Tiscali is to offer broadband telephony and video-on-demand services to residential customers across Europe.
The pan-European ISP is working with French IP Centrex provider NetCentrex to provide the technology for the service.
Olivier Hersent, chairman of NetCentrex, said: "This agreement will enable Tiscali to provide all of its one million ADSL [Asymmetric Digital Subscriber Line] users with IP telephony services."
Tiscali has been in talks with NetCentrex for about a year. Craig Thomas, the firm's market strategist, said: "We do not currently offer our business customers broadband telephony.
"First, the Centrex model is harder to implement than simply installing equipment. Second, the key to voice over DSL is quality of service [QoS]. We will be enabling QoS on our DSL connections and across our virtual private networks to our network in the next month or so."
Tiscali plans to roll out its consumer service for voice calls over the internet in Italy in September, with a video-on-demand offering to follow.
The service is expected in the UK but the company could not specify when.
AlwaysOn launched its IP Centrex offering on 10 February. Representative George Zaremba said: "NetCentrex is very focused on mainland Europe.
"Inclarity and Dimension Data have both gone for the platform, but we really haven't seen much of them. Dimension Data in particular has been very quiet after signing with NetCentrex a year and a half ago.
"Tiscali is a formidable company. Sheer size makes it a serious competitor in this market."
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