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Cisco separates switching and routing software from hardware

Open networking finally comes to Switchzilla as IOS XR, IOS XE, Nexus OS added to disaggregation strategy

Cisco has taken a long, hard look at the biggest bullet in its kit, and bitten down: the company has announced it will separate its router and switch software from the hardware that hosts it.

The “kill-your-darlings” decision is in response to demand from hyperscale Web outfits and service providers, rising sales of white-box OEMs, and growing competition from software-only “niche vendors”, Switchzilla said in its announcement.

The decision marks a huge reversal on former CEO John Chambers's view of the world. Early in the days of disaggregation and white-box offerings, Chambers stuck to his guns, saying customers wanted the company to respond to their business needs in ways that “point product” vendors could not.

Switchzilla first dipped its toe in the new software-defined world with its Enterprise Network Compute System, which early last year became a fully-fledged NFV (network function virtualisation) solution. At that time, Cisco also unveiled its first virtual customer premises equipment product.

Now, Cisco is adding:

  • A software-only IOS XR product for service providers;
  • Enhancements to its IOS XE; and
  • The Nexus OS also split from its hardware.

Cisco said the disaggregated IOS XR allows the software to run on Cisco or merchant silicon-based switches and routers, or as a virtualised instance on x86-based clouds. It's also available on “specific” third party devices as explained here (the Edgecore Networks AS7816-64X 100GbE data center switch is first off the rank).

As engineer Sumeet Arora wrote here, the company has also expanded IOS XR's APIs.

“Specifically, we are adding to our Model-driven programmability and the recently announced Service Layer API,” Arora wrote, with an Open Forwarding Abstraction API offering “a logical representation of all the forwarding and telemetry capabilities of the underlying hardware. Developers use these capabilities to specify the packet forwarding and processing treatment they want from the data plane and provide a hardware-agnostic mapping function to other network software stacks written for a specific forwarding abstraction or data plane paradigm.”

Enterprise IOS XE

IOS XE customers with a yen for DevOps get a bunch of templates to help them along.

As Sachin Gupta explained here, the Cisco Validated Design (CVD) Configuration Management Templates for IOS XE “automate deployment of Cisco reference designs through the use of declarative configurations.”

The first template in the catalogue is an Ansible playbook for campus LAN Layer 2 access (at GitHub).

Catalyst 9000 switches and ISR/ARS routers both get application hosting capabilities – essentially, server space on the switches that can host applications in Linux containers or as KVMs. This will launch with IOS XE 16.8.1.

In the data centre

For data centre customers, as the company's Roland Acra wrote, there's a “cloud scale” SAI (switch abstraction interface) that lets the switch run other vendor's operating systems.

Acra says Microsoft has already bolted its SoNIC network operating system onto its Nexus 9200 and 9300 platforms, and quotes Microsoft Azure Networking CVP Yousef Khalidi as saying it means Redmond and cloud operators can use “the same software stack across a variety of switch hardware platforms”.

A virtual NX OS offering lets customers simulate their clouds, testing “anything from new features and the transitional fabric state during upgrades through the software upgrade impact on existing tooling environment for their actual large-scale topologies.”

+Comment: Cisco resisted disaggregating its core networking products despite having been a central player in previous such shifts across other product categories.

For example, go back a decade or more, and the company was one of the driving forces behind the push to replace monolithic PABX with software-driven IP telephony.

However, its in-house silicon, tightly bound to the software above it, remained too valuable for too long, even though in the 2014 Cisco Live! speech we linked to above, John Chambers admitted the company was moving too slowly.

It will take some time – at least a couple of quarters – to assess the impact on the company's financials. Chamber's replacement Chuck Robbins had to endure many disappointing quarters before putting on a grin to announce the Q2 2018 results – and the Catalyst 9000 was identified as one of the key growth drivers for the quarter.

In February, Robbins said that the C9000's success was down to a new licensing model that tied subscriptions to value-add on the hardware.

The company's next challenge will be to keep that momentum going in a world where customers might start running its software on less costly platforms. ®

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