Attached files

file filename
10-K - 10-K - COGENT COMMUNICATIONS HOLDINGS, INC.a2202298z10-k.htm
EX-23.1 - EX-23.1 - COGENT COMMUNICATIONS HOLDINGS, INC.a2202298zex-23_1.htm
EX-31.1 - EX-31.1 - COGENT COMMUNICATIONS HOLDINGS, INC.a2202298zex-31_1.htm
EX-31.2 - EX-31.2 - COGENT COMMUNICATIONS HOLDINGS, INC.a2202298zex-31_2.htm
EX-21.1 - EX-21.1 - COGENT COMMUNICATIONS HOLDINGS, INC.a2202298zex-21_1.htm
EX-32.2 - EX-32.2 - COGENT COMMUNICATIONS HOLDINGS, INC.a2202298zex-32_2.htm

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Exhibit 32.1


Certification of Chief Executive Officer

        Pursuant to 18 U.S.C. § 1350, as created by Section 906 of the Sarbanes-Oxley Act of 2002, the undersigned officer of Cogent Communications Group, Inc. (the "Company") hereby certifies, to such officer's knowledge, that:

    (i)
    the accompanying Annual Report on Form 10-K of the Company for the year ended December 31, 2010 (the "Report") fully complies with the requirements of Section 13(a) or Section 15(d), as applicable, of the Securities Exchange Act of 1934, as amended; and

    (ii)
    the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: February 28, 2011

    /s/ DAVID SCHAEFFER

David Schaeffer
Chief Executive Officer

        The foregoing certification is being furnished solely to accompany the Report pursuant to 18 U.S.C. § 1350, and is not being filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be incorporated by reference into any filing of the Company, whether made before or after the date hereof, regardless of any general incorporation language in such filing.




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Certification of Chief Executive Officer