1 Exhibit 21.1 HARMONIC INC. AND SUBSIDIARIES SUBSIDIARIES OF THE REGISTRANT The following table shows certain information with respect to the active significant subsidiaries of the Company as of December 31, 2000. NAME STATE OR OTHER PERCENT OF VOTING JURISDICTION OF SECURITIES OWNED INCORPORATION BY HARMONIC Harmonic Lightwaves (Israel) Ltd. Israel 100% Harmonic Data Systems Ltd. Israel 100% Harmonic (UK) Ltd. United Kingdom 100% Harmonic Europe S.A.S. France 100% Harmonic Germany GmbH Germany 100% Harmonic (Asia Pacific) Ltd. Hong Kong, China 100% Harmonic Data Systems Inc. U.S.A. 100% Harmonic International Inc. U.S.A. 100%