisions to Weightless standards need to join as Core Members. Members may nominate representatives for any and all Sub-Groups and submit company representatives as candidates for Sub-Group Chair (subject to a democratic process and annual renewal).


The Applications Sub-Group works to identify and characterise M2M Applications suited to the capabilities of Weightless technology and to define the requirements that those applications have of Weightless. For example, specific demands for security or acknowledgements. Apart from assessing the fundamental technical suitability of a multiplicity of applications, the emphasis is on their commercial and operational relevance in the marketplace in the near, medium and longer term.

MAC Layer

The MAC layer sits immediately above the PHY/Physical Layer in the Weightless Communications Protocol stack, with the Applications Layer above the MAC. The work of the MAC Sub-Group defines the functionality integrated into the MAC layer of the Weightless protocol and the interfaces to the two other layers so as to provide a cellular communications model solution based on Weightless technology.

PHY Layer

The physical layer of the Weightless communications technology covers all aspects of the lower layers of the Weightless Communications Protocol stack below the frame structure. This includes modulation, coding, equalisation and synchronisation. This group works to verify PHY proposals and make required changes.


The regulatory Sub-Group undertakes work on an ‘as required’ basis to address specific regulatory requirements relevant to Weightless Standards.


Applications in which Weightless technology is deployed operate securely and without excessive exposure to intentional ‘hacking’ and unintentional disruption by other communications activity in the same or adjacent spectrum. The work of the Security Sub-Group defines the security environment and ensures that appropriate measures are built into the Weightless Standard to enable devices to perform without disruption.

Specification Review

The Specification Review Sub-Group brings harmonisation to writing styles and nomenclature to ensure consistency across documentation and conformity with related standards organisations.

Test and Certification

Test and Certification have intentionally been placed together in a single Sub-Group due to the close interrelationship between them. The work of this Sub-Group includes determining strategies for testing and definition of actual test and certification processes for Weightless network and terminal equipment.