A more holistic view of IT architecture, encompassing cloud, security and your network, can transform your organisation.

By David Pratt, head of discovery practice at BT Consulting

The past few years have been challenging for IT departments due to the pressure to modernise business infrastructure and support new ways of working. After rapid cloud adoption in 2020, organisations are now slowing their IT investments as they navigate out of the pandemic and find their footing in a shifting marketplace.

As business spend tightens, each piece of the technology puzzle is coming under greater scrutiny, with technology like SD-WAN increasingly seen as too expensive. But this siloed approach to IT risks leaving organisations with piecemeal technology set-ups that compromise security and hold them back from realising the full benefits of capabilities like hybrid cloud.

Shining a spotlight on SD-WAN

Despite the hype around SD-WAN and its capabilities, investment decisions still regularly come down to cost. Organisations regularly make the mistake of creating Service Integration and Management (SIAM) silos – separating budgets and decisions into traditional, specialised areas. This restricted view isolates SD-WAN from other technical innovations transcending the network. And regional, local, and decentralised decision-making misses SD-WAN’s value as part a wider architecture encompassing cloud, security and the network.

Approaching the IT estate as an ecosystem sidesteps this and provides a more holistic overview of technical investments. Savings delivered in one area through rationalisation, efficiency, or simplification, for example, provide funds for investment in another. Seemingly unviable investments then become realistic as part of a broader infrastructure transformation programme that can be more ambitious and generate more significant results.

Building the business case for SASE

Secure Access Service Edge (SASE) is the ‘as-a-service’ convergence of WAN edge and secure edge. Rather than one ‘thing’ that organisations can price and procure, it requires investment across multiple areas, taking into account policy, capability, and business outcomes.

SASE investment recognises that network, cloud and security need to be viewed collectively, with as much ‘as-a-service’ technology deployed as possible – from SD-WAN to secure web gateways, firewalls, cloud access brokers and even Zero Trust architecture to introduce greater scalability, agility and pace.

Developing a single, upfront infrastructure investment case for SASE is the best way to ensure a strategic approach, while also sidestepping the need for multiple business cases. It enables organisations to create an overarching roadmap that clearly outlines savings and outlays. Through this lens, decisions about technology like SD-WAN are less focused on cost and more on longer-term strategy.

Breaking down the business case

It all sounds good in theory, but where should an organisation start? Ideally, the business case should consider a wider criterion for SD-WAN than overlay alone. For example, organisations should consider:

* Overlay: When it comes to total cost of ownership (TCO), in our experience only 25% of infrastructure cost relates to overlay. By choosing the cheapest SD-WAN option, businesses are potentially depriving themselves of important features offered by more premium services, without securing significant cost benefits. Simply put, it’s a bad trade-off.

* Underlay: The remaining 75% of cost comes from underlay, so it has a greater impact on TCO than vendor choice. In the hunt for cost-savings, some organisations offset bandwidth costs using cheaper Internet, but it’s important to think about performance and security when considering this route.

* Bandwidth: Future bandwidth requirement has a huge impact on performance, underlay and overlay choice. Combined with underlay transformation, all overlays show cost savings with 0% bandwidth increase. However, zero is unrealistic. A 100% uplift is far more realistic over a 3-5-year period and in some industries up to 200% is achievable. This impacts the point where the TCO breaks even and can increase overall costs.

* SLA/service: This is critical to end user experience and is tied to both underlay transformation and overlay choice. Apps are the lifeblood of an organisation, so delivering these where they are needed, on demand, and to the approved users is essential. The decision should be centred around balancing the risk of device failure against the cost of reliable performance.

* Security: Securing the network is essential. SASE introduces comprehensive, end-to-end security. At this stage, it’s important to include securing Internet circuits when breaking out to the cloud and with a holistic approach, security itself can often be fuelled by savings made elsewhere.

With this as a starting point, similar considerations then need to be made across cloud and security to ensure a robust business case and strategy.

Why plan your route with a roadmap?

A roadmap is an essential tool to address this multifaceted challenge and highlight the link between investments and delivery capability. It illustrates to CxOs how SD-WAN delivers capability that can be leveraged and built upon by the next investment, while SASE brings to life the importance of developing an infrastructure business case that converges technology, investment, and decision-making to transform the business.

For SD-WAN and SASE a roadmap ultimately illustrates that the whole is greater than the sum of its parts.