425

===============================================================================

                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED):

                                FEBRUARY 15, 2007

                      INTERNAP NETWORK SERVICES CORPORATION
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

          DELAWARE                   000-31989                91-2145721
(STATE OR OTHER JURISDICTION  (COMMISSION FILE NUMBER)      (IRS EMPLOYER
      OF INCORPORATION)                                  IDENTIFICATION NUMBER)

     250 WILLIAMS STREET, ATLANTA, GA                      30303
 (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)                (ZIP CODE)

       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (404) 302-9700

                                 NOT APPLICABLE
          (FORMER NAME OR FORMER ADDRESS, IF CHANGED SINCE LAST REPORT)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

[X]   Written communications pursuant to Rule 425 under the Securities Act (17
      CFR 230.425)

[X]   Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
      240.14a-12)

[ ]   Pre-commencement communications pursuant to Rule 14d-2(b) under the
      Exchange Act (17 CFR 240.14d-2(b))

[ ]   Pre-commencement communications pursuant to Rule 13e-4(c) under the
      Exchange Act (17 CFR 240.13e-4(c))

================================================================================



ITEM 8.01. OTHER EVENTS

Internap issued a press release, dated February 15, 2007, which is attached as
Exhibit 99.1.

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS

EXHIBIT NO.  DESCRIPTION
- -----------  -----------

99.1         Press Release issued by Internap, dated February 15, 2007



                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                 INTERNAP NETWORK SERVICES CORPORATION

Date: February 15, 2007

                                 By:  /s/ David A. Buckel
                                      ----------------------------------------
                                      David A. Buckel, Chief Financial Officer



                                  EXHIBIT INDEX

99.1   Press Release, dated February 15, 2007

EX-99.1

[INTERNAP LOGO]                                                     EXHIBIT 99.1

                                                           FOR IMMEDIATE RELEASE

                INTERNAP TO HOLD SPECIAL MEETING OF STOCKHOLDERS

                    Announces Details for Remote Participants

ATLANTA, GA - FEBRUARY 15, 2007 - Internap Network Services Corporation (NASDAQ:
INAP), a leading provider of performance-based routing solutions over the
Internet, today announced details of its special meeting of stockholders on
Tuesday, February 20, at 3 p.m. EST. Only stockholders of record on that date
are entitled to vote at the meeting. At the meeting, shareholders will vote on
one proposal, which is approval of Internap's issuance of approximately 11.9
million shares of Internap's common stock in connection with its announced
intent to acquire VitalStream Holdings, Inc.

The meeting will be held at Internap's offices at 250 Williams Street NW, Suite
E-100, Atlanta, Georgia. Stockholders may also participate via conference call
by dialing 1-800-599-9829; participant passcode 69180463. International callers
may dial 01-617-847-8703; participant passcode 69180463.

A live audio Web cast of the presentation will be available on the investor
relations section of Internap's Web site at
http://www.internap.com/investor/presentations/page1294.html. Internap will

also provide access to a replay of the Web cast following the call.

The information about the special meeting and the transaction in this release is
neither a solicitation of a proxy, an offer to purchase nor a solicitation of an
offer to sell shares of Internap's common stock. Any offer of securities will
only be made pursuant to the Joint Proxy Statement/Prospectus on Form S-4 filed
with the Securities and Exchange Commission ("SEC") by Internap and VitalStream,
a copy of which is available without charge on the SEC's website at www.sec.gov.

A free copy may also be obtained from Internap or VitalStream through their
Investor Contacts listed below.

ABOUT INTERNAP

Internap is a market leader of intelligent route control solutions that bring
reliability, performance and security to the Internet. The company's patented
and patent-pending technologies address the inherent weaknesses of the Internet,
enabling enterprises to take full advantage of the benefits of deploying
business-critical applications such as e-commerce, VoIP, and audio/video across
IP networks. Internap currently serves more than 2,200 customers throughout
North America, Europe, Asia and Australia. For more information, please visit
the company web site at www.internap.com.

Internap is a trademark of Internap Network Services. All other trademarks and
brands are the property of their respective owners.

CONTACTS: INTERNAP
Media Contact:
L.A. Campbell
404/302-9721
lcampbell@internap.com

Investor Contact:
Andrew Albrecht
404/302-9841
aalbrecht@internap.com