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                                                                    Exhibit 99.1

            CLARENT ANNOUNCES ACQUISITION AGREEMENT WITH ACT NETWORKS
              COMBINED COMPANY TO OFFER BROAD SUITE OF INTELLIGENT
                          CONVERGED TELEPHONY PRODUCTS

REDWOOD CITY AND CALABASAS, CALIF.-MAY 1, 2000- CLARENT(TM) CORPORATION (NASDAQ:
CLRN), a worldwide leader in providing carrier-grade, phone-to-phone Internet
Protocol (IP) telephony solutions, today announced the signing of a definitive
agreement to acquire ACT Networks, Inc. (Nasdaq: ANET). ACT Networks is a
leading provider of multi-service access and voice/data integration products
that enable the convergence of voice, video and data onto one managed network.

Under the terms of the agreement, each outstanding share of ACT Networks will be
exchanged for 0.2546 of a share of Clarent Common Stock. The exchange ratio will
be subject to a `collar' providing a maximum and minimum value of Clarent Common
Stock to be exchanged for each share of ACT Networks at Closing of $18.00 and
$14.00, respectively. Based on Clarent's closing price on Monday, May 1st, 2000
the company will issue approximately $189 million of stock for the outstanding
shares of ACT in addition to assuming ACT Networks' outstanding stock options.

The acquisition has been approved by the boards of directors of both companies
and is expected to close in the third quarter of 2000. This transaction is
subject to various closing conditions, including approval by ACT Networks'
stockholders and termination of the necessary waiting period under the
Hart-Scott-Rodino Act.

"Both Clarent and ACT Networks have pursued this transaction because of the
strong belief that synergies exist between our firms' products and business
strategies" stated Jerry Chang, CEO and President, Clarent Corporation. "We
believe that integration of our product solutions will help service providers
and their enterprise customers migrate to and build more scalable,
cost-effective, end-to-end IP telephony networks. Overall, we believe this
business combination allows Clarent to continue to enhance our leadership
position in the service provider market."

"We believe that both companies have demonstrated leadership and strong customer
momentum in the marketplace," said ACT CEO and President Andre de Fusco. "We
expect that our channel, service provider and large enterprise partners will
look to the combined company as the leading supplier of full-featured IP-based
convergent network solutions. By offering a broad portfolio of voice and data
access equipment, fully integrated command and control software, and
state-of-the-art value-added services, we have the further opportunity to bridge
the gap between in-place legacy voice and data networking systems, and the next
generation IP-based service deployment infrastructure."

Clarent is acquiring ACT to expand its product portfolio to include a
comprehensive suite of data networking service access equipment, to increase
product options available to its service provider customer base, to enhance its
development capabilities, and to blend Clarent's current predominantly direct
sales model with ACT's channel driven distribution strategy.


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ACT Networks is expected to become a wholly-owned subsidiary and will continue
to be headquartered in Calabasas, CA. Andre de Fusco, 42, President and CEO of
ACT Networks, will join Clarent's management team as President of the ACT
Networks Division.

Thomas Weisel Partners served as financial advisor to Clarent in this
transaction. ACT was represented by Dain Rauscher Wessels.

FORWARD-LOOKING STATEMENTS

This news release contains forward-looking statements that involve risks and
uncertainties that could cause actual results or outcomes to differ materially
from those contemplated by the forward-looking statements. Factors that could
cause or contribute to such differences include, but are not limited to, risks
relating to the consummation of the contemplated merger, including the risk that
required regulatory clearances or stockholder approval might not be obtained in
a timely manner or at all. In addition, statements in this press release
relating to the expected benefits of the contemplated merger are subject to
risks relating to the timing and successful completion of technology and product
development efforts, integration of the technologies and businesses of Clarent
and ACT Networks, unanticipated expenditures, changing relationships with
customers, suppliers and strategic partners and other factors described in the
most recent Form 10-Q, most recent Form 10-K and other periodic reports filed by
each company with the Securities and Exchange Commission.

ADDITIONAL INFORMATION AND WHERE TO FIND IT

Clarent plans to file a Registration Statement on SEC Form S-4 in connection
with the merger, and Clarent and ACT Networks expect to mail a Proxy
Statement/Prospectus to stockholders of ACT Networks containing information
about the merger. Investors and security holders are urged to read the
Registration Statement and the Proxy Statement/Prospectus carefully when they
are available. The Registration Statement and the Proxy Statement/Prospectus
will contain important information about Clarent, ACT Networks, the merger and
related matters. Investors and security holders will be able to obtain free
copies of these documents through the website maintained by the U.S. Securities
and Exchange Commission at http://www.sec.gov. Free copies of the Proxy
Statement/Prospectus and these other documents may also be obtained from Clarent
by mail to Clarent Corporation, 700 Chesapeake Drive, Redwood City, California,
94063, Attention: Investor Relations, telephone: (650) 817-3999.

In addition to the Registration Statement and the Proxy Statement/Prospectus,
Clarent and ACT Networks file annual, quarterly and special reports, proxy
statements and other information with the Securities and Exchange Commission.
You may read and copy any reports, statements or other information filed by
Clarent or ACT Networks at the SEC public reference rooms at 450 Fifth Street,
N.W., Washington, D.C. 20549 or at any of the Commission's other public
reference rooms in New York, New York and Chicago, Illinois. Please call the
Commission at 1-800-SEC-0330 for further information on the public reference
rooms. Clarent's and ACT Networks' filings with the Commission are also
available to the public from commercial document-retrieval services and at the
web site maintained by the Commission at http://www.sec.gov.



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SOLICITATION OF PROXIES; INTERESTS OF CERTAIN PERSONS IN THE MERGER.

ACT Networks will be, and certain other persons named below may be, soliciting
proxies from ACT Networks stockholders in favor of the adoption of the merger
agreement. The directors and executive officers of ACT Networks and the
directors and executive officers of Clarent may be deemed to be participants in
ACT Networks' solicitation of proxies.

The following are the directors and executive officers of ACT Networks:

NAME                       POSITION
----                       --------

Andre de Fusco             President, Chief Executive Officer, and Director

William W. Ambrose         Director

Archibald J. McGill        Director

Frederick W. Gluck         Director

Robert Musslewhite         Director

Dave Weisman               Vice President, Marketing

Alain Gravel               Vice President, Engineering

Robert J. Faulk            Chief Financial Officer and Vice President, Finance

Eric Grubel                Vice President, Worldwide Sales

Ramin Sadr                 Chief Technology Officer




The following are the directors and executive officers of Clarent:

NAME                       POSITION
----                       --------

Jerry Shaw-Yau Chang       Chief Executive Officer, President and Director

Michael F. Vargo           Senior Vice President, Chief Technology Officer
                           and Director

William R. Pape            Director

Wen Chang Ko               Director


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Syaru Shirley Lin          Director

Richard J. Heaps           Chief Operating Officer, Chief Financial Officer,
                           General Counsel and Secretary

Mark E. McIlvane           Senior Vice President, Worldwide Sales

Heidi H. Bersin            Senior Vice President, Corporate Marketing
                           and Communications

Mong Hong (Mahan) Wu       Senior Vice President and General Manager,
                           Asia Pacific

Peter K. Bohacek           Senior Vice President, Business Development
                           and Product Marketing

The directors and executive officers of ACT Networks have interests in the
merger, some of which may differ from, or may be in addition to, those of ACT
Networks' stockholders generally. Those interests include:

*     in connection with the merger, Andre de Fusco, Alain Gravel, and certain
      key engineers have entered or will enter into employment and
      noncompetition agreements with Clarent;

*     certain of the directors and executive officers of ACT Networks may own
      options to purchase shares of ACT Networks common stock which will become
      vested and exercisable in connection with the merger;

*     certain of the directors and executive officers of ACT Networks are
      covered by severance plans that are triggered in connection with the
      merger; and

*     Clarent has agreed to provide indemnification and director and officer
      liability insurance coverage to the directors and executive officers of
      ACT Networks following the merger.

ABOUT CLARENT CORPORATION

Clarent Corporation is a premier provider of scalable, IP telephony products to
carriers and Internet service providers around the world. Clarent's intelligent
architecture and the Clarent Command Center enable Clarent products to route,
manage, inter-connect and terminate high volumes of calls for service provider
customers including the world's largest long distance telecommunication
companies. According to an iLocus report published in 1999, more minutes travel
across Clarent-enabled networks worldwide than those of any other equipment
supplier.*

Founded in July 1996, Clarent is headquartered in Redwood City, California and
has offices in major cities in Asia, Europe, Latin America and North America.
Additional information about Clarent is available at www.clarent.com.

                                      # # #

Clarent is a registered trademark of Clarent Corporation in the United States
and other jurisdictions. All other company or product names mentioned may be
trademarks or registered trademarks of the respective companies with which they
are associated.


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* "IP Telephony Clearinghouses A New Business Model". Published November 1999 by
iLocus. iLocus, a division of Cape Saffron Ltd., is an UK-based research group
focused on the IP telephony industry. www.ilocus.com

ACT Networks and NetPerformer are registered trademarks and ServiceXchange and
PowerCell are trademarks of ACT Networks.


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