Press Release

Redback Networks Announces First Quarter 2005 Operating Results Revenue Continues to Increase with Strong Growth of SmartEdge Platform Sales

SAN JOSE, Calif., April 20, 2005 — Redback Networks Inc. (NASDAQ: RBAK), a leading provider of broadband networking systems, today announced its first quarter results for the period ended March 31, 2005. Net revenue for the first quarter of 2005 was $34.3 million, up from $32.1 million in net revenue for the fourth quarter of 2004, an increase of seven percent. Net revenue was up $4.1 million, or 14 percent, over the first quarter of 2004. Revenue for the company’s next-generation SmartEdge® product line grew by 16 percent from Q4 2004 and 96 percent from Q1 2004.

“We are pleased with the results of the first quarter and the continued momentum of our next-generation SmartEdge platform for integrated video, voice and data broadband networks,” said Kevin DeNuccio, president and chief executive officer, Redback Networks. “SmartEdge sales have not only driven revenue growth but also have created a significant foothold for us in strategic platform decisions for next-generation broadband among the top carriers in the world.”

GAAP net loss for the first quarter of 2005 was $7.1 million or $ (0.13) per share attributable to common stockholders based on weighted average shares outstanding of 53.5 million, compared to a GAAP net loss of $33.0 million or $ (0.64) per share attributable to common stockholders based on weighted average shares outstanding of 51.4 million in the first quarter of 2004. Non-GAAP net loss for the first quarter of 2005 was $2.9 million or $ (0.05) per share based on weighted average shares outstanding of 53.5 million, compared to a non-GAAP net loss of $7.9 million or $ (0.15) per share for the first quarter of 2004 based on weighted average shares outstanding of 51.4 million. Excluded from the non-GAAP results for the first quarter of 2005 were charges relating to amortization of intangible assets, amortization of stock-based compensation, amortization of the fair value of warrants issued in connection with a lease agreement, accretion of a dividend payable to the preferred stockholders, proceeds from the sale of previously reserved inventory as scrap and partial recovery on certain investments that had been previously written down.

See the attached table for a reconciliation of our non-GAAP results to GAAP results.

Redback Networks will discuss these quarterly results in an investor conference call today at 1:45 p.m. Pacific Time. The conference telephone number is 1-847-619-6368. A live web cast is also available from the investor relations portion of the Redback’s web site, www.redback.com, under Investor Relations. A telephone replay of the conference call will be available later in the day. Replay information will be available at 1-630-652-3018, access code: 11385564. Information on these calls and web cast can also be found on the company’s web site.

About Redback Networks
Redback Networks Inc., a leading provider of next-generation broadband networking equipment, enables carriers and service providers to build Smart Broadband Networks that can deliver simplified, personalized, portable subscriber services to consumers and businesses. The company's carrier-class, consumer-scale SmartEdge Router and Service Gateway platforms for Consumer IP combine subscriber management systems and edge routing and, in conjunction with the NetOp™ Element and Policy Manager platform, provide a powerful, flexible infrastructure for managing both subscribers and value-added services.

Founded in 1996 and headquartered in San Jose, Calif., with sales and technical support centers located worldwide, Redback Networks maintains a growing and global customer base of more than 500 carriers and service providers, including major local exchange carriers (LECs), inter-exchange carriers (IXCs), PTTs and service providers. For more information, visit Redback Networks at www.redback.com.

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REDBACK and SmartEdge are trademarks registered at the U.S. Patent and Trademark Office and in other countries.

Note Regarding Forward Looking Statements
The statements contained in this press release that are not purely historical are forward-looking statements that involve a number of risks and uncertainties, the outcome of which could materially and/or adversely affect Redback’s actual future results. All forward-looking statements included in this document are based upon information available as of the date hereof, and Redback assumes no obligation to update these statements. These risks and other risks relating to Redback’s business are set forth in the documents filed by Redback with the Securities and Exchange Commission (SEC), specifically the most recent report on Form 10-K, Form 10-Q and Form 8-K, and amendments thereto, and the other reports filed from time to time with the SEC.