Nippon Telegraph and Telephone Corp. announced Thursday it plans to launch fixed-rate Internet access for its ISDN users later this year.

Under the proposed trial, users can spend unlimited amounts of time accessing their Internet providers for about 10,000 yen a month.

NTT plans to introduce the new services in the Osaka and Tokyo regions around November and is considering expansion into other areas in the future.

Current subscribers to NTT's integrated services digital network use two telephone lines, one for ordinary conversation and one for Internet access, under one phone number.

NTT currently has 2.86 million ISDN subscribers it regards as frequent Internet users, and some 10 percent of them pay about 10,000 yen a month for the service. These are the people NTT is targeting for the new service, the carrier said.

For ISDN subscribers who do not use the Internet as frequently, NTT will launch a discount service that allows users to make local calls for Internet access at a fixed rate for a certain amount of time.

For example, NTT is considering a charge of about 1,000 yen a month for 15 hours of access and roughly 3,000 yen a month for up to 30 hours.

Also, NTT plans to reduce long-distance rates this fall through three brackets that effectively cover calls of between 20 km and 100 km.