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                                                                    EXHIBIT 99.1
                                                                   PRESS RELEASE



PRESS CONTACTS:                                INVESTOR RELATIONS CONTACT:

Jim Brady                                      Blair Christie
Cisco Systems, Inc.                            Cisco Systems, Inc.
(408) 853-3168                                 (408) 525-4856
jambrady@cisco.com                             blchrist@cisco.com

Amy Hughes
Cisco Systems, Inc.
(408) 525-8471
amhughes@cisco.com

                      CISCO SYSTEMS TO ACQUIRE OKENA, INC.

   Acquisition Extends Cisco's Network Security Portfolio with Next-Generation
                           Endpoint Security Solution

      SAN JOSE, Calif., January 24, 2003 - - Cisco Systems, Inc., today
announced a definitive agreement to acquire privately-held Okena, Inc. of
Waltham, Mass. Okena's next-generation network security software provides threat
protection for desktop and server computing systems, also known as "endpoints,"
by identifying and preventing malicious behavior before it causes harm. With the
addition of Okena's endpoint security software, Cisco will offer its customers
the most comprehensive network security threat protection portfolios for
securing large corporate networks. The acquisition of Okena enhances Cisco's
leadership in the rapidly growing market segment for networking security.

      Under the terms of the agreement, Cisco common stock worth an aggregate
value of approximately $154 million will be exchanged for all outstanding shares
and options of Okena. In connection with the acquisition of Okena, Cisco expects
a one-time charge for purchased in-process research and development expenses not
to exceed $0.01 per share. The acquisition of Okena is expected to close in the
third quarter of Cisco's fiscal year 2003. The acquisition has been approved by
the board of directors of each company and is subject to various closing
conditions.

      "The acquisition of Okena reinforces Cisco's commitment to leadership in
the network security market and is part of a significant initiative to more
tightly integrate network and
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endpoint security," said Richard Palmer, vice president and general manager,
Cisco Virtual Private Network and Security (VSEC) Business Unit. "By removing
endpoint vulnerabilities, Okena's preventive software solution enhances the
overall security, availability and integrity of corporate networks."

      Okena's technology extends beyond conventional desktop and server security
solutions. Rather than relying on signature-based techniques, Okena technology
intercepts all operating system, file system, configuration, registry, and
network requests, preventing malicious activity from occurring. This unique,
behavior-based approach provides customers robust protection and reduces
operational costs.

      Okena's security software aggregates and extends multiple endpoint
security functions - Host-based Intrusion Detection (HIDS), distributed
firewall, malicious code protection and operating system lockdown - in a single,
integrated solution. Additionally, because it protects against Day Zero viruses
and worms, Okena's technology is complementary to conventional desktop
Anti-Virus solutions.

      The acquisition of Okena further enhances Cisco's comprehensive security
portfolio of network-integrated solutions and appliances for Virtual Private
Networks (VPN), firewalling, intrusion protection, and security management.

      Okena was founded in 1999. Okena's 52 employees will join the Cisco
Virtual Private Network and Security Business Unit under the direction of
Richard Palmer.

ABOUT CISCO SYSTEMS

      Cisco Systems, Inc. (NASDAQ: CSCO) is the worldwide leader in networking
for the Internet. News and information are available at www.cisco.com.

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Cisco, Cisco Systems, and the Cisco Systems logo are registered trademarks of
Cisco Systems, Inc. and/or its affiliates in the U.S. and certain other
countries. All other trademarks mentioned in this document are the property of
their respective owners.

