What are the respective roles of ComCom and OFCOM ?

For the implementation of the legislation on telecommunications, the Commission is the licensing authority, but it may have recourse to the Office and impose directives on it (art. 57, para. 2, LTC). It may also delegate to the Office particular tasks (art. 24a, para. 2, LTC), which are laid down separately by the ComCom decree relating to the law on telecommunications (see allocation of tasks according to the law on telecommunications).

In general, OFCOM prepares the cases handled by ComCom, submits the necessary proposals and implements the Commission's decisions. In this sense, it is the examining and executive body in the sphere of regulation of the telecommunications market.
ComCom has permanently delegated to OFCOM the granting of those radio licences which are not the subject of a public tender procedure (e.g. licences for amateur radio operators or for private companies' radio) and which are wholly or primarily intended for the broadcasting of access-authorised radio and television programme services.
OFCOM is also the monitoring authority. It ensures that licensees comply with international law on telecommunications, Swiss law on telecommunications, its implementing provisions and their own licence (see art. 58, LTC). If it becomes aware of a violation of the law in force, the Office makes proposals to ComCom, which will decide on the measures to be taken. The latter may include withdrawal of the licence by the Commission.
For its part, ComCom grants universal service licences and those relating to mobile telephony and other radiocommunication services subject to competitive tendering procedures.
It also acts as the arbitrating body in the event of interconnection disputes.
Finally, it approves the numbering plans and regulates number portability and carrier selection (ComCom Internal Regulations, art. 4).