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EXHIBIT 23.1
CONSENT OF INDEPENDENT CERTIFIED PUBLIC ACCOUNTANTS
We have issued our reports dated February 4, 2000, accompanying the financial
statements and schedule included in the Annual Report of AppliedTheory
Corporation on Form 10-K for the year ended December 31, 1999 which are
incorporated by reference in this Registration Statement. We consent to the
incorporation by reference in the Registration Statement of the aforementioned
reports and to the use of our name as it appears under the caption "Experts".
/s/ GRANT THORNTON LLP
New York, New York
October 23, 2000
