Aventail Selects RSA to Encrypt Multiple TCP/IP Applications; Adoption of RSA Security Technology Enables Secure and Private Communication over the Internet.

REDWOOD CITY, Calif.--(BUSINESS WIRE)--March 4, 1997--RSA Data Security Inc., a wholly owned subsidiary of Security Dynamics Technologies Inc. (NASDAQ:SDTI), today announced that Aventail Corp. intends to incorporate RSA encryption technology into its S5 Product Series.

Using RSA's public/private key techniques, Aventail's S5 Product Series -- which consists of Aventail VPN, Aventail Internet Policy Manager and Aventail AutoSOCKS -- will enable secure private communication over public networks.

"The significance of incorporating RSA technology into Aventail's S5 Product Series is that an entire datastream will be encrypted, as opposed to a single application," said Jim Bidzos, president of RSA. "This will provide S5 users with the assurance that all the data from any TCP/IP application will be encrypted."

Aventail's S5 Product Series

Aventail's S5 Product Series is based on the IETF-approved SOCKS v5 security protocol standard, which represents a high level of security and provides comprehensive authentication, encryption, access control, monitoring and logging for internal and external networks.

Aventail VPN allows customers to create secure Virtual Private Networks (VPNs) across the public Internet. The VPN Server supports multiple security standards, such as CHAP, Kerberos, DES and SSL. Aventail VPN allows corporations to leverage the Internet for secure communication and replace remote-access or leased-line infrastructure.

Aventail Internet Policy Manager allows corporations to manage and authenticate their employees' access to the Internet and corporate intranets. Aventail Internet Policy Manager integrates with an organization's existing router or firewall and helps companies control and implement their corporate security policies. It provides a high level of security by providing customizable access controls, client authentication, active content filtering and auditing/reporting modules.

Aventail AutoSOCKS enables client TCP/IP applications to securely traverse existing SOCKS-based firewalls and servers such as Netscape Proxy Server, NEC's PrivateNet, and IBM's Secured Network Gateway. AutoSOCKS provides secure and managed access to external networks for desktop users and to the internal corporate network for mobile and remote users.

"Incorporating RSA's technology into the S5 Product Series will allow corporations to have security capabilities across all applications. Aventail is committed to providing interoperable security systems that seamlessly integrate into a company's existing infrastructure," said Evan Kaplan, president of Aventail Corp. "By selecting RSA's technology, Aventail is now able to offer encryption that is recognized worldwide, making it comfortable for our customers to do business on the Internet."

Developers at Aventail Corp. are using RSA's BSAFE and TIPEM software developers' toolkits to build security into the company's S5 Product Series. BSAFE is a cryptographer's toolkit that provides software developers with multiple algorithms and modules for adding encryption and authentication features to applications. BSAFE includes modules for popular encryption techniques, such as RSA, DES, RC2, and RC4, and also supports digital signatures and certificates.

Availability

The RSA technology will be incorporated into Aventail's S5 Product Series in March. Current versions of Aventail AutoSOCKS, Aventail Internet Policy Manager, and Aventail VPN are available for download at www.aventail.com .

Aventail Corp.

Aventail Corp. develops next-generation Internet security systems. Its software enables corporations to easily manage and strongly secure their intranet and Internet communications. The company's S5 Product Series consists of three core components: Aventail VPN, Aventail Internet Policy Manager and Aventail AutoSOCKS.

The company has offices in Seattle, Wash., and can be contacted by phone 888/SOCKSV5 (762-5785), fax [phone] or email at [e-mail]. Aventail's Web address is www.aventail.com .

RSA Data Security Inc.

RSA Data Security Inc., a wholly owned subsidiary of Security Dynamics Technologies Inc., is the world's brand name for cryptography, with more than 80 million copies of RSA encryption and authentication technologies installed and in use worldwide.

RSA technologies are part of existing and proposed standards for the Internet and World Wide Web, CCITT, ISO, ANSI, IEEE, and business, financial and electronic commerce networks around the globe. The company develops and markets platform-independent developers' kits and end-user products and provides comprehensive cryptographic consulting services.

Founded in 1982 by the inventors of the RSA Public Key Cryptosystem, the company is headquartered in Redwood City. -0-

BSAFE and TIPEM are trademarks of RSA Data Security Inc. Aventail and AutoSOCKS are trademarks of Aventail Corp. All other product and brand names are trademarks or registered trademarks of their respective corporations.

This press release contains forward-looking statements relating to the incorporation of RSA technology into Aventail's S5 Product Series and such statements involve a number of risks and uncertainties. Among the important factors that could cause actual results to differ materially from those indicated by such forward-looking statements are delays in product development, undetected software errors or bugs, competitive pressures, technical difficulties, market acceptance of the incorporation of RSA technology into the S5 Product Series, changes in customer requirements, general economic conditions and the risk factors detailed from time to time in Security Dynamics' periodic reports and registration statements filed with the Securities and Exchange Commission, including without limitation Security Dynamics' Registration Statement on Form S-4 (File No. 333-7265) filed on June 28, 1996.

CONTACT: For RSA Data Security

Patrick Corman, 415/326-9648

[e-mail]

or

Aventail

Deanna Leung, 206/777-5617

[e-mail]