IMPSAT Becomes First Latin American Carrier for STAR TAP International Exchange September 20, 2000 BUENOS AIRES, ARGENTINA - IMPSAT Fiber Networks, Inc. (‘IMPSAT’ or the ‘Company’) (NASDAQ: IMPT), a leading provider of broadband data transmission and private telecommunications services in Latin America with operations in the United States, today announced that STAR TAP (Science, Technology, And Research Transit Access Point), has designated IMPSAT as a ‘Distributed STAR TAP’ provider, after its remarkable achievement of directly connecting the first Latin American institution (REUNA, Chilean National Universities Network) to STAR TAP’s Chicago-based location. STAR TAP is the premier global exchange point for advanced international networking; it is managed by the University of Illinois at Chicago and operated by Ameritech Advanced Data Services (AADS) in Chicago, Illinois. With this new status and its facilities in the United States, IMPSAT can now offer Research and Educational (R&E) institutions in Latin American access to STAR TAP, enabling them to peer with other advanced networks from Canada, Asia, Europe and Russia, as well as the American Next-Generation Internet (NGI) and Internet2 networks. Currently, there are three carriers with the status of Distributed STAR TAP provider worldwide, and IMPSAT is the first Latin American carrier to offer interconnection services to the AADS Network Access Point (NAP) in Chicago. STAR TAP’s National Research Network partners are: CA*net3 (Canada), CERN (European Laboratory for Particle Physics), CERNET (China), IUCC (Israel), MIRnet (Russia), NORDUnet (Nordic countries), SURFnet (The Netherlands), RENATER2 (France), SingAREN (Singapore), APAN (Asia-Pacific), and TANet2 (Taiwan). In the U.S., both UCAID / Internet2 Abilene connect, as well as U.S. NGI networks, which include: vBNS (NSF), ESnet (Dept. of Energy), DREN (Dept. of Defense), and NREN / NISN (NASA), are connected to STAR TAP. Through IMPSAT, Latin American universities and research centers will benefit from communicating with leading research institutions worldwide at significantly higher transmission speeds, thus allowing for enhancing enhanced knowledge sharing and scientific collaboration. Ricardo Verdaguer, IMPSAT’s chief executive officer, stated, “Since we signed a contract with REUNA to provide connectivity to STAR TAP one month ago, we have worked extensively in developing the quality standards that would guarantee the service required. Today, STAR TAP confirms the success of those efforts and, through IMPSAT, Latin America can now enjoy the benefits of global research interconnection. We are very proud of this major accomplishment in our race to provide world-class Internet access to the region”. “We welcome IMPSAT’s commitment to provide providing a Distributed STAR TAP service. Our goal is to make it easier and more cost-effective for Latin American advanced research networks to connect to the STAR TAP infrastructure in Chicago, facilitating collaboration with American scientists,” said Tom DeFanti, STAR TAP Principal Investigator. IMPSAT Fiber Networks, Inc. is a leading provider of Internet and private network integrated data and voice telecommunications services in Latin America. IMPSAT is building an extensive pan-Latin American high-capacity broadband network using advanced technologies, including IP / ATM switching, DWDM, and non-zero dispersion fiber optics; the Company is also developing a strategy to build state-of-the-art data centers in the Region. IMPSAT provides services to more than 2,100 national and multinational companies, government entities and wholesale services to carriers, ISPs and other service providers throughout the region. The Company currently has operations in Argentina, Colombia, Venezuela, Ecuador, Mexico, Brazil, the United States, Chile and Peru. STAR TAP, Science, Technology, And Research Transit Access Point, is a persistent infrastructure, whose aim is to facilitate the long-term interconnection and interoperability of advanced international networking in support of applications, performance measuring, and technology evaluations. STAR TAP is made possible by major funding from the National Science Foundation, awards ANI-9712283 and ANI-9980480, to the University of Illinois at Chicago. For more information, see www.startap.net. STAR TAP and Distributed STAR TAP are service marks of the Board of Trustees of the University of Illinois at Chicago Statements made in this press release that state IMPSAT’s intentions, beliefs, expectations, or predictions for the future are forward-looking statements. It is important to note that the company’s actual results could differ materially from those projected in such forward-looking statements. Information concerning factors that could cause actual results to differ materially from those in the forward-looking statements is contained in the company’s filings with the U.S. Securities and Exchange Commission (SEC). Copies of these filings may be obtained by contacting IMPSAT or the SEC. Contact: Guillermo Jofré, chief financial officer Gonzalo Alende Serra, investor relations IMPSAT Fiber Networks, Inc. ph: +54.11.4363.3700 or +54.11.4363.3546 John McInerney / Robin Weinberg, investor relations Jenna Focarino / Kathy Purcell, media relations Citigate Dewe Rogerson Inc. ph: +1.212.688.6840 www.impsat.com
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