Starent Networks

(STAR) - Get Report

and its 30% growth rate continue to draw keen investor interest. Funny how a 30% growth rate will do that.

The company, based in Tewksberry, Mass., makes the equipment, called "packet core," that wireless phone companies use to soup up their ability to handle data transfer on their networks.

Verizon

(VZ) - Get Report

and

Sprint

(S) - Get Report

are its main customers.

Jim Cramer, founder of this Web site, trumpeted Starent's stock in his May 8 Mad Money broadcast, despite the stock's relative expense: it currently trades at about 26 times earnings. Still, the company's growth rate and market share of 75% to 80% are attractive, Cramer said. A broader pullback in equities markets, he added, would be a good time to get into the stock.

Shares of Starent were trading higher Monday morning, up 3% at $19.41. The stock has been on a tear since dropping to its 52-week low of $7.30 in November.

In its most-recent earnings report in late April, the company turned in surprise bottom-line growth of 32% and easily cleared Wall Street estimates for the first quarter. Revenue grew at a 30% clip year-over-year, coming in at $73.2 million.

Concerns have been raised, however, about the potential of an 800-pound gorilla entering Starent's cage: Word is that

Cisco

(CSCO) - Get Report

has been developing gear to compete with Starent.

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