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                                  EXHIBIT 5

             OPINION AND CONSENT OF BROBECK, PHLEGER & HARRISON LLP


                                  May 25, 2000

ACT Networks, Inc.
26707 West Agoura Road
Calabasas, California  91302

               Re:     ACT Networks, Inc. Registration Statement for Offering
                       of an Aggregated of 490,000 Shares of Common Stock

Ladies and Gentlemen:

               We have acted as counsel to ACT Networks, Inc., a Delaware
corporation (the "Company"), in connection with the registration statement on
Form S-8 (the "Registration Statement") under the Securities Act of 1933, as
amended, of an (i) additional 200,000 shares of common stock, par value $.001
per share, of the Company ("Common Stock") authorized for issuance under the
Company's 1997 Stock Incentive Plan (the "Incentive Plan") (ii) 200,000 shares
of Common Stock issuable pursuant to the stock option granted to Mr. Sadr on
February 10, 2000 (the "Sadr Option") and (iii) 90,000 shares of Common Stock
issuable pursuant to the stock option granted to Mr. Weisman on February 23,
2000 (the "Weisman Option").

               This opinion is being furnished in accordance with the
requirements of Item 8 of Form S-8 and Item 601(b)(5)(i) of Regulation S-K.

               We have reviewed the Company's charter documents and the
corporate proceedings taken by the Company in connection with the amendment of
the Incentive Plan and the grant of the Sadr Option and the Weisman Option.
Based on such review, we are of the opinion that, if, as and when the shares of
the Company's Common Stock are issued and sold (and the consideration therefor
received) pursuant to (i) the provisions of the option agreements duly
authorized under the Incentive Plan or pursuant to the provisions of the Sadr
Option or the Weisman Option and in accordance with the Registration Statement
or (ii) direct stock issuances duly-authorized under the Incentive Plan and in
accordance with the Registration Statement, such shares will be duly authorized,
legally issued, fully paid and non-assessable.

               We consent to the filing of this opinion letter as Exhibit 5 to
the Registration Statement.

               This opinion letter is rendered as of the date first written
above, and we disclaim any obligation to advise you of facts, circumstances,
events or developments which hereafter may be brought to our attention and which
may alter, affect or modify the opinion expressed herein. Our opinion is
expressly limited to the matters set forth above, and we render no opinion,
whether by implication or otherwise, as to any other matters relating to the
Company, the Incentive Plan or the Sadr Option or the Weisman Option or the
shares of the Company's Common Stock issuable under the Plans or the Option.

                                                Very truly yours,


                                                BROBECK, PHLEGER & HARRISON LLP

