Microsoft and Japanese peripheral and device maker I-O Data Device Inc. have updated their patent-protection pact.

On September 29, Microsoft announced that I-O Data had signed an updated licensing agreement with Microsoft that covers I-O Data's Linux and Android-based devices.

Neither company is disclosing financial or other specifics about the agreement.The only revelation that's in Microsoft's press release: "This agreement includes I-O DATA network-attached storage devices and routers, as well as tablets."

This isn't the first patent agreement between Microsoft and I-O Data. In 2010, Microsoft and I-O Data signed a patent agreement via which I-O Data paid Microsoft an undisclosed sum for I-O Data's products running Linux and other related open source software.

I-O Data is one of nearly two dozen companies with which Microsoft has signed patent-protection agreements involving Linux, ChromeOS and/or Linux devices. In some, fairly rare occassions, Microsoft has sued and/or countersued Android and Linux vendors, including Kyocera, Barnes and Noble and Samsung, over alleged violations of Microsoft patented technologies in their devices.