An increasing number of businesses are switching to a Software-Defined Wide Area Network (SD-WAN), which is a unique approach to wide-area networking because it combines traditional WAN technologies with the Internet and provides more visibility within an organisation.
The move to SD-WAN is largely driven by distributed enterprises with multiple remote offices, which are increasingly using business-critical, cloud-based applications and tools that are migrating away from performance-inhibited wide-area networks (WAN).
According to Louis Kirstein, DSM Expert for Connectivity Services at T-Systems South Africa, the visibility provided by an SD-WAN enables network administrators to oversee the network and monitor traffic for inconsistencies. From a security perspective, this functionality allows network administrators to ensure applications are performing accordingly and make sure security elements are running correctly.
“SD-WAN is an element of the bigger security framework of an organisation. If there’s one way to summarise how an SD-WAN fits into the overall security landscape of an organisation, it is to say that it enables centralised policy management and distributed policy enforcement,” Kirstein says.
Thus, one of the main advantages of SD-WAN is that it is software-defined and not hardcoded in infrastructure, so policies can be distributed from a central console to all sites and branches and these can be executed by various components.
Considering security
What makes SD-WAN technology so popular is that it allows businesses to make their networks more efficient and dynamic when it comes to consuming network resources, increasing bandwidth at a lower cost, as well as providing more options for connection types and vendor selection when building their networks.
At the same time, says Kirstein, organisations must give due consideration to securing their SD-WAN, as SD-WAN solutions do not provide in-built security, which is critical for direct Internet access. Yet, the need for an organisation to protect its IT environment from a hostile, public Internet, which is the carrier of its Internet traffic, is fundamental.
“SD-WAN platforms are inherently not secure. It’s the security technology within a secure SD-WAN solution that makes it safe. Secure SD-WAN allows each branch location to benefit from diverse security policies and connectivity, while IT enables corporate and Internet traffic simultaneously – on the same circuits,” says Kirstein.
For organisations that are looking to address the security aspects of their SD-WAN deployments, certain vendors can deliver proprietary secure SD-WAN solutions that use the network’s firewall technology to perform routing, says Lukas van der Merwe, Specialist Sales Executive for Security at T-Systems South Africa.
No need for bolt-on layer
“There is no need for a bolt-on security layer to provide a holistic end-to-end security solution, in terms of network access. Secure SD-WAN has an architecture that includes a secure perimeter protection capability, as well as components that are needed to access cloud-based solutions.”
Van der Merwe notes that what is essentially different in a secure SD-WAN solution is that it has a distributed firewall topography, managed from a single point.
“A secure SD-WAN solution uses the firewall platform, which is distributed across the entire enterprise environment, towards each endpoint, the perimeter is broadened towards the branch offices and it is all managed centrally.”
SD-WAN functions need to be virtualised to keep up with evolving security threats and to control the cost of updating and upgrading security elements. Van der Merwe says that virtualising the functions, or the ability to define policies and deploy them centrally and in real-time provides more control and visibility, which – in the context of a secure SD-WAN solution – does improve security.
Ultimately, the benefits of a secure SD-WAN solution are undeniably extensive, and enable enterprises to not only meet compliance mandates, reduce infrastructure and circuit costs, but also to improve and simplify segmentation and decrease branch sprawl.
