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There’s no free lunch in SD-WAN, says Tata Communications

Software-defined wide-area networks may help to lower connectivity costs and prioritise network traffic, but enterprises must still invest in bandwidth to reap the benefits of the technology

Even as more enterprises in the Asia-Pacific (APAC) region turn to software-defined wide-area networks (SD-WAN) to address networking challenges, the technology will not deliver the goods if the underlying bandwidth is insufficient.

That is according to Song Toh, vice-president for global network services at Tata Communications, who noted that enterprises will still need to invest in enough high quality bandwidth to support their growing use of cloud services.

“If you have a network that’s not performing and you’re not connected 60% of the time, putting SD-WAN on top of it is not going to help you,” Toh said. “Where it helps is to provide a control layer that manages traffic based on your needs and connection quality, but there’s no free lunch – you better have enough bandwidth to take that on.”

Toh also warned enterprises against merely replacing old networking gear with new ones when migrating to SD-WAN. “You need to separate the new sites from old sites using some kind of gateway architecture, so that the whole network will not go down due to any misconfiguration,” he added.

Finally, enterprises should set appropriate policies in SD-WAN implementations to optimise traffic based on quality-of-service (QoS) requirements to avoid ending up with a congested network.

“If everything is class one, then your network is going to be congested. While employee satisfaction counts, at some point you’ll need to drop or throttle Netflix traffic on your corporate network,” Toh added.

According to technology analyst firm IDC, worldwide SD-WAN infrastructure and services revenues will grow at a compound annual growth rate (CAGR) of 69.6%, reaching $8.05bn in 2021.

In Southeast Asia, almost 56% of organisations have already deployed or are planning to deploy SD-WAN in their networks. Out of these, nearly 30% singled out the policy-based control and WAN optimisation capabilities of SD-WAN as top drivers for implementing the technology, according to IDC.

Nikhil Batra, IDC Asia-Pacific’s senior research manager for telecoms, said most WAN traffic today – to and from branch and remote sites – is destined for the cloud, either to cloud-based or hosted applications.

“The traditional WAN was architected for branch-to-datacentre traffic flows, not to efficiently support new cloud-driven traffic patterns,” he said, noting that enterprises that are still using traditional networks will face performance challenges and operational issues.

For example, besides the need to support diverse requirements and applications from different business units, traditional network architectures are too rigid to support the agility that organisations are looking for in expanding into new markets.

The growing prevalence of shadow IT and remote access to applications outside the safe realms of the traditional WAN have also introduced more network complexity, making traditional WAN inherently less secure, Batra said.

“SD-WAN are all about WAN transformation for the cloud era, helping to ensure branch offices and remote sites are configured consistently to connect users to applications, while assuring security, optimising network and application performance, and reducing complexity and costs in the process.”

Toh said in many cases, enterprises can lower the cost of network connectivity by using a combination of multiprotocol label switching (MPLS) links and Tata Communications’ IZO Internet WAN that is touted to deliver consistent network performance with service-level agreement (SLA) guarantees.

“If you have a 10Mbps MLPS link, it’s going to be very expensive if you want to increase the bandwidth to 50Mbps,” Toh said. “But if you have a MPLS link and add 40Mbps using IZO Internet WAN with SD-WAN on top to control the quality of your traffic, it’s going to be cheaper.”

While other service providers also offer internet WAN services, Toh claimed that some of them use the public internet to route traffic, which works on a good day but not at other times when traffic could be routed through several locations around the world.

As a challenger in the market, Toh said Tata Communications’ MPLS revenue is not as big as that of global rivals such as BT and AT&T. “From my perspective, we have to manage the transition into the future that is moving towards software-defined networks, rather than hold on to the past,” he said.

“This transition is a lot more painful for a large traditional telco that may have billions of dollars of MPLS revenue, while we are more flexible in helping enterprises replace 80% or 100% of their MPLS links based on their quality requirements and needs.”

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