In a deal that may signal the start of a new era of competition for entrenched cable and satellite providers, Viacom has tentatively agreed to let its popular cable channels — like Nickelodeon and MTV — be carried by an Internet TV service that Sony is creating.

The agreement is believed to be the first of its kind between a major programmer and any of the technology giants that are trying to disrupt traditional modes of TV delivery. If other programmers follow suit, Sony’s as-yet-unnamed service would let paying subscribers receive live cable channels the same way they use on-demand libraries like Netflix or Hulu. Intel and Google are working on similar services, but try to make it more user-friendly, perhaps the way Netflix does with personalization features and a fancy interface.

Most households today have only a few choices for television service: whatever cable company serves their local area, be it Comcast, Time Warner Cable or others, and two satellite providers, DirecTV and Dish Network. In some parts of the country, television through Verizon or AT&T is also available. Analysts say cable delivered through the Internet could give households many more choices — if the new services give customers more for their money and if cable incumbents don’t smother the services.

To even have a chance, companies like Sony and Intel need the permission of programmers, and that’s why the Viacom deal is considered a breakthrough. Although Viacom and Sony declined to comment on Thursday, a person directly involved in the negotiations confirmed a Wall Street Journal report about the agreement. The person insisted on anonymity because the companies were not prepared to comment on the record.