The Microsoft POLP

 Despite the name this isn't what might be found by Steve Ballmer's most recent colonoscopy. Instead it stands for Protocol Optimization Licensing Program and it's how Cisco, Riverbed and others work with Microsoft and develop optimization solutions for key Microsoft protocols (e.g., MAPI) without the risk (technical and legal) of having to reverse engineering the base protocol. Riverbed's recent press release talked of this as a "partnership" but that's probably not quite the right word to use (in fact these protocol license documents explicitly say they aren't partnerships because that has specific meaning in Washington State commercial law). Although Microsoft provides access to these protocols they still pretty much control things because of the many patents underlying the protocols. Understanding the protocol doesn't mean you can implement it (because of the patents) nor build "derivative" works (what has to be done for WAN optimization). That only comes with an explicit license agreement (e.g., POLP) that includes a nominal payment and more to the point also gives MS forgiveness on any patent violation they might have doing their own version of the optimized protocol (cross licensing). I'm not sure I would call that a "partnership."