The bloom between Apstra and Cisco—both of whom offer intent-based networking (IBN) solutions—has definitely withered.

Up until this year, Apstra was a Cisco Partner, and an invited attendee at the Cisco Live! conferences, but that has changed, according to Apstra's Michael Wood, CMO and vice president of product.

"This year they shut us out," Wood said. "They completely denied us. They've come back and said that 'You're not allowed at Cisco Live, and you're no longer a Cisco partner.'"

(After this story published, Wood said that he misspoke. Apstra has not been completely denied. Apstra will be attending Cisco Live!, but won't be an exhibitor. He also said Apstra's relationship with Cisco is unchanged and that Apstra works with Cisco across a range of technology fronts.)

Wood said there could be several reasons why Cisco changed course. The first is that Cisco Application Centric Infrastructure (ACI) customers are showing up at Apstra's door.

"So, what's happening is that we have now have Cisco ACI customers coming to us and asking us to help because of the complexity, and the lack of intent-based networking capabilities within ACI," Wood said. "They have actually asked us to come in and provide orchestration. And, of course, that ACI model locks you into Cisco, and Cisco hardware, whereas our model allows these customers to expand and use other alternatives. So, that's one big driver.

"And, then the other thing is that we've come up against ACI now in quite a few new opportunities, and we're winning. I think that has raised a lot of red flags within Cisco."

ACI is Cisco's SDN architecture that combines hardware and software for automation in cloud and data center environments. While Apstra is a neutral platform, Cisco requires the use of its hardware, such as its Nexus 9000 family of switches, for ACI.

“A flaw in Cisco’s software ACI orchestration architecture is that to enable the bulk of functionality, it requires Cisco hardware," said Scott Raynovich, founder and chief analyst of Futuriom. "The true nature of software-defined networking is that it works in a multivendor hardware environment, so customers are going to favor orchestration tools that can work over a variety of hardware platforms. Apstra is well positioned to do that."

While Apstra and Cisco both offer IBN solutions, they come at it from different ends of the spectrum. Apstra first used the term "intent-based networking" when it came out of stealth mode in 2016. In 2017, Cisco introduced intent-based networking with launch of its new DNA Center. Other vendors, such as Huawei and Juniper Networks, have also jumped on the IBN bandwagon.

"It reminds me a lot about SD-WAN when I was at VeloCloud," Wood said "Over time, everybody had an SD-WAN sticker that they were putting on their products and looking to fit into that SD-WAN definition. We're seeing the same thing with intent-based networking."

IBN is a software driven automation model that allows an administrator to set the desired outcomes for network orchestration. Based on those policies, IBN can automate the provisioning and configuration of services while also managing application services.

For Apstra, IBN starts with a "single point of truth," that is one database, which Apstra calls a Graph Datastore, that holds all of the data for underlays and overlays in a network as well as profiles of all of the devices. Apstra defines the single point of truth as Level 1, which includes self operation. Level 2, which is where Apstra is today, includes "real time change validation" to check that configuration has been performed and implemented to conform with the intended strategy. Level 3 moves towards self-automation for the network.

"The idea here is that I can completely take my hands off the wheel, theoretically, and the system just operates on its own," Wood said of Level 3. "Now, Apstra has been architected for Level 3, and we operate today at Level 2, but we're beginning to move to the Level 3 capabilities that allow the system to operate on its own. "

On the other hand, Cisco has thrown the weight of its entire portfolio behind IBN. During Cisco's third-quarter earnings call earlier this month, Cisco CEO Chuck Robbins said his company has rebuilt its entire access portfolio with IBN in mind across wired and wireless. Over the past several years, Cisco has also been working to integrate IBN into its enterprise access portfolio "to help our customers manage more users, devices, and things connecting to their networks," Robbins said.

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And, while Cisco turned in a mostly solid third quarter, Wood, who worked for Cisco for 15 years, questioned Cisco's IBN approach.

"The proof is in the architecture, and whether or not the actual solutions are able to deliver on the promise of intent-based networking," Woods said. "You have to have a single source of truth, that's just the core requirement. Cisco has got multiple tools with multiple databases. You can't go to one tool and one database to find everything. You have to correlate those and that correlation requires human intervention. So, now, suddenly, a human becomes your networking orchestration. They have dozens, if not hundreds of people, looking at all this information to correlate it."

Apstra rolls out 3.0 OS

Last month, Apstra launched version 3.0 of its Apstra Operating System (AOS) at Dell Technologies World. New features for 3.0 include a more advanced VMware vSphere connection, increased scale of IP Clos fabrics with support for an additional layer of “super spines” for building larger pods with a unified management plane and intent-based analytics enhancements.

"So, 3.0 is most significant and comprehensive release that we've introduced our first launch of the product in 2016," Wood said.

Editor's note: Wood contacted FierceTelecom on Friday to say that Apstra will be attending Cisco Live! in June but will not be an exhibitor. He also said via email that Apstra's relationship with Cisco was unchanged and that they collaborate across other areas.