How do we evolve the IT architecture to enable an ever-increasing set of services while multiple MegaTrends are rapidly transforming the environment? How do you deliver the best possible experience to your users and applications while maintaining agility and keeping cost under control?

Today, in my first blog after the summer break, I'd like to start exploring a topic which is critical to building this new architecture supporting current and upcoming Megatrends -and which can be seen as a Megatrend itself as well: Software Defined Networking (SDN) and the Cisco Open Network Environment (ONE) strategy and architecture.

Bruno Klauser, Consulting Engineer in my team has been focusing on Network Programmability and network-embedded automation for some time -and is currently working with many of the early adopters across EMEAR.

Q: Bruno, with Software Defined Networking  being an increasingly  popular discussion topic we're hearing a lot of of comments -from "nothing new at all" to "complete revolution of IT" -what, if anything, is different from how we built solutions in the past?

Indeed, perceptions and claims around SDN vary widely. If we look at designs and deployments and take a step back to try and look beyond the hype, what's clearly new is the combined focus on three main concepts:

a)      Network Programmability -application interfaces and software development kits such as Cisco onePK allow rich, stateful 2-way interactions with the network at multiple levels of abstraction.

b)      Application oriented control plane architectures -a unified architecture is designed to support use cases instead of retrofitting user needs onto generic application frameworks and network blueprints.

c)       Virtualization of Network (physical and virtual) and Compute -whether a node runs on a shared or dedicated, physical or virtual platform and where that platform resides all become implementation choices for both network nodes as well as application nodes.

The combination of those concepts enables an evolution which allows customers to deliver applications and services in a new way with clear and tangible benefits.

Q: What happened to the often cited SDN concept of separation between control-plane and data-plane?

It's one of multiple choices one can make at the network layer when using a unified architecture  to deliver an IT service -as indicated in b) above.

Historically, IT services have been based on entirely separate designs -often created by different individuals and organizations with different goals in mind -for the physical network, virtual network topologies and software applications.
This separation has allowed internet technologies to very rapidly expand into many domains -but it has also sometimes led to functionality being in the 'wrong' places which introduces unnecessary complexity into the overall architecture. With Virtualization capabilities and Network Programmability, architects now have the opportunity to place functionality where it actually belongs -even moving it freely during operations to accommodate for changes in load and utilization patterns.

Separating the entire control plane and moving it out of the network into a central controller is radically different from how most networks have been built over the last decades, yet as a concept easy to convey -which has stimulated controversy, new thinking and also grabbed a lot of attention. Realistically however, there are many architectural choices between completely distributed or completely centralized control -and real-life scenarios  often combine them. This choice and flexibility is one of the key aspects which we enable with the Cisco ONE Enterprise Network Architecture.

Q: For example ... ?

One frequent example of combined central and decentralized control is used when needing to combine:

• centralized cloud based application logic
• distributed network-aware application logic in remote locations
• application-aware network behavior in those same remote locations

in a way that lets the overall solution dynamically adjust to current conditions in order to deliver the best possible service. This is a pattern we call a Cloud Connector and for which there is already an ecosystem of Cisco and partner-build Cloud Connectors.

Q: Before we dive further into architecture and the Cisco Open Network Environment (ONE) approach, let's step back and look at customer benefits first -why do customers care?

This is in fact an area we get very consistent feedback. Customers care about total cost of ownership (TCO) and return on investment (ROI), complexity and agility. The Cisco Open Network Environment (ONE) lets them address these concerns by evolving the architecture and expanding on concepts which they already know. It also allows them to do so in a simple 3-layer architectural [LF(1] [BK2] concept which can cater to advanced physical, virtual and cloud service environments.

Initially those concerns are often addressed by turning repetitive engineering projects into ongoing operational processes -one of our customers is calling this 'software defined systems integration'. Likewise, further optimization is often achieved when an operational process is opened up for self-service interactions. In the past this has been done for human users via web-based interfaces, now with Cisco ONE this can be done for software applications via programmatic APIs.

This can only be done when the relevant data is available from the network via APIs so that policy decisions can be taken which in turn need to be implemented in the network. By harvesting intelligence at source, implementing decisions in the right place and putting resources where they are needed - all within a simple 3-layer model -the overall complexity becomes more manageable or even decreases.

Figure 1

What we are also seeing is that the ability to offer these IT services more dynamically creates new opportunities for how the companies are doing business -an improvement far beyond just IT cost savings.

Q: How difficult or easy is this for customers to adopt?

The situation reminds me very much of convergences which have already taken place -wired/wireless, data/voice, ATM/MPLS, just to name a few. What customers and partners have started to embrace can be seen as network/software convergence or network/application convergence.

If we look at the people/tools/process  aspects, we see that there are (mega)trends in each aspect supporting the convergence:

• while network and application skills were entirely separate even just a few years ago, nowadays combined skillsets are more readily available with both experienced professionals as well as with graduates newly joining the IT industry
• we've talked about technology already -network programmability, virtualization capabilities and application oriented architectures are moving from the labs into production environments
• operational experience with IT processes leveraging orchestration, network-embedded automation and self-service within reasonable boundaries  has been gained in the industry -just compare how a decade ago static, best-effort network services were provided with how today end-users in a BYOD era interactively consume tailored services and service levels

Also adoption can happen in a familiar setting -let's look at Figure 2 below: already today the IT organization is managing services (a, b, c) and users are using network services (1, 2) or interacting with self-service graphical interfaces (3). Incrementally, customers can leverage the possibility for applications to interact via APIs (3, 4, 5) for specific needs.

Figure  2

So once they get inspired and see the opportunities in context of how they run their business, it's merely an exercise of prioritizing a simple initial scenario -and just doing it.

Q: So as a Customer or Partner, where do I start?

Get inspired by what others have been doing -good starting places are the Cisco ONE website at www.cisco.com/go/one , browse through the recent Cisco ONE exhibits at recent CiscoLive in Orlando or join us for the Cisco ONE learning path at  CiscoLive 2014 in Milan.

Then engage with a few simple candidate scenarios in mind. There is a growing set of partners across EMEAR with Cisco ONE skills and the Cisco Developer Network (CDN) offers plenty of background material and opportunities to engage with the community or learn and pilot in a lab setting.

Finally, when you work on your next project, watch out for opportunities to apply what you've learned and make new solutions happen.

Thanks Bruno!

What will Network Programming and Cisco ONE enable for your business? Which candidate scenarios are you already considering? Please tell us if that is has been useful.

• www.cisco.com/go/one
• www.cisco.com/go/onepk
• developer.cisco.com/web/onepk