iBasis, a Burlington, Mass., provider of Internet telephony services, has signed Telenor, a Norway telecommunications carrier, as a customer. Financial terms were not disclosed.

With the agreement, Telenor will route international voice traffic over iBasis' network. Founded in 1855 as the Norwegian Telegraph Administration, Telenor has expanded its services, reach and customer base, which in 2000 included more than 2 million mobile subscribers.

Telenor was the first service provider to introduce SmartPhones, which provide mobile Internet services to ordinary phone subscribers.

For its part, iBasis expands the volume of traffic it carries to and from the markets served by Telenor and subsidiaries in Europe and Southeast Asia.

"This interconnection to Telenor's global network complements our already extensive presence in Europe and South Asia and will help us grow the volume of Tier 1 traffic we carry to and from these important regions," said Ofer Gneezy, iBasis' president and CEO.

Shares of IBAS rose 0.24, or 15 percent, to 1.79 at midday. In the last 52 weeks, the issue has ranged from 0.36 to 9.8125.