To regulate the interception of certain communications, the monitoring of certain signals and radio frequency spectrums and the provision of certain communication- related information; to regulate the making of applications for, and the issuing of, directions authorising the interceptioonf communications and the provision of communication-related information under-certain circumstances; to regulate the execution of directions and entry warrants by law enforcement officers and the assistance to be given by postal service providers, telecommunication service providers and decryption key holders in the execution  of such directions and entry warrants; to prohibit the provision of telecommunication services which do not have the capability to be intercepted; to provide for certain costs to be borne by certain telecommunication service providers; to provide for the establishment of interception centres, the- Office for Interception Centres and the Internet Service Providers Assistance Fund; to prohibit the manufacturing, assembling, possessing, selling, purchasing or advertising of certain equipment; to create offences and to prescribe penalties for such offences; and to provide for matters connected therewith.