Australian mobile network operator Telstra has become the first to introduce a mobile broadband service using HSPA+ at 42Mbps.

The company states that though Internet speed of 42Mbps is only theoretical, users can expect "typical download speeds ranging from 1.1M bps to 20Mbps." Ericsson, the manufacturer of the HSPA+ (High Speed Packet Access+) equipment, said that users can experience peak speeds of up to 30Mbps.

The fastest theoretical speed on offer from operators using previous HSPA+ equipment is 21Mbps. To reach 42Mbps mark, Telstra is making use of modem and mobile network vendors to implement a technology called dual carrier. The solution allows networks to send and receive wireless data using two channels simultaneously.

The dual carrier HSPA+ rollout is being slowed down by the availability of modems. Telstra currently 2,000 Sierra Wireless modems based on a chipset from Qualcomm. Telstra will sell market the solution to business customers under the "Ultimate USB Modem" brand.

The company's Ultimate USB Modem is tied into a number of different mobile broadband plans, including paying nothing up-front on a AUD$69 monthly plan for 24 months.