As Cisco prepares for its Cisco Live conference, being held next week in San Francisco, it's also preparing for general availability of its Application-Centric Infrastructure (ACI), supposedly by the end of June. So, it seems a sensible time for the company to roll out a few more ACI-related announcements, trying to keep the platform front-and-center for customers (and investors) at the conference.

This morning, Cisco is announcing its strategy for linking ACI to data-center fabrics based on the Nexus 2000 and Nexus 7000 lines. Cisco is also announcing a few new Nexus 9000 switches to the ACI pile.

Cisco has a lot riding on ACI, certainly in terms of business but also in terms of pride. So high is the company's confidence in ACI that CEO John Chambers has actually started using the term "SDN." I'm don't mean that as a joke; in recent years, you'd never hear Chambers utter those letters. Now that Cisco thinks it can take a lead in SDN — now that SDN is no longer just a weapon for VMware and other competitors — the term has entered his vocabulary.

On the company's earnings call Wednesday, Chambers noted 1,000 ACI customers in the pipeline — although, as we pointed out, most of them aren't yet testing the waters with SDN. Only about 70 customers are beta-testing ACI in simulation, which is the only way the full product is available at the moment. (Chambers said 50 customers on Wednesday; it's likely he was just using an outdated count.)

Cisco says it's gathered 33 industry partners to work with ACI. Chances are, nearly all of them will be on hand in San Francisco to show (or at least talk about) how their products work inside or alongside an ACI framework — as noted in this Cisco blog entry.

And Cisco swears ACI will be an open framework, with some parts available as open-source code — including the data models for policy.

That's important because policy is what drives ACI. The Application Policy Infrastructure Controller (APIC) tells network devices what it wants accomplished, letting the devices decide how to do the job. Cisco's OpFlex protocol provides an interface for communicating policy information but doesn't say anything about how to create those policies.

"We do intend to go fully open in terms of what the data model looks like," says Jacob Jensen, Cisco's senior director of product management. The data model should be available right around the time the APIC starts to ship (i.e., before June 30); Cisco didn't immediately have information as to whether it would be available through Cisco's site, Github, and/or other sources.

Cisco has taken a few other steps toward openness. OpFlex, the protocol for delivering policies, has been accepted as a project within the OpenDaylight Project. And a Group Based Policy blueprint, crafted by several companies including Cisco, has been accepted into OpenStack.

In launching ACI last year, Cisco said the architecture will be extended to the entire portfolio. Cisco is taking the first and probably simplest step in that direction by explaining how a data center running older Nexus switches can participate in ACI.

This is not about ACI configuring the legacy network. It's just about keeping old and new networks in sync, policy-wise.

"You still have to configure and manage your existing network the way you do today," Jensen says. "What ACI will do is make sure the policy is consistent" between that legacy network and a new ACI fabric built of Nexus 9000s.

The plan requires two pieces — a Nexus 9300 top-of-rack switch and the Application Virtual Switch (AVS), a derivative of the Nexus 1000v virtual switch created for ACI. The APIC will talk to those two elements, and they'll act as the first hop into the legacy network.

This is pretty much the same setup that would be used to connect the APIC to a newfangled ACI-based fabric, so it's not exactly a stunning revelation. The point was more to say that Cisco is aware that ACI differs from any other Nexus-based network and that there's a plan to draw the two together.

Cisco is also tying its Unified Computing System (UCS) to the APIC. The new Version 5.0 of the UCS Director software adds the Nexus 9000 switches as one of the resources it can orchestrate. UCS Director will also be able to communicate endpoint information to the APIC, so it can see what services are available or possible in the network.

Later, this capability could be exploited so that UCS could send telemetry information to the APIC, giving the APIC some intelligence as to where the resources are available for placing applications, Jensen says.

Finally, Cisco is releasing some new hardware to go with ACI:

• The Nexus 9396PQ. Some people at Cisco have taken to calling it the "baby spine." With 36 40-Gb/s ports, it's a smaller version of a Nexus spine switch.
• The Nexus 9396TX, a new leaf or top-of-rack switch with 48 ports of 10-Gb/s copper interconnect. Other Nexus 9300s of this size support only fiber.
• The Nexus 9736PQ, a line card for the modular Nexus 9700 switches, sporting 36 40-Gb/s ports.

Cisco is also announcing several other small features for the Nexus portfolio. The most interesting among them: VXLAN support is now available on the Nexus 3000, 5000, 6000, 7000, and 9000 lines.

(Photo of San Francisco by Sudheendra Vijayakumar on Flickr, Creative Commons 2.0 license.)