Electronic and Postal Communications (Quality of Service) G.N. No. 416 (contd) to such customers simultaneously irrespective of the distance covered and the geographical boundary; “call attempts” means number of calls offered for network processing; “Call Completion Ratio (CCR)” means the ratio of the number of completed calls to the number of call attempts; “completed call” means a call where an answer signal is received; “cellular mobile telephone services” means services derived from a Public Land mobile network; “content service” means service offered for speech or other sound test or images whether still or moving except where transmitted in private communications; “down-time” means the sum of all the time during reporting period when the fault exists on the service; “electronic communication service” means any service the purpose or effect of which is to enable or facilitate electronic communication; “electronic communication services licensee” means an entity engaged in the provision of electronic communication services; “fault” means a state where a network does not meet the service specifications and some repair action is required; “grade of service” means the ratio of lost calls to total call attempts offered to a network during time consistence busy hour of the day; “licensee” means an entity licensed by the Authority to provide communication services; “handover” means the action of switching the call in progress from one radio channel to another without disrupting the call; “operating time” means the total operating time of a service in a network during the reporting period; “postal service” means any service by post; “Public Switched Telephone Network” in its abbreviation “PSTN” means a network set up and operated by basic service licensees for the specified purpose of providing fixed communication services between subscribers using telephone sets or accessories; 4