The long speculated tensions among Cisco (CSCO), EMC (EMC) and VMware (VMW) may finally becoming to a head.

It's VMworld week, which means lots of fun in the world of virtualization -- where conflicted partnerships can turn into messy divorces. And the back channels are chattering about the buzz of VMware's new initiatives, notably the intro of EVO:RAIL and EVO:RACK, which pose new threats and questions about its relationship with both Cisco and VMware's majority owner, EMC.

EVO:RAIL and EVO:RACK look a lot like a hardware platform, with VMware and partner software loaded on top of servers and network applicances to create a sort of virtualized and distributed “god box” that handles storage, computing, and networking. This is what they are calling in the biz a “converged infrastructure.” The partners include Dell, EMC, Fujitsu, Inspur, NetONe, and SuperMicro. That's a big list of Cisco competitors -- remember that Cisco is in the server business. This has been VMware's most aggressive foray onto the hardware side, where it's starting to put together a broader story for disaggregation and Software Defined Networking (SDN) with the hardware manufacturers that can help make it happen.

Both Cisco and EMC have intertwined relationships with VMware, but this should be seen as a direct assault on their own hardware markets. They have got to consider the current deals with VMware and where the relationships are going in the future. The thinking from both Cisco and EMC originally was: VMware's got great virtualization software, we've got great hardware. But now that VMware is stepping up its hardware story and Cisco and EMC increasingly being envious of the software market -- with the whole industry headed toward SDN -- it puts pressure on the whole dynamic.

Consider the relationships:

• EMC owns an 80% stake in VMware and has broad product partnerships in the storage space. It has long been speculated that EMC will have to find a way to spin off or sell its stake.
• Cisco owns a small, minority stake in VMware (under 2%)
• Cisco, EMC, and VMware have broad product partnership, including a joint venture called VCE, and VMware is a partner on Cisco's data-center switches.
• VMware bought SDN startup Nicira. Cisco bought SDN startup Insieme. They are two software approaches to networking virtualization, making Cisco's partnerships with VMware more questionable.

VCE is especially problematic for both EMC and Cisco. Vblock, the VCE product, runs on server hardware from Cisco and with storage software from EMC and virtualization software from VMware.

The Vblock infrastructure is called a “converged infrastructure,” because it blends compute, networking, and storage.

VMware calls the new EVO:RAIL platform a “hyperconverged infrastructure.” Hmmm. Close enough, me thinks.

Is there any difference between a converged infrasctructure and a hyperconverged infrastructure? VMware looks like it's competing with VCE now. How can this possibly go over well with Cisco and EMC? Stay tuned. I expect fireworks to ensue shortly.