Exhibit 21.1 Incorporation or Subsidiary Organization - ---------- ----------------- Carrier 1 International GmbH Switzerland Telecommunikation Carrier 1 GmbH Austria Carrier 1 Belgium SPRL Belgium Carrier 1 Holding Sarl France Carrier 1 France Sarl France Carrier 1 Holding GmbH Germany Carrier 1 GmbH & Co. KG Germany Carrier 1 Beteiligungs GmbH Germany Carrier 1 Fiber Network Beteiligungs GmbH Germany Carrier 1 Fiber NetworkGmbH & Co. oHG Germany Carrier 1 UK Ltd. Great Britain Carrier 1 Italia Srl Italy Carrier 1 International Management S.A. Luxembourg Carrier 1 B.V. The Netherlands Carrier 1 Nordics AB Sweden Carrier 1 Networks GmbH Switzerland Carrier 1, Inc. Delaware, the United States of America