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April 23 (Reuters) - Network equipment maker F5 Networks Inc posted a higher-than-expected quarterly revenue and forecast third-quarter results largely above analysts' estimates, helped by increased demand from its telecom customers.
Shares of the company, whose customers include AT&T Inc and Verizon Communications Inc, rose about 3 percent in extended trading.
F5's quarterly revenue rose 20 percent, partly as its U.S. telecom clients beef up their networks to allow faster transfer of data-heavy files on smartphones and tablets.
In the past year, F5 has launched upgrades to its software and introduced hardware that help manage traffic on networks. These products have found favor with customers.
AT&T has estimated capital expenditure of about $21 billion for this year, while Verizon has said it expected to spend about $17 billion. (http://r.reuters.com/nag78v)
F5, whose rivals include Cisco Systems Inc and smaller peer Riverbed Technology Inc, forecast adjusted earnings of $1.33-$1.36 per share and revenue of $428 million-$438 million for the third quarter ending June 30.
Analysts on average were expecting a profit of $1.33 per share on revenue of $428.7 million, according to Thomson Reuters I/B/E/S.
F5's net income rose to $69.6 million, or 91 cents per share, in the second quarter ended March 31 from $63.4 million, or 80 cents per share, a year earlier.
Revenue rose to $420 million from $350.2 million a year earlier.
Excluding items, F5 earned $1.27 per share.
Analysts on average had expected a profit of $1.25 per share on revenue of $414.4 million.
F5's rival Juniper Networks Inc also reported a higher-than-expected 10 percent rise in quarterly revenue on Tuesday as its U.S. telecom clients spent more to ramp up their networks.
F5's shares closed at $108.19 on the Nasdaq on Wednesday.
(Reporting by Lehar Maan in Bangalore; Editing by Kirti Pandey)