

	Mexican National Carrier Protel Chooses iBasis As IP Carrier First Carrier to Provide International VoIP Services in Mexico to Expand Global Footprint via The iBasis Network Burlington, Mass.-April 12, 2000-iBasis, Inc., (Nasdaq: IBAS), the leader in advanced Internet-based communications, today announced that Operadora Protel, S.A. de C.V., "Protel", one of Mexico's leading national carriers, has signed a VoIP (Voice-over-Internet-Protocol) service agreement with iBasis. With today's announcement, Protel becomes the first Mexican telecommunications carrier to provide VoIP-based international service in Mexico. As part of this service agreement with iBasis, Protel will be able to route international voice and fax calls over the iBasis Network™, the world's largest international Cisco Powered Network™ for VoIP, and provide iBasis with direct access to Protel's own extensive Cisco Powered Network, which spans all of Mexico. In 1999, the US-Mexico route was the second largest telecom traffic route in the world -- with more than 4.2 billion minutes of voice and fax traffic carried between the two countries.* Protel, a leading Mexican national carrier, provides long distance and other telecommunications services to commercial customers throughout Mexico. Protel has deployed a national fiber optic Cisco Powered Network. Protel currently serves 51 cities in Mexico and Central America. "As the first Mexican carrier to offer international services using VoIP, we sought to leverage this new technology to quickly and efficiently meet our customers' rising demand for broader international service, while ensuring the highest possible quality," said Pablo Ruiz Galindo, CEO of Protel. "For Protel, the partner of choice was clear since iBasis is the only VoIP carrier with both a global footprint and the proven ability to reliably deliver toll quality service to the world's largest carriers." "Protel is one of the new, forward-looking national carriers that understands the strategic advantages that a VoIP network can offer," said Charles V. Giambalvo, senior vice president of iBasis. "With more than 60 international carriers, including 11 of the top 12 US international carriers as customers, we can offer access to our global footprint with no compromise in quality." The iBasis Network™ The iBasis Network™ is the world's largest international Cisco Powered Network™ (CPN) for Internet telephony. iBasis is the only Internet telephony carrier that guarantees service quality by offering the industry's first Service Level Agreement (SLA) for VoIP (Voice-over-Internet-Protocol). The key to maintaining the high level of quality required by the world's largest carriers is the company's proven, proprietary Assured Quality Routing™ (AQR™) technology. At the company's 24 x 7 Network Operations Center (NOC), the nerve center of the iBasis Network, located at iBasis' global headquarters in Burlington, Massachusetts, USA, engineers continuously monitor the global circuit-switched (PSTN) and packet-switched (IP) networks to ensure the highest quality of service to customers worldwide. iBasis has a long-standing strategic relationship with Cisco, as an alliance partner, an ecosystem partner, and one of only 21 Cisco service provider global accounts. About Protel Protel, one of Mexico's leading long distance companies, was founded in 1995. Protel provides long distance services to commercial customers throughout Mexico, operates one of the country's largest international long distance gateways and has licenses to carry telecom traffic to the US, Mexico, Central America and the rest of the world. Protel has its own national fiber optic Cisco Powered Network. Protel currently serves 51 cities in Mexico. Protel has offices in the major cities of Mexico and two international offices (in Guatemala and in Dallas, Texas.) Protel can be found on the Internet at www.protel.net.mx. About iBasis Founded in 1996, iBasis (Nasdaq: IBAS) is the leader in advanced Internet-based communications. iBasis has built the world's first global IP network that delivers toll quality voice and fax service and other advanced hosted communications solutions, including VoCore, to global tier one carriers and other service providers. The iBasis Network™ is the world's largest international Cisco Powered Network for Internet Telephony. iBasis customers include more than 60 international carriers, including 11 of the top 12 US international carriers. The company can be reached at its worldwide headquarters in Burlington, Mass., USA at 781-505-7500 or on the Internet at www.ibasis.net. *Total traffic on this route for the year 1998, Telegeography, Inc., 1998. Except for historical information, all of the expectations, projections and assumptions contained in the foregoing press release constitute forward-looking statements under the Private Securities Litigation Reform Act of 1995 and involve risks and uncertainties. Important factors that could cause actual results to differ materially from such forward-looking statements include, but are not limited to, the considerations described as "Risk Factors" in iBasis' prospectus dated March 9, 2000, and the company's other SEC filings. iBasis, The iBasis Network and Assured Quality Routing are registered trademarks of iBasis, Inc. Cisco and Cisco Powered Network are registered trademarks of Cisco Systems, Inc.