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                                                                       Exhibit 5




                                                  June 28, 2001

C-COR.net Corp.
60 Decibel Road
State College, PA  16801

                  Re:   Registration Statement on Form S-8
                        ----------------------------------

Ladies and Gentlemen:

          We have acted as special counsel to C-COR.net Corp. (the "Company") in
connection with the registration under the Securities Act of 1933, as amended,
of interests (the "Interests") in the C-COR.net Corp. Retirement Savings and
Profit Sharing Plan (the "Plan") and 950,000 shares of common stock of the
Company, par value $.05 per share (the "Shares"), that may be issued to
participants in the Plan from time to time.

          In rendering our opinion, we have reviewed originals, or copies
certified or otherwise identified to our satisfaction, of the Plan and such
certificates, documents, corporate records and other instruments as in our
judgment are necessary or appropriate to enable us to render the opinion
expressed below (the "Documents"). In giving the opinion set forth below, we
have assumed the following:

     1.   Each individual executing any of the Documents, whether on behalf of
such individual or another person, is legally competent to do so.

     2.   Each individual executing any of the Documents on behalf of a party
(other than the Company) is duly authorized to do so.

     3.   Each of the parties (other than the Company) executing any of the
Documents has duly and validly executed and delivered each of the Documents to
which such party is a signatory, and such party's obligations set forth therein
are legal, valid and binding and are enforceable in accordance with all stated
terms.

     4.   Any Documents submitted to us as originals are authentic. The form and
content of any Documents submitted to us as unexecuted drafts do not differ in
any respect relevant to this opinion from the form and content of such Documents
as executed and delivered. Any Documents submitted to us as certified or
photostatic copies conform to the original documents. All signatures on all such
Documents are genuine. There has been no subsequent oral or written
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modification of or amendment to any of the Documents, by action or omission of
the parties or otherwise.

     5.   The Shares will continue to be duly and validly authorized on the
dates the Shares are issued to participants pursuant to the terms of Plan.

     6.   Upon issuance of any of the Shares, the total number of shares of
Company common stock issued and outstanding will not exceed the total number of
shares of common stock that the Company is then authorized to issue.

     7.   On the date the Interests are created pursuant to the terms of the
Plan, the Interests will constitute legal and binding obligations of the Company
and will (subject to applicable bankruptcy, moratorium, insolvency,
reorganization and other laws and legal principles affecting the enforceability
of creditors' rights generally) be enforceable against the Company in accordance
with their terms.

     8.   No change occurs after the date hereof in applicable law or the
pertinent facts.

     9.   The provisions of the applicable "blue sky" and other state securities
laws have been complied with to the extent required.

          Based on the foregoing, we are of the opinion that: (i) the Interests
created pursuant to the Plan will be legal and binding obligations of the
Company, and (ii) the Shares, when issued in accordance with the terms of the
Plan, will be legally issued, fully paid and nonassessable.

          We consent to the filing of this opinion as Exhibit 5 to the
Registration Statement on Form S-8 being filed with respect to the offering of
the Shares.

          This opinion is limited to the matters expressly stated herein. No
implied opinion may be inferred to extend this opinion beyond the matters
expressly stated herein. We do not undertake to advise you or anyone else of any
changes in the opinions expressed herein resulting from changes in law, changes
in facts or any other matters that hereafter might occur or be brought to our
attention.




                                     Very truly yours,
                                     /s/ Ballard Spahr Andrews & Ingersoll, LLP