Vodafone has unveiled a new unified communications service for large enterprise customers that ties together desk phones, PC telephony, messaging and mobile phones.

The operator said that the system will work with a company's existing mobile handsets, rather than requiring an upgrade to smartphones for all staff.

The Vodafone One service will handle call routing for customers, linking the Vodafone network with their IP PBX and other infrastructure such as Microsoft Office Communications Server (OCS) and Microsoft Exchange. Vodafone will also manage the complete infrastructure.

This approach enables staff to have a single phone number across their desk phone, mobile and PC-based telephony client, according to the firm. It also enables voicemails to be managed like emails from within Outlook, and lets staff exchange instant messages on a mobile phone by converting them to SMS.

Vodafone expects customers to see a typical 20 per cent reduction in communications operating costs through Vodafone One. The service will be offered under a minimum three-year contract that includes a fixed per-user monthly call tariff.

According to the mobile operator, customers are looking to unified communications as a way to become more responsive, but they also want to cut costs and deploy a simpler solution.

"It's not just about knitting together fixed and mobile; you need to knit together IP telephony and messaging with mobile," said Jon Rutherford, head of corporate and public sector marketing at Vodafone.

Rutherford claimed that Vodafone's differentiator is that it can offer true single-number capability. "The same number reaches all my phones. It will ring my desk phone, my mobile and on my PC," he said.

Vodafone One can also offer a single directory through integration with a customer's Active Directory Windows domain, and a single voicemail box by integrating with the fixed-line voicemail and Exchange unified messaging.

Users get notification of voicemails on their desk phone, through Outlook, and on their mobile handset, and can deal with them using any of these devices.