To some, Software-Defined Wide Area Networks (SD-WANs) are a revolution, providing the ability to identify the nature of data flows, prioritise them and deliver homogeneity of performance. This permits IT departments to deploy them “seamlessly between the decentralisation and globalisation of its enterprise footprint and its desire to have traffic managed through a central monitoring setup”, says Todd Kiehn, VP of Product Management GTT. He states this in his IT Pro Portal article, ‘The impact of SD-WAN adoption on digital transformation and corporate strategy’.
One management interface
SD-WANs can also be orchestrated through one management interface - perhaps similarly to legacy Wide Area Networks (WANs), which were easy to administer and orchestrate. He adds: “The SD-WAN layer, while providing agility, efficiency and better performance, also brings some complexity, requiring new skills for the teams responsible for operating the network”. However, he comments that the security of data streams and the direct access to services in the cloud from remote sites often require a change in network architecture, mesh and route selection.
Based on this, he wisely advises organisations that they need to think seriously about security from the outset of the decision to adopt SD-WANs, which must also be “integrated into deployments, cloud access, virtual instances, container services and beyond.” Network virtualisation has made network monitoring increasingly hard. He says it requires IT teams to go beyond equipment and connections, and they need to study applications and network topologies in different layers. He comments: “This is where global network operators have an advantage over their non-operator competitors, as they can easily provide end-to-end monitoring from their supervisory portal.”
He adds: “This change is driving IT teams to abandon a do-it-yourself approach and to rely instead on outsourcing SD-WAN services. According to Frost & Sullivan, 80 per cent of enterprises are choosing managed SD-WAN services, compared to 20 per cent doing it themselves.” The thing is, there are several SD-WAN providers responding to the same problem, but with different approaches. These include Pure SD-WAN players, Network Operators, Integrators and those developing in-house solutions. The choice of approach very much depends on the expertise of the in-house IT teams.
They will no doubt be aware of the proposed benefits of SD-WANs, and these go beyond cost-efficiencies. Even Kiehn claims that they enable a combination of different access types at site, delivering more uptime and bandwidth for less money than MPLS can. However, therein lies a weakness because SD-WANs are great, but they aren’t a revolution. Creating or adding more bandwidth doesn’t necessarily reduce or mitigate latency and packet loss – the gremlins that are the culprits associated with slowing down WANs, and their impact increases with distance.
Do the claims stack up?
So, yes, organisations may deploy SD-WANs for accelerating digital transformation, to manage the explosion of application traffic to the cloud – as well as the need for “homogeneous network performance at all sites”, but there is still the question about whether all of the claims stack up. Arguably, SD-WANs need a WAN Data Acceleration overlay for digital transformation and the Internet of Things. With increases of cloud application traffic comes ever-increasing data volumes, and SD-WANs on their own can’t mitigate the impact of latency and packet loss as much as their vendors often promise.
However, SD-WANs like so many other software-defined technologies, provide a great number of benefits to the operations team with its easy-to-use and deployment features, as well as decreasing costs. However, they are not a panacea for resolving all the WAN ills, despite what the soothsayers preach. Can it on its own help with a digital transformation process? If that process involves including bringing onboard more of the remote and outlying branches of the organisation, then it can make a significant different in connecting these offices in a cost-efficient way that in the past would have inhibited organisation-wide digitalisation.
Data volumes increasing
As data volumes move across the WAN, new data formats are used, and data flows increase from any digitalisation project. The ability to aggregate data over multiple low-cost broadband connections to outlying branches or small offices makes a huge difference. However, there are a couple of situations where, no matter how much WAN capacity you have, the performance is less than expected.
Many of the data formats that are now traversing over WANs don’t lend themselves to the traditional methods of compression and deduplication to sufficiently improve WAN performance. Therefore, to make the best of the functionality that one can get from implementing an SD-WAN, there is a need to adopt a different means of accelerating the data across SD-WAN infrastructure – whether this is for digital transformation or another type of implementation.
WAN Acceleration solutions, such as Bridgeworks PORTrockIT, offer the ability to mitigate the effects of latency and packet loss. For example, Investec Wealth & Investment required access to servers located in the UK, so it can provide clients with offshore investment capability. The Bank is partnered with Swiss Bank, and it uses its Swiss brokering licence.
The issue is that geographic latency between South Africa and the UK meant less than 20 per cent utilisation of WAN links were used for the replication of RRP data. MPLS latency between the two counties is +-180ms. The time for these data sets to be moved across South Africa and the UK link is currently between 14-15 hours, which can cause challenges in keeping RRP databases in synchronicity. So, after completing a proof of concept (POC), Strat IT introduced Investec to Bridgeworks.
With no WAN acceleration, the base for the POC began with no acceleration, and with host-to-host traffic with accelerator in-path. The total traffic transferred between 1st February and 1st April 2018 was 9.3TB. The average rate of transfer was 3-5MB/s, and all of the databases were out of sync. Yet with WAN acceleration, the next step of the POC, the total traffic transferred between 1st February and 1st April 2019 equalled 55TB. This amounted to a 424 per cent increase in total traffic, with an average rate of transfer 11-15MB/s. Unlike when there was no WAN acceleration, all the Oracle and SQL databases were in sync.
This works because PORTrockIT takes the data stream and spreads it across a number of logical connections. This has the effect of mitigating the effects of latency – something that the SD-WAN providers fail to highlight, as SD-WANs do not reduce latency. Bridgeworks uses AI to manage this functionality, which has the benefit of mitigating packet loss, too. So, with a WAN Acceleration overlay, SD-WANs find a perfect partner that can achieve higher levels of bandwidth utilisation.
When you bring these together you get the best from both worlds: The flexibility of SD-WAN configuration, the ability to use low-cost connections and enterprise-wide management, and greater WAN performance. This can vastly improve the ability to implement digital transformation, back-up and restore data from multiple clouds or disaster recovery sites, and it can help to create a nimbler corporate strategy – one that could set even your own organisations apart from its competitors.
David Trossell, CEO and CTO, Bridgeworks