JULY 27, 2004, PETALUMA, CALIFORNIA—Calix today announced that it has commenced volume delivery of new ADSL2+ interfaces on the market-leading Calix C7 platform. In addition to being one of the first access network elements to make ADSL2+ generally available, the Calix C7 ultra-broadband loop carrier (UBLC) is the only such platform with the capacity to drive all ADSL2+ ports at peak line rates on a sustained basis. With 200 Gbps of capacity in a compact form factor, the packet-based Calix C7 supports 2,400 ADSL2+ ports in a single seven foot rack and as many as 1,920 ADSL2+ ports from its line of patented outdoor cabinets. Individual ADSL2+ ports can be clocked at downstream speeds as high as 24Mbps and will typically support services consuming 15Mbps of bandwidth at loop lengths of about 8Kft.

With advanced compression technologies such as H.264 / MPEG-4, Part 10 and Microsoft's Windows Media Player 9—and even with many existing MPEG-2 encoders—wireline service providers are now able to deliver HDTV programming along with multiple standard quality video streams, tiered Internet access, and packet voice over existing copper infrastructure.

According to Tom Corker, Calix vice president and general manager for access products, "ADSL2+ represents an enormous step forward for wireline service providers looking to extract additional utility from existing copper plant while paving the way for FTTP. In addition to providing ample bandwidth for multi-stream video, VOD, and HDTV, it dramatically increases the range of possibilities for tiered Internet access offerings and substantially increases upstream capacity."

CenturyTel [NYSE: CTL], the eighth largest ILEC in the United States based on access lines, is among the first Calix customers to deploy services based on ADSL2+. "The benefits of ADSL2+ are more pronounced in rural areas where distance is a factor," Tim Walden, vice president of engineering for CenturyTel, said. "CenturyTel specializes in bringing advanced product offerings and services to our consumer and business customers in primarily rural areas and smaller cities, where speed and reach are critical."

The Calix ADSL2+ line card fits seamlessly into existing Calix C7 deployments and is backward compatible with all existing ADSL CPE. In addition to supporting significantly higher downstream transmission rates, ADSL2+ supports higher upstream rates as well—an increasingly important attribute as web traffic becomes more symmetric. The Calix C7 platform allows service providers to migrate to FTTP connections while also supporting ADSL2+ connections, delivering an identical service set to subscribers over dissimilar ultra-broadband access media.

About Calix
Calix is a leading supplier of telecommunications solutions designed to simplify all aspects of voice, data, and video service delivery to business and residential subscribers for local exchange carriers of all sizes. Providing extensive optical and metallic density, unprecedented access capacity and functional headroom, advanced management and provisioning capabilities, and broad service flexibility, the packet-based Calix C7 platform has been deployed in over 125 service provider networks throughout North America. More information about Calix can be found at www.calix.com.

This press release contains forward-looking statements that are based upon management's current expectations and are inherently uncertain. Forward-looking statements are based upon information available to us as of the date of this press release and we assume no obligation to revise or update any such forward looking statement to reflect any event or circumstance after the date of this release. Actual results and the timing of events could differ materially from current expectations.

For additional information contact:
Jacquelyn Dara
Calix
O: 707-766-3337
M: 415-572-3272
E: jdara@calix.com