Skype has used its Interop keynote slot to call for traditional PBX vendors to make their gear more interoperable, despite itself having faced criticism over the closed nature of its own software.

In particular, Skype wants support for Skype calls that come in to businesses using PBXs that support Session Initiation Protocol (SIP) trunking, says Stefan Oberg, general manager and VP of Skype for Business "This is an area where we'd like to co-operate with you," he said.

Skype has announced its Skype for SIP capability that would make the link between its calls and corporate PBXs. Oberg was seeking co-operation to make interoperability easier for corporate customers. Skype has also issued Skype for Asterisk, which allows Skype client software to be used as softphones in businesses, which use open-source Asterisk IP PBXs.

Oberg says the company is building a stable of channel partners who will sell Skype to businesses and also is developing a premium support service that businesses require in order to ensure uptime for their communications. That will include local tech support with staff that speaks the local language, he says.

The company is also working on a business control panel, software that will enable a business to buy Skype credit and distribute it among individual users within the business.

Oberg says the main attraction of Skype for corporations is savings. Calls between Skype peers is free, as is video and conference calling among Skype clients. The company charges for connecting calls to the traditional public phone network.

Business benefits would also include better productivity. He says Skype uses a permanent video call between two of its offices that is displayed on a screen near water coolers in both offices. "We are changing the water-cooler conversation. We are making it international," he says.

Skype can be embedded in third-party applications to enable, for example, click to call support for Microsoft Outlook directories.

Skype announced its business push earlier this year, but Oberg acknowledged that many potential customers remain unaware of its effort.