- 14 September 2016 09:41
What CIOs need to know about SD-WANs
Despite all the recent talk about software defined networking (SDN) and how SDx benefits virtual environments and data centres, a key area is often overlooked. This is the network abstraction layer (NAL) which can affect application performance and value across the wide area network (WAN).
Abstraction is an outcome of virtualisation being applied to compute in creating an abstraction layer for multiple virtual machines operating within a single server. Similarly SD-WAN creates virtual or abstraction layers for bonding multiple connectivity types into encrypted tunnels that can be aligned to business intent policy.
In connecting users to applications and moving data more effectively over long distances, the WAN is complex. It encompasses connectivity for collaboration among enterprise users, clients, suppliers and partners, as well as the movement of data over distance for disaster recovery and business continuity.
While these requirements still exist, the adoption of virtualisation and the cloud across traditional WAN architectures, such as MPLS, has introduced performance bottlenecks that impair user productivity when connecting to data centre and cloud applications from branch and remote office locations. As cloud initiatives gain momentum and traction, CIOs are increasingly re-evaluating their corporate WAN requirements.
The rise of SD-WAN
This expanding use of cloud applications and service across the enterprise presents CIOs with the need to align IT resources to business mandates, to enable the organisation to operate at 'cloud speed'.
Gartner predicted that by 2018, Software-as-a-Service (SaaS) will become the dominant model for consuming application functionality for about 80 per cent of all organisations. This speed presents organisations with a number of challenges, including improving the responsiveness and agility of the business and the network while reducing costs and providing better performance for cloud applications. The need for increased responsiveness and agility in the enterprise is particularly critical when it comes to the opening of a new office or branch location. For example, if IT resources need to be moved, the process to add, move or change MPLS connectivity can often take swathes of time and disrupt the business.
Establishing connectivity at a new site, or increasing the bandwidth to an existing one, can take up to a month or longer to implement. While lower-cost internet connectivity has been available, it has lacked the scale, reliability and security required to support business-enabling applications. And if internet connectivity was purchased, it often sits idle until needed in back-up or fail-over situations.
First step for CIOs
CIOs are now actively evaluating software-defined WAN (SD-WAN) solutions as a potential way to better align WAN resources with business mandates. IDC predicts that the SD-WAN market will grow to become a $US6 billion industry by 2020.
Yet not all SD-WANs are the same. Some deliver only on the more basic of requirements of broadband connectivity, path selection, zero-touch provisioning, centralised management and cost reductions. It’s important that CIOs think more holistically about the WAN. While SD-WAN is central to building a better WAN, it is critically important that organisations ensure they are addressing key aspects such as performance, visibility and control, security and extensibility to realise the full potential that an SD-WAN can deliver.
When implemented correctly, an SD-WAN can help distributed enterprises to connect users flexibly and securely to applications by utilising any combination of underlying transport technologies without compromising application performance. Performance is arguably the most critical pillar of building a better WAN. It’s not just about adding bandwidth; it’s about enabling the use of multiple forms of transport and fixing any issues those links might have, such as packet loss, latency and jitter, so that the connections perform like a private line. This is especially important for cloud users and those who are increasingly accessing SaaS applications in branch and remote office locations. SD-WANs support multiple paths and allows connectivity decisions to be made independent of carriers, which helps enterprises to avoid lengthy procurement and deployment delays for a faster time to service at the branch.
Once connected, an SD-WAN fabric also provides visibility into both data centre and cloud applications, along with the ability to centrally assign business intent policies to secure and control all WAN traffic. It will determine the best path, whether MPLS, broadband or a combination of both, for each application based on customer-defined policies and real-time network quality measurements, all while keeping in-flight data encrypted edge-to-edge.
Keeping WAN connections secure from threats when data and applications are in transit is key. Through virtual overlays, additional levels of security can be offered through micro-segmentation, the ability to segment application overlays by user and access level. Finally, SD-WANs need to be scalable and non-disruptively interoperate with an organisation’s existing infrastructure.
Since a broadband WAN is not an all-or-nothing approach, CIOs can move at their own pace when it comes to deploying an SD-WAN solution. While the ultimate goal may be a 100 per cent broadband WAN, CIOs can take incremental steps by first deploying a hybrid WAN.
As MPLS upgrades arise, businesses can evaluate lower-cost broadband internet services as an alternative for connecting users to applications. This provides an opportunity to decrease their reliance on MPLS bandwidth and use only that connectivity for the remaining data centre applications. CIOs can then confidently embrace the internet and accelerate cloud initiatives and tightly align WAN resources to business requirements.
Ultimately, enterprises will become increasingly drawn to SD-WAN models as virtualisation and cloud applications become standard practice, further magnifying the inadequacies of legacy WAN architectures. Transitioning to a holistic SD-WAN model can be accomplished with minimal disruption and cost, as internet services can be introduced into the WAN without compromising application performance or the existing MPLS network. Given that SD-WAN adoption is predicted to rise at an astronomical rate and will soon become the norm, now is the best time for CIOs to move their company towards a hybrid or broadband WAN.