A method and arrangement is provided for the multicasting of streaming digital content to a plurality of Internet users. Streaming digital audio, video or other digital data content that is to be multicast to Internet users is formatted into IP protocol at a head-end content source transmission site. The streaming IP digital data is transmitted from the head-end transmission site to at least one distant/remote routing station of an Internet service provider (i.e., a provider-edge router or Internet point of presence) via a bandwidth portion of a digital communications data transport service or transmission medium that is substantially unaffected by conventional Internet communications traffic. The Internet service provider (ISP) maintains at least one access router for providing Internet access via its Internet domain for its customers accessing the Internet via conventional two-way IP connection. The streaming IP digital data received from the content source transmission site by the ISP routing station may then be multicast via the IPS's existing infrastructure to one or more of its Internet access customer.