Press Release

    PHILADELPHIA--(BUSINESS WIRE)--May 12, 2003--

    Harmonic's NMX Digital Service Manager(TM) Facilitates Network
       Problem Resolution and Resource Planning by Service Group

Harmonic Inc. (Nasdaq:HLIT) has enhanced its NMX Digital Service Manager(TM) to provide visual monitoring capabilities for cable operators using Harmonic's industry leading VOD platform. Harmonic's NMX now communicates directly with Narrowcast Services Gateway(TM) (NSG) edge devices to deliver real time information for evaluating the status of the network equipment. The system also provides 24/7 usage reporting, enabling operators to view their network loads by service group -- a set of subscribers sharing the same segment of an HFC network for VOD services -- and time of day. Using NMX, operators can diagnose and resolve network problems faster as well as optimize resource allocation according to the subscriber capacity requirements of a service group.

"The NMX Digital Service Manager allows operators to make informed decisions about how they segment their networks, allocate their resources and market to their subscribers," said Dr. Yaron Simler, President of Harmonic's Convergent Systems Division. "When VOD customers are denied access because of an oversubscribed service group, all they know is that they did not get their movie. The better a network is managed, the less likely that will happen. At the end of the day, satisfied subscribers are the best way to increase revenue."

NMX Presents Visual View and Usage Reports for VOD Networks

Using the NMX template wizard, operators can graphically represent access network elements and their interconnections. Major network elements include video servers, Gigabit Ethernet switches, DWDM transport systems and NSG edge devices. Using this intuitive tool, the time required to diagnosis a device failure or oversubscribed service group is now measured in seconds rather than hours.

Daily and interactive reporting capabilities allow operators to view network usage information for all service groups. Statistics are collected and the data is used to create daily graphical reports that can be automatically e-mailed to a pre-defined user group. An interactive query allows operators to generate reports covering longer periods of time -- ranging from days to months -- in order to gain further insight into network usage trends. These graphical reports help operators understand their network utilization, allowing them to determine purchasing trends of their subscribers and offer incentives for buying services in off-peak hours.

Scalable NMX System Enables Distributed Monitoring of Cable VOD Networks

NMX supports both the remote monitoring of centralized systems and the centralized monitoring of geographically dispersed systems, improving service availability and reducing operational costs. It also provides multi-level security for tight control of management privileges. NMX is based on open standard networking and management technologies, including XML and SNMP, which makes it straightforward to integrate key third party subsystems such as enterprise-wide alarm aggregators. A consolidated view of alarms combined with a unified alarm log facilitates problem detection and troubleshooting, whether the systems are located in close proximity or remotely to the operator.

The NMX Digital Service Manager will be presented in Harmonic's booth (#961) at the SCTE's Cable-Tec Expo.

About Harmonic Inc.

Harmonic Inc. is a leading provider of digital video, broadband optical networking and IP delivery systems to cable, satellite, telecom and broadcast network operators. Harmonic's open standards-based solutions for the headend through the last mile enable customers to develop new revenue sources and a competitive advantage by offering powerful interactive video, voice and data services such as video-on-demand, high definition digital television, telephony and Internet access.

Harmonic (Nasdaq:HLIT) is headquartered in Sunnyvale, California with R&D, sales and system integration centers worldwide. The Company's customers, including many of the world's largest communications providers, deliver services in virtually every country. Visit www.harmonicinc.com for more information.

This press release contains forward-looking statements including, but not limited to, the anticipated features, performance and benefits to customers of the NMX Digital Service Manager and its ability to communicate with the NSG edge device, within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Actual results could differ materially from those projected in the forward-looking statements as a result of the risk factors set forth in documents that Harmonic files with the SEC, including reports on Form 10-K and 10-Q.

EDITOR'S NOTE - Product and company names used here are trademarks or registered trademarks of their respective companies.

    CONTACT: Aries MarketMasters (Media Relations for Harmonic)
             Dawn Danaher, 714/378-5841
             danaher@ariesmarketmasters.com
              or
             StreetConnect (Investor Relations for Harmonic)
             Michael Newman, 408/542-2760
             mnewman@stct.com

    SOURCE: Harmonic Inc.