The Sunnyvale, California-based company, a chief rival of Cisco Systems Inc, said revenue grew 46% to $546.4m from $375m a year ago.

Profit came in at $84.1m, or 14 cents a share, versus $48.8m, or 8 cents, last year.

At the top of many investors’ minds was Juniper’s security business, which earlier this year had lower-than-expected performance after Juniper acquired firewall/VPN vendor NetScreen Technologies Inc in April 2004 for about $3.5bn.

During the last quarter, ended September 30, however, its security business grew organically by 8% sequentially and more than 37% year-over-year, said chief executive Scott Kriens, on a conference call.

That’s more than double the growth rate of most of the security peers we see in the market, he said. The growth we see is sustained and sustainable.

Revenue rose in Juniper’s security business across its product range and was actually pretty balanced across geographies and customer types, including both enterprises and service providers, Kriens said.

Combined revenue for security, J-Series Services routers and session border controllers totaled $109.3m, a 17% jump from last quarter, said CFO and EVP of business operations Robert Dykes, on the call.

Regarding the competitive landscape, Kriens said Juniper was in a unique situation and we realize it. It’s really quite unusual actually because we’re strengthening our position in a growing market while at the same time the number of qualified competitors are shrinking, he said. Most of Juniper’s rivals are burdened with legacy investments, he said. We’re not smarter than anyone else but we do have the freedom to focus on the future.

Not surprisingly, infrastructure products drove the bulk of revenue, or 65%, and grew more than 36% year-over-year. However, the network core represented more than half of its business during the quarter, whereas in the previous quarter the edge of the network represented more than half, Dykes said.

Enterprise business now accounts for about one third of Juniper’s total revenue, including routing, security, application and acceleration products, Dykes said.

Kriens said the trend toward triple play services continued to be a growth driver for the company. It’s seems more of a priority for customers every day, he said. Competition among service providers was fuelling demand, he said. KPN and Korea Telecom are among Juniper customers that are moving to triple-play offerings.

Siemens remained Juniper’s largest customer and accounted for more than 10% of revenue during the quarter.